JP3118849B2 - Focus detection device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a focus detecting device having a plurality of focus detecting areas.

[0002]

2. Description of the Related Art Conventionally, a photographing screen has a plurality of focus detection areas, and a focus adjustment state of a photographing optical system is determined based on output signals of a plurality of pairs of light receiving sections corresponding to the respective focus detection areas. Known focus detection devices are known (for example,
See JP-A-2-50115).

FIGS. 32 (a) and 32 (b) show the arrangement of focus detection areas of this type of focus detection device. First, in FIG. 32A, two band-shaped focus detection areas (hereinafter, referred to as “focus detection areas”) in the shooting screen P
Three cross-shaped focus detection areas (hereinafter, simply referred to as cross-shaped focus detection areas) in which the focus detection areas are simply set to be orthogonal to each other are arranged in a straight line in the long side direction of the shooting screen P, The cross-shaped focus detection area at the center of the screen is set at the center of the shooting screen P. Further, one focus detection area included in each cross-shaped focus detection area is set in parallel with the long side direction of the shooting screen P, and therefore, the other focus detection area is inevitably in the short side direction of the shooting screen P. They are arranged in parallel. Next, in FIG. 32B, three cross-shaped focus detection areas are arranged in a straight line in the diagonal direction of the screen within the shooting screen P, and the cross-shaped focus detection area at the center of the screen is set at the center of the shooting screen P. ing. Further, one focus detection area included in each cross-shaped focus detection area is set parallel to the long side direction of the screen, and therefore, the other focus detection area is necessarily parallel to the short side direction of the photographing screen P. Be placed.

[0004]

However, the above-mentioned conventional focus detection apparatus has the following problems. (1) In the cross-shaped focus detection area set at a place other than the center of the shooting screen, the length of each focus detection area is set in consideration of the asymmetricity of the focus detection optical system with respect to the optical axis of the shooting optical system. Therefore, the focus detection accuracy deteriorates depending on the subject. The details will be described later.

(2) In a focus detection optical system in which a focus detection area is set at the center of the screen and at a place other than the center, since a condenser lens and a separator lens are integrally formed, the vicinity of the optical axis of the focus detection optical system and the optical axis The degree of freedom in the design of the optical system is limited with respect to the outside location. Usually, the focus detection accuracy at the center of the screen is prioritized, so that the performance of the focus detection optical system outside the optical axis is inferior to the performance near the optical axis. Further, since the focus detection optical system is asymmetric with respect to a plane including the optical axis of the photographing optical system, a pair of secondary subject images re-imaged by the focus detection optical system is also asymmetric. In the conventional focus detection device, since the pixel pitch, the pixel width, the pixel tilt direction, and the tilt angle of the light receiving unit of the photoelectric conversion sensor are not set in consideration of the above, the focus detection area other than the center of the screen is not set. Focus detection accuracy is reduced.

Hereinafter, the above items (1) and (2) will be described in detail. FIG. 36 shows an example of setting three focus detection areas.
FIG. 37 shows a focus detection optical system in which the three focus detection areas shown in FIG. 36 are set. First, in FIG.
H, ALH and ARH are band-shaped focus detection areas,
1 at the center of the shooting screen P and at a place other than the center
Set on a straight line.

Next, in FIG. 37, MSK is a field mask installed near a predetermined imaging plane of the photographing optical system, and each focus detection area ACH, ALH, ARH is formed. F
R, FC, and FL are condenser lenses, which correspond to the focus detection areas ARH, ACH, and ALH, respectively. SR
H1, SRH2, SCH1, SCH2, SLH1, SL
H2 is a separator lens, and a separator lens S
RH1, SRH2, SCH1, SCH2, SLH1, S
LH2 makes a pair, and focus detection areas ARH, A
CH and ALH respectively. Further, SNS is a sensor that performs photoelectric conversion, EH1 and EH2 are pupil regions of an imaging optical system (not shown), and AX is an optical axis of the imaging optical system.

[0008] The primary images of the subject formed in the focus detection areas ARH, ACH and ALH after passing through the pupil area EH1 of the photographing optical system pass through the condenser lenses FR, FC and FL and the separator lenses SRH1, SCH1 and SLH1. Thus, the image is re-imaged as three secondary object images on the sensor SNS. In addition, the primary images of the subject formed in the focus detection areas ARH, ACH, and ALH after passing through the pupil region EH2 of the imaging optical system pass through the condenser lenses FR, FC, FL, and the separator lenses SRH2, SCH2, and SLH2. , 3 corresponding to each focus detection area on the sensor SNS
It is re-imaged as two secondary subject images.

In the pair of secondary object images re-imaged on the sensor SNS, their image shift amounts are detected, and the focus adjustment state of the photographing optical system is detected. However, the pair of secondary object images re-imaged by the focus detection optical system includes an image shift amount caused by the imaging optical system being out of focus and an optical axis of the imaging optical system. There is an image shift amount caused by being arranged asymmetrically with respect to AX. That is,
The focus detection area set farther from the center of the screen through which the optical axis AX of the imaging optical system passes has a greater influence of the focus detection optical system arranged asymmetrically with respect to the optical axis AX.

FIG. 38 shows a case where the primary image of the subject formed in the focus detection area ACH at the center of the screen shown in FIG.
(A) shows the image height and distortion when refocused as a pair of secondary object images on the sensor SNS by the focus detection optical system shown in (a). (B) shows the image height and distortion of the secondary subject image re-formed by the separator lens SCH2, and (c) shows the pair of images shown in (a) and (b). Shows the difference in distortion. FIG. 39 shows focus detection areas ALH and ARH at locations other than the center of the screen shown in FIG.
37 shows the image height and distortion when the primary image of the subject formed on the sensor SNS is re-formed as a pair of secondary subject images on the sensor SNS by the focus detection optical system shown in FIG.
(A) shows the image height and distortion of the secondary subject image re-formed by the separator lens SLH1 or SRH1, and (b) shows the image of the secondary subject image re-formed by the separator lens SLH2 or SRH2. (C) shows the difference between the pair of distortions shown in (a) and (b).

The difference in distortion, which is problematic when detecting the image shift amount of the secondary subject image for focus detection, is based on the difference in distortion in the focus detection area ACH set at the center of the screen shown in FIG. Also, the difference between the distortions of the focus detection areas ALH and ARH set at locations other than the center of the screen shown in FIG.
In order to obtain the same focus detection accuracy as the center of the screen at a position other than the center of the screen, as shown in FIG. 39C, the length of the focus detection areas ALH and ARH at a position other than the center is adjusted by the center focus detection. The length WR needs to be shorter than the length WC of the area ACH.

In the focus detection area other than the center of the screen, as shown in FIG. 40, if the focus detection areas ALV and ARV are set in the tangential direction of a concentric circle with the center of the screen,
A pair of focus detection areas ACH 2 set at the center of the screen
Although worse than the difference between the distortions of the next subject image, FIG.
The asymmetry of the focus detection optical system is improved from the focus detection areas ALH and ARH set in the radiation direction from the center of the screen shown in FIG. 6, and the distortion is smaller than the difference between the distortions of the focus detection areas ALH and ARH. Therefore, the length of the focus detection areas ALV, ARV is equal to the length of the focus detection areas ALH, ARH.
H can be set longer than H, and a wide range of focus detection can be performed.

FIG. 41 shows a focus detection optical system in which a cross-shaped focus detection area is set at the center of the photographing screen P and at a place other than the center. Note that the same components as those of the focus detection optical system shown in FIG. 37 are denoted by the same reference numerals, and differences will be mainly described. Further, since the focus detection area set on the right side of the screen is an object with respect to the optical axis AX of the photographing optical system, the focus detection areas ALH and ALV set on the left side of the screen will be mainly described. In the figure, FL is a condenser lens, RX is an aperture mask, and RLH1, RLH2, RLV1, and RLV2 are apertures of the aperture mask RX. Aperture mask opening RLH
1 and RLH2, RLV1 and RLV2 form a pair, and correspond to the focus detection areas ALH and ALV, respectively. SLH
Reference numerals 1, SLH2, SLV1, and SLV2 denote separator lenses, SLH1 and SLH2, SLV1, and SLV2 form a pair, and aperture mask openings RLH1, RLH2, and RLV.
1 and RLV2 respectively. Further, PCH1,
PCH2, PCV1 and PCV2 are light receiving units set on the sensor SNS, and correspond to the focus detection areas ALH and ALV, respectively.

The primary image of the subject formed in the focus detection area ALH after passing through the pupil areas EH1 and EH2 of the photographing optical system is formed by a condenser lens FL and an aperture mask opening RLH.
1, RLH2 and separator lenses SLH1, SLH
2, the light receiving sections PLH1 and PLH2 of the sensor SNS
Is re-imaged as a secondary object image. The focus detection area AL passes through the pupil areas EV1 and EV2 of the photographing optical system.
The primary image of the subject formed on the sensor V is supplied to the sensor SN via the condenser lens FL, the aperture mask openings RLV1, RLV2, and the separator lenses SLV1, SLV2.
It is re-imaged as a secondary object image on the S light receiving units PLV1 and PLV2. That is, a focus detection area ALH set in a direction other than the center of the screen in a radial direction from the center of the screen.
Are detected in the exit pupil regions EH1, EH of the photographing optical system.
2 are used. On the other hand, the exit pupil areas EV1 and EV2 of the photographing optical system are used for focus detection of a focus detection area ALV set in a tangential direction of a circle concentric with the center of the screen at a place other than the center of the screen. A passing light beam is used. In addition,
The light flux reaching a point other than the center of the screen is limited not only by the aperture of the photographing optical system but also by the outer diameter of the hood and lens.

FIG. 42 shows a substantial pupil aperture shape EX when the lens side is viewed from the focus detection areas ALH and ALV set at places other than the center of the screen. As shown in the figure,
The aperture is not circular except in the center of the screen, and the exit pupil areas EH1, EH2, EV1, EV2 are set therein. The pupil areas EV1 and EV2 corresponding to the focus detection area ALV set in a tangential direction of a circle concentric with the center of the screen at a place other than the center of the screen are symmetrical areas with respect to the pupil aperture shape EX, and have passed through this area. The light beams have substantially the same aberration characteristics. Therefore, a pair of secondary subject images formed by these light beams have symmetry and are suitable for focus detection. On the other hand, the pupil regions EH1 and EH2 corresponding to the focus detection area ALH set in the radial direction from the center of the screen at a place other than the center of the screen are regions asymmetric with respect to the pupil aperture shape EX, and pass through these regions. The resulting light flux has different aberration characteristics. As a result, the secondary subject image formed by these light beams loses symmetry, and when the focus detection is performed using the secondary subject image at a portion distant from the center of the focus detection area ALH, the focus detection is performed as described above. The error increases.

As described above, when the focus detection area is set at a place other than the center of the photographing screen, the length of the focus detection area is set shorter than the length of the focus detection area set at the center of the screen. The focus detection area set in the radial direction from the center should be shorter than the focus detection area set in the tangential direction of the screen center and the concentric circle to perform focus detection, and the focus detection error should be minimized. Must.

An object of the present invention is to provide a focus detection device capable of performing accurate focus detection in a focus detection area set at a place other than the center of a photographing screen.

[0018]

Means for Solving the Problems The inventions of claims 1 to 3 will be described with reference to FIG. 9 showing an embodiment. The invention of claim 1 is directed to a plurality of focal points set in a photographing screen. A focus detection optical system that guides a light beam that has passed through the detection area onto the photoelectric conversion unit, and a light beam that has a plurality of pairs of light-receiving units made up of a plurality of pixels corresponding to each focus detection area, and has passed each focus detection area The present invention is applied to a focus detection device including: a photoelectric conversion unit that receives light; and a focus detection calculation unit that detects a focus adjustment state of an imaging optical system for each focus detection area based on an output signal of the photoelectric conversion unit. . Then, the plurality of focus detection areas are set at the center of the shooting screen and at a place other than the center,
The pixel pitch and / or pixel width of the pair of light receiving units PCH1 and PCH2 and PCV1 and PCV2 corresponding to the focus detection area set at the center of the shooting screen, and the focus detection area set at a place other than the center of the shooting screen The above object is achieved by setting the pixel pitch and / or pixel width of the corresponding pair of light receiving units PLH1 and PLH2 and PLV1 and PLV2 to be relatively different. According to the second aspect of the present invention, a pair of light receiving sections PLH1 and PLH1 corresponding to a focus detection area set at a place other than the center of the photographing screen.
H2, pixel pitches KRLH1 and K of PLV1 and PLV2
RLH2 and KRLV are a pair of light receiving units PCH1 and PCH1 corresponding to a focus detection area set at the center of the shooting screen.
2. Pixel pitches KCH and KCV of PCV1 and PCV2 are set finer. Further, according to the third aspect of the present invention, a pair of light receiving portions PLH1 and PLH2, PLV1 and PL corresponding to a focus detection area set at a place other than the center of the photographing screen.
The pixel width HRLH1, HRLH2, and HRLV of V2 are set wider than the pixel widths HCH and HCV of the pair of light receiving units PCH1, PCH2, PCV1, and PCV2 corresponding to the focus detection area set at the center of the shooting screen.

FIG. 7 shows an embodiment of the present invention.
According to the fourth aspect of the present invention, a light beam passing through a cross-shaped focus detection area in which two band-shaped focus detection areas are set to be orthogonal to each other in a photographing screen P is transmitted to a focus detection optical system. The present invention is applied to a focus detection device including: a photoelectric conversion unit that receives light through the photoelectric conversion unit; and a focus detection calculation unit that detects a focus adjustment state of the imaging optical system for each band-shaped focus detection region based on an output signal of the photoelectric conversion unit. Is done. The cross-shaped focus detection areas ARH and ALV, and the ALH and ALV are set at locations other than the center of the shooting screen P, and one of the cross-shaped focus detection areas ARH and ALH of the cross-shaped focus detection area is set at the center of the shooting screen P. And the zonal focus detection areas ARH and ALH set on this radiation.
Is the length WRLH of the zonal focus detection areas ARH and ALH.
Length WR of the band-like focus detection areas ARV and ALV orthogonal to
The above object is achieved by setting the length to be shorter than the LV.

FIG. 9 shows one embodiment of the present invention.
According to a seventh aspect of the present invention, a light beam passing through a cross-shaped focus detection area in which two band-shaped focus detection areas are set to be orthogonal to each other in a photographing screen is photoelectrically converted. A focus detection optical system leading to the means, and a plurality of pairs of light receiving sections each including a plurality of pixels corresponding to each band-shaped focus detection area, and photoelectric conversion means for receiving a light beam passing through each band-shaped focus detection area. The present invention is applied to a focus detection device including a focus detection calculation unit that detects a focus adjustment state of the imaging optical system for each band-shaped focus detection area based on an output signal of the photoelectric conversion unit. The cruciform focus detection area is set at a location other than the center of the imaging screen, and one of the zonal focus detection areas of the cruciform focus detection area is set on radiation from the center of the imaging screen, and A pair of light receiving sections PLH1, PLH1 corresponding to the band-shaped focus detection area set above
The pixel pitch and / or pixel width of PLH2 is relatively different from the pixel pitch and / or pixel width of a pair of light receiving units PLV1 and PLV2 corresponding to the band-shaped focus detection areas perpendicular to the band-shaped focus detection areas PLH1 and PLH2. By setting as described above, the above object is achieved. According to the invention of claim 6, the light receiving unit PLH corresponding to the band-shaped focus detection area set on the radiation from the center of the imaging screen.
1, PLH2 pixel pitches KRLH1 and KRLH2 are:
Pixel pitch KRLV of the light receiving units PLV1 and PLV2 corresponding to the band-shaped focus detection area orthogonal to the band-shaped focus detection area
It is set more finely than. Furthermore, in the invention of claim 7,
Pixel width H of the light receiving units PLH1 and PLH2 corresponding to the band-shaped focus detection area set on the radiation from the center of the imaging screen
RLH1 and HRLH2 are light receiving sections PLV1 and PL corresponding to a band-shaped focus detection area orthogonal to the band-shaped focus detection area.
It is set wider than the pixel width HRLV of V2.

FIG. 9 shows an embodiment according to the present invention.
According to the invention of claim 8, the invention of claim 8 comprises a focus detection optical system that guides a light beam that has passed through a focus detection area set in a photographing screen onto a photoelectric conversion unit, and a pair of light receiving units including a plurality of pixels. Focus detection comprising: photoelectric conversion means for receiving a light beam having passed through the focus detection area; and focus detection calculation means for detecting a focus adjustment state of the photographing optical system in the focus detection area based on an output signal of the photoelectric conversion means. Applies to equipment. The focus detection area is set on radiation from the center of the imaging screen, and one of the light receiving sections PLH1 and PLH2 of the pair of light receiving sections PLH1 and PLH2 corresponding to the focus detection area.
Pixel pitch KRLH1 and / or pixel width HRLH
1 is set to be relatively different from the pixel pitch KRLH2 and / or the pixel width HRLH2 of the other light receiving portion PLH2, thereby achieving the above object.

The invention according to claim 9 will be described with reference to FIG. 10 showing an embodiment. The invention according to claim 9 is to reconstruct a subject image of a focus detection area set in a photographing screen on a photoelectric conversion means. A focus detection optical system that forms an image of a secondary object by forming an image; a photoelectric conversion unit that receives a light beam that has passed through the focus detection area with a pair of light receiving units including a plurality of pixels; and an output signal of the photoelectric conversion unit. The present invention is applied to a focus detection device including a focus detection calculation unit that detects a focus adjustment state of an imaging optical system in a focus detection area based on the focus detection area. The focus detection area is set on the radiation from the center of the imaging screen at a location other than the center of the imaging screen, and the pixel pitch of each of the pair of light receiving units PLH1 and PLH2 corresponding to the focus detection area is determined by the focus detection area. The above object is achieved by setting so that the distortion of the secondary object image re-imaged by the optical system is corrected.

[0023] To explain the invention of claim 10 in association with FIG. 11 showing an embodiment, the invention of claim 10, photoelectric conversion of the light beam passing through the plurality of strip-like focus detection areas set in the photographing screen a focus detecting optical system for guiding on means, a pair of light receiving portions comprising a plurality of pixels having a plurality of pairs corresponding to the respective strip-like focus detection region, a photoelectric conversion means for receiving the light flux that has passed through the band-shaped focus detection area The present invention is applied to a focus detection device including a focus detection calculation unit that detects a focus adjustment state of the imaging optical system for each band-shaped focus detection area based on an output signal of the photoelectric conversion unit. And a plurality of band-shaped focus detection areas
It is set in the central and non-central location of the shooting screen, each
The pixels of each light receiving section corresponding to the band-shaped focus detection area are
Are inclined with respect to the direction perpendicular to the longitudinal direction of
Ri, a pair of light receiving portions PCH1 corresponding to strip the focus detection area set in the center of the shooting screen and PCH2, PCVl and P
Tilt-out direction LCH pixel of CV2, and LCV, a pair of light receiving portions PLH1 corresponding to strip the focus detection area set in a location other than the center of the shooting screen and PLH2, PLV1 and PLV
The above object is achieved by setting the inclination directions LRLH and LRLV of the two pixels to be relatively different from each other.

[0024]

According to the first aspect, the plurality of focus detection areas are set at the center of the shooting screen and at a place other than the center,
The pixel pitch and / or pixel width of the pair of light receiving units PCH1 and PCH2 and PCV1 and PCV2 corresponding to the focus detection area set at the center of the shooting screen, and the focus detection area set at a place other than the center of the shooting screen The pixel pitches and / or pixel widths of the corresponding pair of light receiving sections PLH1 and PLH2 and PLV1 and PLV2 are set to be relatively different, and the light flux passing through the plurality of focus detection areas is passed through the focus detection optical system. Based on the output signal of the photoelectric conversion means for receiving and receiving light, the focus detection calculation means detects the focus adjustment state of the photographing optical system for each focus detection area. Claim 2
Here, a pair of light receiving units PLH1, PLH2, PLH corresponding to a focus detection area set at a place other than the center of the photographing screen
Pixel pitches KRLH1 and KRLH2 of V1 and PLV2
KRLV is a pair of light receiving sections PCH1, PCH2, PCV1 corresponding to a focus detection area set at the center of the photographing screen.
And the pixel pitches KCH and KCV of the PCV2 are set finer, and each of the focus detection arithmetic means based on the output signal of the photoelectric conversion means for receiving the light flux passing through the plurality of focus detection areas via the focus detection optical system. The focus adjustment state of the imaging optical system is detected for each focus detection area. Claim 3
Here, a pair of light receiving units PLH1, PLH2, PLH corresponding to a focus detection area set at a place other than the center of the photographing screen
Pixel widths HRLH1, HRLH2, HR of V1 and PLV2
LV is a pair of light receiving sections PCH1 and PCH2, PCV1 and PCV corresponding to a focus detection area set at the center of the photographing screen.
Each focus is calculated by a focus detection calculation unit based on an output signal of a photoelectric conversion unit that receives a light beam that is set to be wider than the pixel widths HCH and HCV of CV2 and passes through the plurality of focus detection areas via a focus detection optical system. The focus adjustment state of the imaging optical system is detected for each detection area.

In the fourth aspect, the cross-shaped focus detection area ARH
, ALV, ALH, and ALV are set at locations other than the center of the imaging screen P, and one of the zonal focus detection areas ARH, ALH of the cross-shaped focus detection area is set on radiation from the center of the imaging screen P. At the same time, the length WRLH of the band-shaped focus detection areas ARH and ALH set on the radiation is set shorter than the length WRLV of the band-shaped focus detection areas ARV and ALV orthogonal to the band-shaped focus detection areas ARH and ALH. Cross-shaped focus detection area ARH and ARV, A
On the basis of an output signal of a photoelectric conversion unit that receives a light beam passing through the LH and the ALV through a focus detection optical system, the focus detection operation unit detects a focus adjustment state of the imaging optical system for each band-shaped focus detection area.

In the present invention, the cross-shaped focus detection area is set at a position other than the center of the photographing screen, and one of the cross-shaped focus detection areas is set on radiation from the center of the photographing screen. And a pair of light receiving sections PLH corresponding to the band-shaped focus detection area set on the radiation.
1 and a pair of light receiving portions PLV1 and PLV2 corresponding to the pixel pitch and / or pixel width of PLH2 and the band-shaped focus detection regions orthogonal to the band-shaped focus detection regions PLH1 and PLH2.
The pixel pitch and / or the pixel width are set to be relatively different from each other based on an output signal of a photoelectric conversion unit that receives a light beam passing through these cross-shaped focus detection areas via a focus detection optical system. Then, the focus adjustment state of the photographing optical system is detected for each band-shaped focus detection area by the focus detection calculation means. According to the sixth aspect, the light receiving unit PLH corresponding to the band-shaped focus detection area set on the radiation from the center of the imaging screen.
1, PLH2 pixel pitches KRLH1 and KRLH2 are:
Pixel pitch KRLV of the light receiving units PLV1 and PLV2 corresponding to the band-shaped focus detection area orthogonal to the band-shaped focus detection area
Based on the output signal of the photoelectric conversion means for receiving the light flux passing through these band-shaped focus detection areas through the focus detection optical system, the focus detection calculation means sets the imaging optics for each band-shaped focus detection area. Detect the focus state of the system. Further, in the seventh aspect, the light receiving unit PL corresponding to the band-shaped focus detection area set on the radiation from the center of the imaging screen.
The pixel widths HRLH1 and HRLH2 of H1 and PLH2 are set to be wider than the pixel widths HRLV of the light receiving units PLV1 and PLV2 corresponding to the band-shaped focus detection areas orthogonal to the band-shaped focus detection areas, and have passed through these band-shaped focus detection areas. On the basis of the output signal of the photoelectric conversion means for receiving the light beam via the focus detection optical system, the focus detection operation means detects the focus adjustment state of the photographing optical system for each band-shaped focus detection area.

In the eighth aspect, the focus detection area is set on the radiation from the center of the photographing screen, and one of the light receiving sections PLH1 and PLH2 of the pair of light receiving sections PLH1 and PLH2 corresponding to the focus detection area. The pixel pitch KRLH1 and / or the pixel width HRLH1 and the other light receiving unit PLH2
Pixel pitch KRLH2 and / or pixel width HRLH
2 are set to be relatively different from each other, and based on an output signal of a photoelectric conversion unit that receives a light beam that has passed through these focus detection regions via a focus detection optical system, the focus detection calculation unit performs The focus adjustment state of the photographing optical system is detected.

According to the ninth aspect, the focus detection area is set on the radiation from the center of the imaging screen at a place other than the center of the imaging screen, and the focus detection areas of the pair of light receiving sections PLH1 and PLH2 corresponding to the focus detection area are set. Each pixel pitch is
The distortion of the secondary subject image re-formed by the focus detection optical system is set so as to be corrected, and the subject images in these focus detection areas are output to the output signals of the photoelectric conversion means for receiving light via the focus detection optical system. On the basis of this, the focus adjustment state of the photographing optical system in the focus detection area is detected by the focus detection calculation means.

In a tenth aspect, a plurality of band-shaped focus detection areas are provided.
Pixels of the light receiving portion but which together are set at the center and non-central location of the shadow window shooting, corresponding to the respective strip-like focus detection area
Are parallel to each other at an angle to the direction perpendicular to the longitudinal direction of each light receiving section.
And a pair of light receiving sections PCH1, PCH2, PCH2 corresponding to a band-shaped focus detection area set at the center of the photographing screen.
CV1 and PCV2 of the pixels of the tilt-out direction LCH, and the LCV,
A pair of light receiving units PLH1, PLH2 and PLV corresponding to a band-like focus detection area set at a place other than the center of the photographing screen
The tilt directions LRLH and LRLV of the pixels 1 and PLV2 are set so as to be relatively different from each other, and a photoelectric beam that receives light beams passing through the plurality of band-shaped focus detection areas via a focus detection optical system. Based on the output signal of the conversion means, the focus detection calculation means detects the focus adjustment state of the imaging optical system for each band-shaped focus detection area.

In the sections of the means for solving the above-mentioned problems and the operation, which explain the constitution of the present invention, the figures of the corresponding embodiments are used to facilitate understanding of the present invention. It is not limited to the embodiment.

[0031]

FIG. 1 shows the configuration of an optical system of a focus detection device according to the present invention. In the figure, AX is an optical axis of a photographing optical system (not shown), MSK is a field mask installed near a predetermined imaging plane equivalent to a film surface of the photographing optical system, ARX
1, ARX2, ACH, ACV, ALX1, ALX2
Denotes an opening of the field mask MSK, and corresponds to each focus detection area shown in FIG. Note that, in the following description, the reference numerals of the focus detection areas are assigned the reference numerals of the corresponding openings of the field mask MSK. Focus detection area ARX1, A
RX2, ACH, ACV, ALX1, and ALX2 are set so that the two focus detection areas are orthogonal to each other, and form a cross-shaped focus detection area. Focus detection area AC
H is set at the center of the screen along the long side direction of the shooting screen P, the focus detection area ACV is set at the center of the screen along the short side direction of the shooting screen P, and the focus detection area ARX
1, ARX2, ALX1, and ALX2 are set at positions other than the center of the screen at an angle of 45 degrees with respect to the focus detection areas ACH and ACV. These three cross-shaped focus detection areas are arranged in a straight line in the long side direction of the screen.
In order to maintain the focus detection accuracy as described above, FIG.
As shown in (a), the focus detection areas ARX1, ARX2, ALX1, AL set in places other than the center of the screen
The length LX of X2 is set shorter than the length LC of the focus detection areas ACH and ACV set at the center of the screen.

Reference numerals FR, FC, and FL denote condenser lenses, which are cross-shaped focus detection areas ARX1 and ARX, respectively.
2, corresponding to ACH and ACV, ALX1 and ALX2.
The optical axes of the condenser lenses FR and FL are decentered toward the optical axis AX from the centers of the cross-shaped focus detection areas ARX1 and ARX2 and ALX1 and ALX2, and pass through the cross-shaped focus detection areas ARX1 and ARX2 and ALX1 and ALX2. Deflecting the light beam to the optical axis AX side. The condenser lens F
R, FC, and FL each have a shape in which a round lens is shaved and a boundary surface is stuck, and are integrally formed of a transparent plastic material.

RX is an aperture mask, RRX11, RRX1
2, RRX21, RRX22, RCH1, RCH2, R
CV1, RCV2, RLX11, RLX12, RLX2
Reference numeral 1 denotes an aperture opening of the aperture mask RX. Aperture mask openings RRX11, RRX12, RRX
21 and RRX22, RCH1 and RCH2, RCV1 and R
CV2, RLX11 and RLX12, RLX21 and RLX
22 are paired with each other, and focus detection areas ARX1 and ARX1
RX2, ACH, ACV, ALX1, ALX2. A line connecting the centers of the aperture mask openings RRX11 and RRX12 is orthogonal to a line connecting the centers of the aperture mask openings RRX21 and RRX22.
A line connecting the centers of CH1 and RCH2 and a line connecting the centers of aperture mask openings RCV1 and RCV2 are orthogonal to each other and connecting the centers of aperture mask openings RLX11 and RLX12,
The line connecting the centers of the aperture mask openings RLX21 and RLX22 is orthogonal.

SRX11, SRX12, SRX21, S
RX22, SCH1, SCH2, SCV1, SCV2
SLX11, SLX12, SLX21, SLX22
Aperture mask openings RRX11, RRX12, R
RX21, RRX22, RCH1, RCH2, RCV
1, RCV2, RLX11, RLX12, RLX21,
A separator lens disposed behind the RLX22, the SRX11 and the SRX12, the SRX21 and the SRX2
2, SCH1 and SCH2, SCV1 and SCV2, SLX
11 and SLX12, and SLX21 and SLX22 form a pair. A line connecting the centers of the separator lenses SRX11 and SRX12 and the separator lenses SRX21 and SRX
Similarly, the line connecting the centers of the separator lenses SLX11 and SLX12 is orthogonal to the line connecting the centers of the separator lenses SCH1 and SCH2 and the line connecting the centers of the SCV1 and SCV2. , The line connecting the centers of the separator lenses SLX21 and SLX22 is orthogonal. Separator lenses SRX11, SRX12, SR
X21, SRX22, separator lenses SCH1, SC
H2, SCV1, SCV2, separator lens SLX1
1, SLX12, SLX21, and SLX22 form a separator lens group, respectively, and these three separator lens groups are integrally formed on a transparent plastic substrate.

SNS is a sensor that performs photoelectric conversion, PR
X11, PRX12, PRX21, PRX22, PCH
1, PCH2, PCV1, PCV2, PLX11, PL
X12, PLX21, and PLX22 are light receiving units of the sensor SNS. These light receiving units are PRX11 and PRX1.
2, PRX21 and PRX22, PCH1 and PCH2, P
CV1 and PCV2, PLX11 and PLX12, PLX2
1 and PLX22 make a pair, respectively, and focus detection area A
RX1, ARX2, ACH, ACV, ALX1, ALX
2, the subject images of the respective focus detection areas by the photographing optical system are re-imaged on these light receiving sections, and a pair of secondary subject images is formed. In addition, each light receiving part,
A charge storage type one-dimensional pixel array including a plurality of pixels is configured.

Next, the operation of the focus detection device will be described. Aperture mask openings RRX11, RRX12, RRX
Reference numerals 21 and RRX22 denote pupil regions EX11 and EX1 of the exit pupil plane EXT of the photographing optical system by the condenser lens FR.
2, projected on EX21, EX22, and the aperture mask openings RCH1, RCH2, RCV1, RCV2 are formed by a condenser lens FC into a pupil area E on an exit pupil plane EXT.
H1, EH2, EV1, EV2, and further, aperture mask openings RLX11, RLX12, RLX21,
RLX22 is provided with a pupil area EX11, EX12, EX21, EX2 of the exit pupil plane EXT by the condenser lens FL.
2 is projected.

Accordingly, the primary image of the subject, which passes through the pupil regions EH1 and EH2 and is formed in the vicinity of the predetermined image forming plane by the photographing optical system, is focused on the focus detection area ACH of the field mask MSK and the apertures RCH1 of the aperture mask RX. The light passes through RCH2 and is re-imaged as a secondary image of the subject on the light receiving units PCH1 and PCH2 of the sensor SNS by the separator lenses SCH1 and SCH2. Similarly, pupil areas EV1, EV2
, The primary image of the subject formed in the vicinity of the predetermined image forming plane by the photographing optical system is the focus detection area ACV of the field mask MSK and the openings RCV1 and RCV of the aperture mask RX.
The light passes through V2 and is re-imaged as a secondary image of the subject on the light receiving sections PCV1 and PCV2 of the sensor SNS by the separator lenses SCV1 and SCV2. Pupil regions EX11, EX
12, the primary image of the subject formed in the vicinity of the planned image formation plane by the photographing optical system passes through the focus detection areas ALX1, ARX1 of the field mask MSK and the openings RLX11, RLX12, RRX11, RRX12 of the aperture mask RX. , Separator lenses SLX11, SLX12, SR
The light receiving unit PL of the sensor SNS by X11 and SRX12
The image is re-imaged on X11, PLX12, PRX11, and PRX12 as a secondary image of the subject. Pupil area EX21, EX
22, the primary image of the subject formed in the vicinity of the predetermined image plane by the photographing optical system passes through the focus detection areas ALX2, ARX2 of the field mask MSK and the openings RLX21, RLX22, RRX21, RRX22 of the aperture mask RX. , Separator lenses SLX21, SLX22, SR
The light receiving section PL of the sensor SNS by X21 and SRX22
It is re-imaged on X21, PLX22, PRX21, PRX22 as a secondary image of the subject.

These light receiving sections PRX11 and PRX12,
PRX21 and PRX22, PCH1 and PCH2, PCV
1 and PCV2, PLX11 and PLX12, and output signals of PLX21 and PLX22, respectively, by performing well-known correlation operation processing, thereby obtaining focus detection areas ARX1 and ARX.
It is possible to detect the focus adjustment state of the imaging optical system in X2, ACH, ACV, ALX1, and ALX2.

With this configuration, the three cross-shaped focus detection areas ARX1 and ARX2, ACH and ACV, A
LX1 and ALX2 are set at the center of the photographing screen P and at the left and right thereof, and the left and right cross focus detection areas are set to be rotated by 45 degrees with respect to the center cross focus detection areas ACH and ACV.

In the focus detection device in which the focus detection area is set as described above, as shown in FIG. 2 (b), a subject having an oblique pattern which cannot be detected or the detection accuracy is deteriorated in the conventional focus detection area is reduced. On the other hand, highly accurate focus detection can be performed in the left and right focus detection areas, and high-precision focus detection can be performed in the center focus detection area for a subject having a vertical or horizontal pattern.

Hereinafter, another focus detection area set by modifying the focus detection optical system shown in FIG. 1 will be described. In the following, description of the focus detection optical system will be omitted. FIG. 3 shows another example of setting the focus detection area. Focus detection area ARH
, ARV, ACX1 and ACX2, ALH and ALV are set orthogonal to each other to form a cross-shaped focus detection area. The focus detection areas ARH and ALH are set in the long side direction of the screen at a position left and right from the center of the screen, and the focus detection areas Arv and ALV are set in the short side direction of the screen at a position left and right from the center of the screen. And the focus detection areas ACX1 and ACX2 are located at the center of the screen in the focus detection areas ARH, ALH, and ARH.
It is set at an angle of 45 degrees with respect to V and ALV. The three cross-shaped focus detection areas are arranged in a straight line in the long side direction of the screen. In order to perform the focus detection with high accuracy as described above, the lengths of the focus detection areas ARH, ARV, ALH, and ALV set at locations other than the center of the screen are determined by the focus detection area ACX1 set at the center of the screen. , ACX2. By setting such a focus detection area, an effect similar to that of the apparatus of the focus detection area shown in FIG.

FIG. 4 shows the light receiving sections PRH1, PRH2, PRV of the sensor SNS corresponding to the focus detection area shown in FIG.
1, PRV2, PCX11, PCX12, PCX21,
PCX22, PLH1, PLH2, PLV1, PLV2
Shows the relationship between the arrangement of and the secondary subject image. Light receiving units PRH1 and PRH2, PRV1 and PRV2, PCX11 and PCX1
2, PCX21 and PCX22, PLH1 and PLH2, P
LV1 and PLV2 form a pair, and the focus detection areas ARH,
ARV, ACX1, ACX2, ALH, and ALV, respectively. The subject image formed in each focus detection area is a pair of light receiving sections PRH1, PRH2, PRV, respectively.
1 and PRV2, PCX11 and PCX12, PCX21 and PCX22, PLH1 and PLH2, PLV1 and PLV2
The image is re-imaged as a pair of secondary subject images on the upper side. The secondary subject image is formed in a range that reflects the shape of the focus detection area indicated by hatching in the figure.

For example, for the light receiving section PLH2, the light receiving section PC
X22 and PCX11, light receiving part PC for light receiving part PRH1
If the directions of the adjacent focus detection areas are different, such as X12 and PCX21, the arrangement direction of the light receiving units on the sensor SNS is different, and the arrangement of the light receiving units can be made compact as shown in the figure. Therefore, the chip size of the sensor SNS can be reduced, and the cost can be reduced.

FIG. 5 shows another example of setting the focus detection area. Focus detection areas ARX1 and ARX2, ACH and AC
V, ALX1 and ALX2 form a cross-shaped focus detection area orthogonal to each other. The focus detection area ACH is set in the long side direction of the screen at the center of the shooting screen P, and the focus detection area ACV is set in the short side direction of the screen at the center of the screen, and the focus detection areas ARX1, ARX2, AL
X1 and ALX2 are located away from the center of the screen.
The focus detection areas ACH and ACV at the center of the screen are set in different directions with respect to each other.
RX1 and ARX2 are focus detection areas ALX, respectively.
1 and ALX2 are set in different directions. The three cross-shaped focus detection areas are arranged in a straight line in the long side direction of the screen. In order to perform the focus detection with high precision as described above, the focus detection areas ARX1, ARX2, and ALX set in places other than the center of the screen.
1 and ALX2 are set shorter than the lengths of the cross-shaped focus detection areas ACH and ACV set in the center of the screen. As described above, since the directions of the respective focus detection areas included in the three cross-shaped focus detection areas are all different,
High-precision focus detection can be performed on a subject pattern at any angle.

FIG. 6 shows another example of setting the focus detection area. Focus detection areas ARX1 and ARX2, ACH and AC
V, ALX1 and ALX2 form a cross-shaped focus detection area orthogonal to each other. The focus detection area ACH is set in the direction of the long side of the screen at the center of the shooting screen P, the focus detection area ACV is set in the direction of the short side of the screen at the center of the screen, and the focus detection areas ARX1 and ARX2 are
Focus detection area A in the upper right part of the shooting screen P
CH and ACV are set to different directions and angles, and the focus detection areas ALX1 and ALX2 are set to different directions and angles to the focus detection areas ACH and ACV, respectively, at the lower left of the screen. Also, the focus detection area AR
X1 and ARX2 are focus detection areas ALX1 and ALX1, respectively.
The same direction and angle are set for ALX2. The focus detection areas ARX1 and ALX1 are set on the radiation from the center of the imaging screen P, and the focus detection areas ARX
Focus detection area ARX orthogonal to 1 and ALX1, respectively
2, ALX2 is inevitably set in the tangential direction of a concentric circle with the center of the photographing screen P. Further, these three cross-shaped focus detection areas are arranged in a straight line in a diagonal direction of the photographing screen P. In order to perform the focus detection with high accuracy as described above, the focus detection areas ARX1, ARX2, ALX1, and ALX2 set at positions other than the center of the photographing screen P.
Is the focus detection area AC set in the center of the screen.
H and ACV are set shorter than the length. Thus, 3
In the projection of the two cross-shaped focus detection areas in the long side direction and the short side direction of the screen, the focus detection areas are set so that the portions overlapping each other are reduced, so that the ability to capture vertical and horizontal object patterns is improved.

FIG. 7 shows another example of setting the focus detection area. Focus detection areas ARH and AVR, ACH and ACV,
ALH and ALV are orthogonal to each other to form a cross-shaped focus detection area. The focus detection area ACH is the shooting screen P
In the center of the screen, the focus detection areas ARH and ALH are set on the left and right sides of the screen in the long side direction of the screen, and the focus detection area ACV is set in the center of the screen in the short side direction of the screen. , Focus detection area AR
V and ALV are set on the left and right sides of the screen in the short side direction of the screen. Length WRL of focus detection areas ARH and ALH set on the left and right of the screen to perform highly accurate focus detection
H and the length WRL of the focus detection areas ARV and ALV
V is a focus detection area ACH, A set in the center of the screen.
The lengths of the CVs are set shorter than the lengths WCH and WCV, respectively. Further, the length WCV of the focus detection area ACV set in the short side direction at the center of the screen is shorter than the length WCH of the focus detection area ACH set in the long side direction at the center of the screen.
The length ratio is set substantially equal to the aspect ratio of the screen.

As described above, by setting the length ratio of the focus detection areas set in the long side direction and the short side direction of the screen at the center of the photographing screen P to be equal to the aspect ratio of the photographing screen P, the focal point is obtained. The probability that the subject can be captured in the focus detection area at the time of detection increases, and the photographing screen P in the focus detection area
, The usability is improved when a main subject is selected from a plurality of subjects. Furthermore, the length WRLV of the focus detection areas ALH and ARH set in the long side direction is based on the length WRLV of the focus detection areas ALV and ALV set in the short side direction on the left and right of the shooting screen P.
H is set short. As described above, when the focus detection area is set at a place other than the center of the imaging screen P, the focus set on the radiation from the center of the screen is larger than the length of the focus detection area set in the tangential direction of the concentric circle with the center of the screen. By setting the length of the detection area to be short, deterioration of the focus detection accuracy can be prevented as described above. Further, as described above, except for the center of the imaging screen P, the optical performance of the focus detection optical system in the focus detection area set on the radiation from the center of the screen is the focus detection area set in the tangential direction of a concentric circle with the center of the screen. Is inferior to the optical performance of the focus detection optical system of
When performing focus detection, the focus detection result of the focus detection area set in the tangential direction of the concentric circle with the center of the screen may be prioritized over the focus detection result of the focus detection area set on the radiation from the center of the screen. For example, only when it is determined that the focus cannot be detected in the focus detection area set in the tangential direction of the concentric circle with the center of the screen, the focus may be detected in the focus detection area set on the radiation from the center of the screen.

FIG. 8 shows the light receiving sections PRH1, PRH2, PR on the sensor SNS corresponding to the focus detection area shown in FIG.
V1, PRV2, PCH1, PCH2, PCV1, PC
The relationship between the arrangement of V2, PLH1, PLH2, PLV1, PLV2 and the secondary subject image is shown. Light receiving sections PRH1 and PRH
2, PRV1 and PRV2, PCH1 and PCH2, PCV
1, PCV2, PLH1 and PLH2, PLV1 and PLV
2 make a pair, focus detection areas ARH, ARV, AC
H, ACV, ALH, and ALV, respectively. The subject image formed in each focus detection area is a pair of light receiving sections PRH1 and PRH2, PRV1 and PRV2, PC
H1 and PCH2, PCV1 and PCV2, PLH1 and PL
The image is re-imaged on H2, PLV1 and PLV2 as a pair of secondary object images. The secondary subject image is formed in a range that reflects the shape of each focus detection area indicated by hatching in the figure.
The light receiving units PLH2 and PCH1, PCH2 and PRH1 adjacent to the center focus detection area and the left and right focus detection areas are:
It is necessary to provide a gap between the light receiving units to some extent so as not to receive the secondary subject images in the other focus detection areas.

FIG. 9 shows the light receiving sections PRH1, PRH2, PRV1, PRV2, PCH1, and PRCH1 of the sensor SNS shown in FIG.
PCH2, PCV1, PCV2, PLH1, PLH2,
Details of PLV1 and PLV2 will be described. The light receiving section PRH
1, PRH2, PRV1, PRV2, PCH2 are light receiving units PLH1, PLH2, PLV1, PLV2, PCH1.
And the sensor SNS are symmetric with respect to the center line in the long side direction, and illustration and description thereof are omitted. A pair of light receiving sections PCV1 and PCV2 corresponding to the focus detection area ACV set in the center of the photographing screen P in the direction of the screen short side has a pixel width HC.
V, and a pixel pitch KCV. A pair of light receiving units PCH1 and PCH2 corresponding to the focus detection area ACH set in the screen long side direction at the center of the screen has a pixel width HCH and a pixel pitch KCH. Light receiving units PLV1 and PL corresponding to the focus detection area ALV set in the screen short side direction on the left side of the screen
V2 has a pixel width HRLV and a pixel pitch KRLV. Of the pair of light receiving units PLH1 and PLH2 corresponding to the focus detection area ALH set in the screen long side direction on the left side of the screen, the light receiving unit PL located far from the center of the sensor SNS
H1 has a pixel width HRLH1 and a pixel pitch KRLH1. Of the light receiving portions PLH1 and PLH2 corresponding to the focus detection area ALH set in the screen long side direction on the left side of the screen, the light receiving portion PLH2 at a position close to the sensor SNS has a pixel width HRLH2 and a pixel pitch KRLH2.

Usually, in the peripheral portion of the screen, the amount of light in the peripheral portion is reduced due to the characteristics of the photographing optical system. Also, when focus detection is performed at the periphery of the screen, the F of the light beam for focus detection at the periphery of the screen is used so that vignetting does not occur with a lens having a large F number.
Since the value is set to be larger than the F value of the light beam for focus detection at the center of the screen, the illuminance on the light receiving unit further decreases. Here, the F value of the light beam for focus detection is determined by the pupil region EH1, shown in FIG.
The F value of the circumcircle of EH2, EV1, and EV2. Therefore, based on the pixel widths HCH and HCV of the light receiving sections PCH1 and PCH2 and PCV1 and PCV2 corresponding to the focus detection areas ACH and ACV at the center of the screen, the focus detection area AL on the left side of the screen.
Light receiving units PLH1, PLH2, PL corresponding to H, ALV
V1, PLV2 pixel width HRLH1, HRLH2, HR
By setting the LV large, it is possible to compensate for a decrease in the amount of light on the light receiving unit around the screen.

As described above, normally, when focus detection is performed around the screen, the F value of the light beam for focus detection around the screen is set at the center of the screen so that vignetting does not occur with a lens having a large F number. Is made larger than the F value of the light beam for focus detection in step (1). On the other hand, as shown in FIG. 37, when focus detection is performed in the radiation direction from the center of the imaging screen P, the vignetting condition becomes more severe than when focus detection is performed in the tangential direction of a concentric circle with the screen center. It is necessary to make the F value of the light beam for focus detection in the direction (here, the long side direction of the screen) larger than the F value of the light beam for focus detection in the tangential direction of the circle (here, the short side direction of the screen). Therefore, the light receiving sections PLH1, PH
Illuminance on LH2 decreases. Therefore, the light receiving unit PLV corresponding to the focus detection area ALV in the screen short side direction on the left side of the screen
The light receiving unit PLH corresponding to the focus detection area ALH in the long side direction of the screen on the left side of the screen from the pixel width HRLV of 1, PLV2
By setting the pixel widths HRLH1 and HRLH2 of the PLH1 and PLH2 to be large, it is possible to compensate for the imbalance of the light amount in the setting direction of the focus detection area around the screen.

Normally, when focus detection is performed in the radial direction from the center of the screen around the screen, as shown in FIG.
And the condenser lenses FR, F
The asymmetry is further strengthened due to the eccentricity of the optical axis AX of L toward the center of the screen. As described above, due to the difference in magnification between the pair of re-imaging optical systems and the imbalance in light amount, the light receiving portion PLH
1, the illuminance on PLH2 becomes unbalanced. Therefore, of the pair of light receiving units PLH1 and PLH2 corresponding to the focus detection area ALH in the long side direction of the screen on the left side of the screen, the light receiving unit P
From the pixel width HRLH2 of LH2, the other light receiving unit PLH1
By setting the pixel width HRLH1 to be large, it is possible to compensate for the light amount imbalance caused by the asymmetry of the re-imaging optical system in the focus detection area set in the radial direction around the screen.

At the periphery of the screen, the optical performance of the photographing optical system deteriorates, and since the peripheral focus detection optical system is not on the optical axis AX of the photographing optical system, the re-imaging performance is inferior to that of the central focus detection optical system. . Therefore, the light receiving units PCH1, PCH at the center of the screen
Pixel pitch KCH, KC of CH2, PCV1, PCV2
V, light receiving units PLH1, PLH2, PLV on the left side of the screen
1, PLV2 pixel pitch KRLH1, KRLH2, K
By finely setting the RLV, it is possible to improve the focus detection accuracy and compensate for a decrease in the optical performance of the focus detection optical system for the screen periphery.

The focus detection optical system in the radiation direction from the center of the screen (here, the long side direction of the screen) is more asymmetric than the focus detection optical system in the tangential direction of the concentric circle with the center of the screen (here, the short side direction of the screen). The optical performance is inferior because of high performance. Therefore, the pixel pitch KRLV of the light receiving units PLV1 and PLV2 corresponding to the focus detection area ALV in the screen short side direction on the left side of the screen.
The pixel pitch KRL of the light receiving units PLH1 and PLH2 corresponding to the focus detection area ALH in the screen long side direction on the left side of the screen
The focus detection accuracy can be improved by setting H1 and KRLH2 small, and the imbalance in the optical performance of the focus detection optical system depending on the setting direction of the focus detection area around the screen can be compensated.

In the case where focus detection is performed in the radial direction from the center of the screen at the periphery of the screen, a pair of refocusing optical systems for focus detection are arranged asymmetrically with respect to the optical axis of the photographing optical system as shown in FIG. As a result, the asymmetry is further increased due to the eccentricity of the optical axis of the condenser lens toward the center of the screen. Such asymmetry causes a difference in magnification between the pair of re-imaging optical systems and the like, and imbalance occurs in the images formed on the light receiving units PLH1 and PLH2. Therefore, of the pair of light receiving portions PLH1 and PLH2 corresponding to the focus detection area ALH in the screen long side direction on the left side of the screen, the pixel pitch KRLH2 of the light receiving portion PLH2 is shifted from the pixel pitch KRLH2 of the other light receiving portion PLH1.
RLH1 is finely set to improve focus detection accuracy,
It is possible to compensate for the imbalance in optical performance due to the asymmetry of the focus detection optical system in the focus detection area set in the radial direction around the screen.

As described above, by setting the pixel pitch and the pixel width of each light receiving section on the sensor SNS so as to compensate for the deterioration of the performance of the optical system, the luminance levels in the central and peripheral focus detection areas are almost the same. When the subject is captured,
Since the illuminance imbalance of the light receiving unit is corrected, it is possible to obtain output signals of the light receiving units having the same output level in substantially the same charge accumulation time, and it becomes easy to process the output signal of the sensor SNS. Further, it is possible to make the focus detection accuracy between the center of the screen and the peripheral portion almost the same.

In the above embodiment, the decrease in the optical performance was corrected by reducing the pixel pitch. On the contrary, the portion where the optical performance was reduced was made coarser by reducing the number of pixels to improve the processing speed. You may make it do.

FIG. 10 shows the focus detection area AL shown in FIG.
13 shows another setting example of the pixel pitch and the pixel width of the pair of light receiving units PLH1 and PLH2 corresponding to H. When performing focus detection around the screen in the radiation direction from the center of the screen,
As shown in FIG. 37, a pair of re-imaging optical systems for focus detection are arranged asymmetrically with respect to the optical axis AX of the photographing optical system, and further asymmetrical due to eccentricity of the optical axis of the condenser lens toward the center of the screen. Becomes stronger. Due to such asymmetry, the distortion characteristics of the pair of re-imaging systems are shown in FIG.
As shown in (a) and (b), imbalance occurs. Therefore, of the pair of light receiving units PLH1 and PLH2 corresponding to the focus detection area ALH in the long side direction of the screen on the left side of the screen, the light receiving unit P
The pixel pitch of the light receiving unit PLH2 is changed for each location in accordance with the distortion characteristic of the re-imaging system corresponding to LH2, and the light receiving unit PLH1 is controlled in accordance with the distortion characteristic of the re-imaging system corresponding to the light receiving unit PLH1. By changing the pixel pitch for each location, the optics caused by the asymmetry of the pair of re-imaging optical systems corresponding to the focus detection area set in the radial direction from the center of the screen around the screen as shown in FIG. Compensates for performance imbalances. As a result, focus detection accuracy around the screen is improved.

FIG. 11 shows another setting example of the light receiving section on the sensor SNS corresponding to the focus detection area shown in FIG. Note that the light receiving units PRH1, PRH2, PRV1, PRV2 corresponding to the focus detection areas ARH, ARV on the right side of the screen are targeted with respect to the horizontal center line of the sensor SNS.
Illustration and description thereof are omitted. The light receiving units PCV1 and PCV2 corresponding to the focus detection area ACV set in the screen short side direction at the center of the screen have a pixel tilt angle LCV. The light receiving units PCH1 and PCH2 corresponding to the focus detection area ACH set in the screen long side direction at the center of the screen have a pixel tilt angle LCH. The light receiving unit PLV corresponding to the focus detection area ALV set in the screen short side direction on the left side of the screen
1, PLV2 has a pixel inclination angle LRLV. The light receiving units PLH1 and PLH2 corresponding to the focus detection area ALH set in the screen long side direction on the left side of the screen have a pixel tilt angle LRLH.

Conventionally, there has been known a method of optically cutting high-frequency components by tilting pixels since high-frequency components of an image generally adversely affect focus detection accuracy when re-imaging performance is good. . However, usually, the optical performance of the photographing optical system is deteriorated in the peripheral portion of the screen, and the peripheral focus detection optical system is not on the optical axis AX of the photographing optical system, and the re-imaging performance is inferior to that of the central focus detection optical system. Therefore, the high-frequency component has already been considerably cut off, and the inclination angle of the pixel of the light receiving unit corresponding to the focus detection area in the peripheral portion is set to be the same as the inclination angle of the pixel of the light receiving unit corresponding to the central focus detection area. Focus detection accuracy deteriorates. Therefore, the inclination directions of the pixels of the light receiving units PCH1 and PCH2 corresponding to the focus detection area ACH in the screen long side direction at the center of the screen, and the light receiving units PLH1 and PLH2 corresponding to the focus detection area ALH in the screen long side direction on the left side of the screen. The tilt direction of the pixel is set so as to be relatively different. On the other hand, the light receiving unit PC corresponding to the focus detection area ACV in the screen short side direction at the center of the screen
The light receiving section PLV corresponding to the tilt direction of the pixels of V1 and PCV2 and the focus detection area ALV in the screen short side direction on the left side of the screen.
1, the inclination direction of the pixel of PLV2 is set to be relatively different. Light receiving units PCH1, PCH2, P at the center of the screen
From the inclination angles LCH and LCV of the pixels of CV1 and PCV2, the light receiving sections PLH1, PLH2, PLV1, P on the left of the screen are displayed.
By setting the inclination angles LRLH and LRLV of the pixel of LV2 to be small, the focus detection accuracy can be improved, and the deterioration of the optical performance of the focus detection optical system for the periphery of the screen can be compensated.

When focus detection is performed in the radiation direction from the center of the screen, the focus detection optical system in the radiation direction (here, the long side direction of the screen) uses the tangential direction of the concentric circle with the center of the screen (here, the screen). Since the asymmetry is larger than that of the focus detection optical system (short side direction) and the re-imaging performance is inferior, the high-frequency components have already been considerably cut off, and the inclination angle of the pixel of the light receiving unit corresponding to the focus detection area in the radial direction has been reduced. If the pixel inclination angle of the light receiving unit corresponding to the focus detection area in the tangential direction is set to the same angle, the focus detection accuracy is deteriorated. Therefore, the light receiving unit PL corresponding to the focus detection area ALV in the short side direction of the screen on the left side of the screen
The tilt angles LRLH of the pixels of the light receiving units PLH1 and PLH2 corresponding to the focus detection area ALH in the direction of the longer side of the screen on the left side of the screen are set smaller than the tilt angles LRLV of the pixels of V1 and PLV2, thereby improving the focus detection accuracy. It is possible to compensate for a decrease in the optical performance of the focus detection optical system due to the arrangement direction of the focus detection areas in the peripheral portion of the screen.

Also, by setting the inclination directions of the pixels of the light receiving section corresponding to the focus detection areas arranged in the same direction at the center and the periphery of the photographing screen P, how the object pattern is inclined However, focus detection can be performed in any one of the focus detection areas in the center or the periphery. That is, in order to obtain a highly accurate focus detection result, the method of optically cutting the high frequency component of the subject image by tilting the pixel does not work when the subject image is tilted by the same angle as the tilt angle of the pixel. In order to perform high-precision focus detection by setting the inclination direction of the pixel of the light receiving unit different between the center and the peripheral part, and cutting the high-frequency component with either light receiving unit for such an object Can be.

As described above, since the inclination angles of the pixels of the light receiving section corresponding to the focus detection areas of the center and the periphery are set to be different, the focus detection accuracy of the center of the screen and the periphery and the tangent of the periphery are determined. The focus detection accuracy of the focus detection areas in the direction and the radiation direction can be made substantially the same.

A similar effect can be obtained by inclining only the pixels of the light receiving section corresponding to the central focus detection area and not tilting the pixels of the light receiving section corresponding to the peripheral focus detection area. .

FIG. 12 shows another example of setting the focus detection area. The arrangement of the focus detection area in the center of the screen is shown in FIG.
This is the same as the arrangement of the central focus detection area shown in FIG. Focus detection area ACH, ACV
Forms a cross-shaped focus detection area, and focus detection area A
RH1, ARH2, ARV, ALH1, ALH2, AL
V forms a U-shaped focus detection area. Focus detection areas ACH, ACV, focus detection areas ARH1, AR
H2, ARV, focus detection area ALH1, ALH2, A
In the LV, each focus detection area is orthogonal to each other.
The focus detection area ACH is set at the center of the screen in the direction of the longer side of the screen, and the focus detection areas ARH1 and ARH2 are set at the right of the screen in the direction of the longer side of the screen.
H2 is set on the left side of the screen in the long side direction of the screen. Further, the focus detection area ACV is set in the screen short side direction at the center of the screen, and the focus detection areas ARV and ALV are set in the left and right sides of the screen in the screen short side direction.

In order to perform highly accurate focus detection, the length WC of the focus detection areas ACH and ACV set at the center of the screen
H, WCV, length WRL of focus detection areas ARH1, ARH2, ALH1, ALH2 set on the left and right of the screen
H and the length WRL of the focus detection areas ARV and ALV
V is set short. In addition, from the length WRLV of the focus detection areas ALV and ARV set in the tangential direction of the screen center and the concentric circle on the left and right of the screen (here, the short side direction of the screen).
Radiation direction from the center of the screen (here, the long side of the screen)
Focus detection areas ALH1, ALH2, AR set in
The length WRLH of H1 and ARH2 is set short. As described above, when the focus detection area is set at a place other than the center of the screen, the length of the focus detection area set in the radial direction from the screen center is larger than the length of the focus detection area set in the tangential direction of the screen center and the concentric circle. By reducing the length, it is possible to prevent the focus detection accuracy from deteriorating as described above.

FIG. 13 shows the light receiving sections PRH11, PRH1 of the sensor SNS corresponding to the focus detection area shown in FIG.
2, PRH21, PRH22, PRV1, PRV2, P
CH1, PCH2, PCV1, PCV2, PLH11,
PLH12. PLH21, PLH22, PLV1, PL
4 shows the relationship between the arrangement of V2 and the secondary subject image. Light receiver PR
H11 and PRH12, PRH21 and PRH22, PRV
1 and PRV2, PCH1 and PCH2, PCV1 and PCV
2, PLH11 and PLH12, PLH21 and PLH2
2, the focus detection areas ARH1, ARH2, Arv, ACH, ACV,
Corresponds to ALH1, ALH2, ALV. The subject images formed in each focus detection area are re-formed as a pair of secondary subject images on a pair of corresponding light receiving units. 2
The next subject image is formed in a range that reflects the shape of the focus detection area indicated by hatching in the figure.

As described above, since the shapes of the focus detection areas on the left and right sides of the screen are U-shaped, an adjacent light receiving section (PLH) is located between the center focus detection area and the left and right focus detection areas.
21 and PLH22 and PCH1, PCH2 and PRH1
1 and PRH 12) have a nested structure, so that even if the gap between the light receiving sections is small, they do not receive the secondary subject images in other focus detection areas. Therefore, the chip size of the sensor SNS can be reduced as compared with the focus detection area shown in FIG. 7, and the cost can be reduced.

FIG. 14 shows another example of setting the focus detection area. The focus detection area ACH, ARV at the center of the screen
Are the same as those in the central focus detection area shown in FIG. 7, and the differences will be mainly described. Focus detection area ACH, ACV
Forms a cross-shaped focus detection area and a focus detection area AR
H, ARV, ALH, and ALV form a U-shaped focus detection area. Focus detection area ACH and ACV, ARH
And ARV and ALH and ALV are orthogonal to each other. The focus detection area ACH is set at the center of the screen in the direction of the longer side of the screen.
The CV is set in the center of the screen in the short side direction of the screen, and the focus detection areas ARV and ALV are set in the left and right sides of the screen in the short side direction of the screen.

In order to perform the focus detection with high accuracy, the length WC of the focus detection areas ACH and ACV set at the center of the screen
The length WRLH of the focus detection areas ARH and ALH and the length WRLV of the focus detection areas ARV and ALV set on the left and right sides of the screen are set shorter than H and WCV, respectively. Further, the radiation direction from the center of the screen (here, of the screen) is determined by the length WRLV of the focus detection areas ALV and ARV set in the tangential direction of the center of the screen (here, the short side direction of the screen) on the left and right sides of the screen. The length WRLH of the focus detection areas ALH, ARH set in the (long side direction) is set short.

As described above, when the focus detection area is set at a place other than the center of the screen, the focus detection area is set in the radial direction from the screen center, based on the length of the focus detection area set in the tangential direction of the concentric circle with the screen center. By reducing the length of the focus detection area, it is possible to prevent the focus detection accuracy from deteriorating as described above. Further, since the shape of the left and right focus detection areas is shaped like a triangle, focus detection can be performed in both the vertical and horizontal directions at the left and right ends of the shooting screen P, and a subject located near the left or right end of the screen can be detected. Focus detection can be performed by reliably capturing in the focus detection area.

FIG. 15 shows the light receiving sections PRH1, PRH2, PR on the sensor SNS corresponding to the focus detection area in FIG.
V1, PRV2, PCH1, PCH2, PCV1, PC
7 shows the relationship between the arrangement of V2, PLH1, PLH2, PLV1, and PLV2 and the secondary subject image. Light receiver PRH1 and PR
H2, PRV1 and PRV2, PCH1 and PCH2, PC
V1 and PCV2, PLH1 and PLH2, PLV1 and PL
V2 forms a pair, focus detection areas ARH, Arv, AC
H, ACV, ALH, and ALV. The subject images formed in each focus detection area are re-formed as a pair of secondary subject images on each of the pair of light receiving units. The secondary subject image is formed in a range that reflects the shape of the focus detection area indicated by hatching in the figure.

Since the shape of the left and right focus detection areas is shaped like a triangle, the positions of the light receiving units located at the left and right ends on the sensor SNS are centered compared to the setting of the light receiving units of the sensor SNS shown in FIG. Therefore, the chip size becomes smaller than that of the sensor SNS shown in FIG. 8 and the cost can be reduced.

FIG. 16 shows another example of setting the focus detection area. Focus detection area ARH, ARV, ALH, ALV
Form a cross-shaped focus detection area orthogonal to each other. The focus detection areas ARH and ALH are set on the left and right sides of the screen in the direction of the longer side of the screen.
Are set in the direction of the screen short side on the left and right of the screen. These two cross-shaped focus detection areas are arranged on a straight line passing through the center of the screen in the long side direction of the screen, and are set symmetrically with respect to the center of the screen. In addition, the radiation direction from the center of the screen (here, of the screen) is determined by the length WV of the focus detection areas ALV and ARV set in the tangential direction (here, the short side direction of the screen) of the screen center on the left and right sides of the screen. The length WH of the focus detection areas ALH, ARH set in the (long side direction) is set longer.

As described above, by setting two cross-shaped focus detection areas other than the center of the photographing screen P,
Focus detection in a screen can be efficiently performed with a small focus detection area. In addition, two cross-shaped focus detection areas are arranged in the long side direction of the screen, and the length WH of the focus detection areas ALH and ARH parallel to these arrangement directions is set longer than the other focus detection areas ALV and ARV. Therefore, focus detection can be performed in a state where there is almost no gap in the long side direction of the screen. Thus, a cross-shaped focus detection is always performed on a main subject located at a position other than the center of the screen in the direction of the long side of the screen (for example, a face in a bust shot in vertical shooting) or a subject moving in the long side of the screen. An area can be captured and focus detection can be performed reliably. Furthermore, since the two cross-shaped focus detection areas are set symmetrically with respect to the center of the screen, the focus detection operation can always be performed with the same usability regardless of the photographing posture of the camera (upside-down rotation during vertical position photographing). .

Further, even when the photographing light beam is deflected by the sub-mirror toward the bottom of the mirror box and a focus detection module is set on the bottom of the body, it is better to arrange the focus detection areas in the long side direction of the screen to configure the sub-mirror and detect the focus. The degree of freedom of the module arrangement space is great and advantageous.

FIG. 17 shows another example of setting the focus detection area. Focus detection area AUH, AUV, ADH, ADV
Form cross-shaped focus detection areas orthogonal to each other. The focus detection areas AUH and ADH are set in the longitudinal direction of the screen above and below the center of the screen.
V and ADV are set in the direction of the short side of the screen above and below the center of the screen. These two cross-shaped focus detection areas are arranged on a straight line passing through the center of the screen in the short side direction of the screen, and are set symmetrically with respect to the center of the screen. Also, based on the focus detection areas AUV and ADV set in the radiation direction from the screen center (here, the short side direction of the screen) above and below the screen center, the tangential direction of the concentric circle with the screen center (here, the screen) Long side direction)
Length WH of focus detection area AUH, ADH set in
Is set long.

As described above, by setting two cross-shaped focus detection areas in places other than the center of the screen, focus detection in the screen can be efficiently performed with a small number of focus detection areas. Also, since two cross-shaped focus detection areas are arranged in the short side direction of the screen, focus detection can be performed in a state where there is almost no gap in the short side direction of the screen, and the focus detection area exists outside the center in the short side direction of the screen. A main subject (such as a face or an eye during a bust shot in horizontal position shooting) or a subject moving in the direction of the short side of the screen can always be captured in the focus detection area and focus detected. Furthermore, since the two cross-shaped focus detection areas are set symmetrically with respect to the center of the screen, the focus detection operation can always be performed with the same usability regardless of the photographing posture of the camera (upside-down rotation during vertical position photographing). . When the focus detection area is set at a position other than the center of the screen, the length of the focus detection area set in the radial direction from the screen center is larger than the length of the focus detection area set in the tangential direction of the concentric circle with the screen center. By setting the length to be short, it is possible to prevent the focus detection accuracy from deteriorating as described above.

FIG. 18 shows another example of setting the focus detection area. Focus detection area ARH, ARV, ALH, ALV
Form cross-shaped focus detection areas orthogonal to each other. The focus detection areas ARH and ALH are set on the left and right sides of the screen in the direction of the longer side of the screen.
V is set on the left and right sides of the screen in the direction of the short side of the screen. These two
The two cross-shaped focus detection areas are arranged on a straight line passing through the center of the screen in a diagonal direction of the screen, and are set symmetrically with respect to the center of the screen. Further, the length WH of the focus detection areas ALH and ARH set in the long side direction is set longer than the length WV of the focus detection areas ALV and ALV set in the short side direction of the screen on the left and right sides of the screen.

As described above, by setting two cross-shaped focus detection areas at places other than the center of the screen, focus detection within the screen can be efficiently performed with a small number of focus detection areas. Further, two cross-shaped focus detection areas are arranged in the diagonal direction of the screen, and the length WH of the focus detection areas ALH and ARH set in the long side direction of the screen is changed to the focus detection area ALV set in the short side direction of the screen. , ARV are set to be longer than the length WV, so that the projections of the two cross-shaped focus detection areas in the screen long side direction and the screen short side direction do not overlap each other. Furthermore, because the projected part in the long side direction of the screen is longer than the short side direction, focus detection can be efficiently performed in screens with different lengths in the vertical and horizontal directions, and the capture performance for vertical and horizontal object patterns is improved. I do. In addition, 2 symmetrically with respect to the center of the screen
Since the two cross-shaped focus detection areas are set, the focus detection operation can be performed with the same usability regardless of the photographing posture of the camera (upside-down rotation in vertical position photographing).

FIG. 19 shows another example of setting the focus detection area. Focus detection area ARH, ARV, ALH, ALV
Form cross-shaped focus detection areas orthogonal to each other. The focus detection areas ARH, ALH are set on the left and right sides of the screen in the direction of the long side of the screen, and the focus detection areas ARH, A
LV is set on the left and right sides of the screen in the direction of the screen short side. These two cross-shaped focus detection areas are arranged closer to each other on a straight line passing through the center of the screen in the diagonal direction of the screen than the cross-shaped focus detection area shown in FIG. 18, and are set symmetrically with respect to the center of the screen. Further, the length of the focus detection areas ALH, ARH set in the long side direction is set longer than the length of the focus detection areas ALV, ALV set in the short side direction on the left and right sides of the screen.

As described above, by setting two cross-shaped focus detection areas in places other than the center of the screen, it is possible to efficiently perform focus detection in the screen with a small number of focus detection areas. In addition, since the center of the screen is almost surrounded by the four focus detection areas, even in a shooting composition in which the main subject is set at the center of the screen, the subject can be captured in any of the four focus detection areas and the focus can be reliably detected. Can be.
That is, even if the focus detection area is not set at the center of the screen, it is possible to perform focus detection on a subject located at the center of the screen at a level that does not pose a practical problem. Furthermore, since the two cross-shaped focus detection areas are set symmetrically with respect to the center of the screen, the focus detection operation can be performed with the same usability regardless of the photographing posture of the camera (upside-down rotation in vertical position photographing).

FIG. 20 shows the light receiving sections PRH1, PRH2, PH of the sensor SNS corresponding to the focus detection area shown in FIG.
RV1, PRV2, PLH1, PLH2, PLV1, P
4 shows the relationship between the LV2 arrangement and the secondary subject image. Receiver P
RH1 and PRH2, PRV1 and PRV2, PLH1 and P
LH2, PLV1 and PLV2 form a pair and correspond to the focus detection areas ARH, ARV, ALH and ALV. The subject images formed in each focus detection area are re-formed as a pair of secondary subject images on each of the pair of light receiving units. The secondary subject image is formed in a range that reflects the shape of the focus detection area indicated by hatching in the figure.

As described above, the two cross-shaped focus detection areas are set side by side on the diagonal line of the screen. Accordingly, the area of the circumscribed polygon of the light receiving portion can be reduced, and the chip size of the sensor SNS can be reduced, thereby reducing the cost.

FIG. 21A shows another example of setting the focus detection area. Focus detection area ARH, ARV, ACH,
ACV, ALH, and ALV are each orthogonal to each other and 3
The two cross-shaped focus detection areas are formed, and are set so as not to be aligned in a line other than the center of the screen. The focus detection areas ALH and ALV are set at positions deviated leftward from the center of the screen in the direction of the longer side of the screen.
CH and ACV are set at positions deviated upward from the center of the screen in the direction of the short side of the screen, and the focus detection areas ARH and AVR
Is set to a position shifted to the right in the long side direction and below the short side direction from the center of the screen. Focus detection area ACH, A
RH and ALH are set in the long side direction of the screen, and the focus detection areas ACV, ARV and ALV are set in the short side direction of the screen.

As described above, since the three cross-shaped focus detection areas are efficiently set so as not to be aligned on a straight line in the screen, the portrait photographing in the horizontal position is performed as shown in FIG. Sometimes, focus detection can be performed on a person's face. Also, during portrait shooting in a vertical position, FIG.
As shown in (1), focus detection can be performed on a person's face. Further, the projections of the three cross-shaped focus detection areas in the long side direction and short side direction of the screen are set so as not to overlap each other as shown in FIG. Therefore, it is possible to efficiently capture a subject having a vertical and horizontal pattern that is statistically present in a large amount in the natural world as shown in FIG. Further, for example, it is more likely that a subject having an oblique pattern as shown in FIG. 23B can be captured in any one of the plurality of focus detection areas. In this embodiment, the projection of the focus detection area is set so as not to completely overlap. However, the same effect can be obtained even if the projection is slightly overlapped. Furthermore, although each focus detection area included in the three cross-shaped focus detection areas is set in the long side direction or short side direction of the screen, the focus detection areas may be set so as not to be parallel to each other.

FIG. 24 shows another example of setting the focus detection area. Focus detection areas ARX1, ARX2, ACH, A
CV, ALH, and ALV are set so as to form three cross-shaped focus detection areas orthogonal to each other, and not to be aligned in a line other than the center of the screen. The cross-shaped focus detection areas ALH and ALV are set at positions deviated leftward from the center of the screen in the long side direction of the screen, and the cross-shaped focus detection areas ACH and ACV are deviated upward from the center of the screen in the short side direction of the screen. The cross focus detection area ARX
1, ARX2 is set at a position deviated to the lower right of the screen diagonally from the center of the screen. Focus detection area ACH, AL
H is set in the long side direction of the screen, and the focus detection areas ACV,
ALV is set in the short side direction of the screen, and the focus detection area AR
X2 is set in a radial direction from the center of the screen, and the focus detection area ARX1 is set in a tangential direction of a concentric circle with the center of the screen. Furthermore, in order to perform high-precision focus detection precision, a radiation direction from the center of the screen is set based on the length of the focus detection areas ACH, ALV, and ARX1 set in a tangential direction of a circle concentric with the center of the screen at a place other than the center of the screen. The length of the focus detection areas ACV, ARX2, and ALH thus set is set short.

As described above, at a position other than the center of the screen, the length of the focus detection area set in the radial direction from the center of the screen is smaller than the length of the focus detection area set in the direction tangent to the center of the screen. By setting the length to be short, it is possible to prevent the focus detection accuracy from being deteriorated as described above. In addition, since the three cross-shaped focus detection areas are efficiently set so as not to be aligned on a straight line in the photographing screen, the focus of the face position is surely focused when photographing portrait photographs in vertical and horizontal positions. Can be detected. Furthermore, since the projections of the three cross-shaped focus detection areas in the long side direction and short side direction of the screen are set so that overlapping portions are reduced, objects having a vertical and horizontal pattern which are statistically large in nature can be efficiently extracted. Can be captured. Further, it is more likely that a subject having an oblique pattern can be captured in any of the plurality of focus detection areas.

FIG. 25 shows another example of setting the focus detection area. Focus detection areas ARX1, ARX2, ACH, A
The CV, ALX1, and ALX2 form three cross-shaped focus detection areas orthogonal to each other, and are set so as not to be aligned in a line other than the center of the screen. The cross-shaped focus detection areas ALX1 and ALX2 are set at positions deviated leftward from the center of the screen in the long-side direction of the screen, and the cross-shaped focus detection areas ACH and ACV are deviated upward from the center of the screen in the short-side direction of the screen. The cross-shaped focus detection areas ARX1 and ARX2 are set at positions deviated from the center of the screen to the lower right in the diagonal direction of the screen. Further, the focus detection area ACH is set in the long side direction of the screen, and the focus detection area ACH is set.
CV is set in the direction of the short side of the screen, and the focus detection area ARX
1, ARX2 is set in the screen diagonal direction. Further, each focus detection area ALX1, ALX2, ACH, ACV,
ARX1 and ARX2 are set so as not to be parallel to each other.

As described above, since the three cross-shaped focus detection areas are efficiently set so as not to be aligned on a straight line within the screen, the face can be reliably detected even when portrait portrait and horizontal portrait photographs are taken. Can be detected. In addition, since the projections of the three cross-shaped focus detection areas in the long side direction and the short side direction of the screen are set so that overlapping portions are reduced, subjects having a vertical and horizontal pattern which are statistically large in nature can be efficiently processed. Can be captured.
Further, the possibility of capturing an object having an oblique pattern in any one of the plurality of focus detection areas is increased. Further, since the focus detection areas included in the three cross-shaped focus detection areas are set so as not to be parallel to each other, focus detection can be performed on a subject pattern at any angle.

FIG. 26 shows another example of setting the focus detection area. Focus detection areas ARX1, ARX2, ACH, A
The CV, ALX1, and ALX2 form three cross-shaped focus detection areas that are orthogonal to each other, and are respectively set at vertices of a regular triangle whose base is parallel to the long side of the screen and whose center is the center of the screen. You. The cross-shaped focus detection areas ALX1 and ALX2 are set at positions deviated from the center of the screen to the lower left of the screen, and the cross-shaped focus detection areas ACH and AX
The CV is set at a position deviated upward from the center of the screen on the short side of the screen, and the cross-shaped focus detection areas ARX1 and ARX2 are set at positions deviated from the center of the screen toward the lower right of the screen. The focus detection area ACH is set in the long side direction of the screen,
The focus detection area ACV is set in the direction of the short side of the screen, the focus detection areas ALX1 and ARX2 are set in the direction of the line connecting the vertex of the triangle and the center of the screen (radiation direction from the center of the screen), and the focus detection areas ALX2 and ARX1 are set. Is set in the tangential direction of the concentric circle with the screen center. Further, in order to perform highly accurate focus detection, focus detection areas ACH and A set in a tangential direction of a circle concentric with the center of the screen at a place other than the center of the screen.
Focus detection areas ACV, ARX2, ALX set in the radial direction from the center of the screen based on the lengths of LX2, ARX1
1 is set to be short.

As described above, at a position other than the center of the screen, the length of the focus detection area set in the radial direction from the center of the screen is smaller than the length of the focus detection area set in the direction tangent to the center of the screen. By setting the length to be short, it is possible to prevent the focus detection accuracy from being deteriorated as described above. In addition, since the three cross-shaped focus detection areas are efficiently set so as not to be aligned on a straight line in the screen, it is possible to reliably detect the focus of the face even when taking portrait photographs in vertical and horizontal positions. Can be. Further, it is more likely that a subject having an oblique pattern can be captured in any of the plurality of focus detection areas. Further, since the respective focus detection areas included in the three cross-shaped focus detection areas are set so as not to be parallel to each other, focus detection can be performed for a subject pattern at any angle.

FIG. 27 shows another example of setting the focus detection area. This focus detection area is set by rotating the focus detection area shown in FIG. 26 around the screen. Compared to the arrangement of the focus detection areas in FIG. 26, the projections of the three cross-shaped focus detection areas in the long side direction and the short side direction of the screen have few overlapping portions. By setting the focus detection area in this way, it is possible to efficiently capture a subject having a vertical and horizontal pattern that is statistically large in the natural world.

In the example of setting the focus detection areas shown in FIGS. 26 and 27, three cross-shaped focus detection areas are arranged at the vertices of an equilateral triangle. For example, to set the cross-shaped focus detection area in the screen in a well-balanced manner according to the aspect ratio of the screen,
It may be an isosceles triangle with two apical angles widened.

FIG. 28 shows an example of setting three or more cross focus detection areas. Focus detection area ARX11, ARX
12, ARX21, ARX22, ACH, ACV, AL
X11, ALX12, ALX21, and ALX22 each form a cross-shaped focus detection area. The focus detection areas ACH and ACV are set at the center of the screen, the focus detection areas ARX11 and ARX12 are set on the screen diagonal at the upper right part of the screen, and the focus detection areas ALX21 and ALX2 are set.
2 is set on the screen diagonal line at the lower left of the screen. further,
The focus detection areas ARX21, ARX22 are set on the screen diagonal line at the lower right of the screen, and the focus detection areas ALX11, ARX11,
ALX12 is set on the diagonal line at the upper left of the screen. The focus detection area ACH is set in the long side direction of the screen, the focus detection area ACV is set in the short side direction of the screen, the focus detection areas ARX11, ARX22, ALX12, and ALX21 are set in the radiation direction from the center of the screen. A
RX12, ARX21, ALX11, and ALX22 are set in a tangential direction of a concentric circle with the center of the screen. Further, the cross-shaped focus detection areas ARX11 and ARX12, ARX21 and A
RX22, ALX11 and ALX12, ALX21 and AL
X22 is W1 from the screen center in the screen long side direction.
It is arranged between (= WH / 4) and W2 (= WH / 6) (WH is the length in the screen long side direction).

As described above, by setting three or more cross-shaped focus detection areas on the center of the photographing screen and on both diagonal lines of the screen, no matter where the main subject is located on the screen, the main subject can be detected. Focus detection can be performed reliably. Further, since the five cross-shaped focus detection areas are efficiently set in the screen, the focus of the person's face can be detected reliably even when portrait portrait and horizontal portrait photographs are taken. Further, it is more likely that a subject having an oblique pattern can be captured in any of the plurality of focus detection areas. Since the focus detection areas included in the three cross-shaped focus detection areas out of the five cross-shaped focus detection areas are set so as not to be parallel to each other, the focus can be set on the subject pattern at any angle. Can be detected.

FIG. 29 shows another example of setting the focus detection area. Focus detection area ARH, ARV, ALH, AL
V, ACH, ACV, AUH, AUV, ADH, ADV
Form cross-shaped focus detection areas orthogonal to each other. The focus detection areas ACH and ACV are set at the center of the screen, the focus detection areas ARH and Arv are set at the right of the screen, and the focus detection areas ALH and ALV are set at the left of the screen. These focus detection areas ACH, ACV, A
RH and ARV are set on one straight line passing through the center of the screen and extending in the long side direction of the screen. The focus detection areas AUH and AUV are set at the top of the screen, and the focus detection areas ADH and ADV are set at the bottom of the screen. Cross-shaped focus detection area AUH, AU
V, ACH, ACV, ADH and ADV are set on one straight line passing through the center of the screen and in the direction of the short side of the screen. Further, the focus detection areas ACH, ARH, ALH, AUH, and ADH are set in the direction of the longer side of the screen, and the focus detection areas ACV, ARH are set.
V, ALV, AUV, and ADV are set in the short side direction of the screen. 28, the cross-shaped focus detection areas ARH, ALV, ALH, and ALV are, like the focus detection area, from W1 (= WH / 4) to W2 (= WH / 6) from the center of the screen in the long side direction of the screen. (Where,
WH is the length in the long side of the screen). Cross focus detection area A
UH, AUV, ADH, and ADV are from W1 (= WH / 4) to W2 (= WH) from the center of the screen in the short side direction of the screen.
/ 6).

As described above, by setting three or more cross-shaped focus detection areas at the center of the screen and on the vertical and horizontal center lines of the screen, no matter where the main object is located on the screen, the main object is detected. Focus detection can be performed reliably. Further, since the five cross-shaped focus detection areas are efficiently set in the screen, the focus of the person's face can be detected reliably even when portrait portrait and horizontal portrait photographs are taken. Further, it is more likely that a subject having an oblique pattern can be captured in any of the plurality of focus detection areas.

FIG. 30 shows another example of setting the focus detection area. Focus detection area ARX11, ARX12, ARX
21, ARX22, ALX11, ALX12, ALX2
1, ALX22, AUH, AUV, ADH, ADV,
Cross focus detection areas are formed orthogonal to each other. The focus detection areas ARX11, ARX12 are set on a diagonal line in the upper right part of the screen, and the focus detection areas ALX21,
ALX22 is set on the screen diagonal at the lower left of the screen, and focus detection areas ARX21 and ARX22 are set on the diagonal at the lower right of the screen. Furthermore, the focus detection area ALX
11, ALX12 is set on the diagonal line at the upper left of the screen,
The focus detection areas AUH and AUV are set at the top of the screen,
The focus detection areas ADH and ADV are set at the bottom of the screen. These cross-shaped focus detection areas AUH, AUV, A
DH and ADV are set on one straight line passing through the center of the screen in the direction of the short side of the screen. The focus detection areas AUH and ADH are set in the long side direction of the screen, and the focus detection areas AUV and ADV are set in the short side direction of the screen. Further, the focus detection area A
RX11, ARX22, ALX12, ALX21 are set in the radiation direction from the center of the screen, and the focus detection area ARX
12, ARX21, ALX11 and ALX22 are set in the tangential direction of a concentric circle with the center of the screen. Also, the cross-shaped focus detection areas ARX11, ARX12, ARX21, ARX
22, ALX11, ALX12, ALX21, ALX2
2 is W1 (= W
H / 4) to W2 (= WH / 6) (WH is the length in the long side of the screen). Furthermore, the cross-shaped focus detection areas ARX11, ARX12, ARX2
1, ARX22, ALX11, ALX12, ALX2
1, ALX22, AUH, AUV, ADH, ADV,
It is set on the circumference of the ellipse at the center of the screen, and the ratio between the major axis and the minor axis of the ellipse is set substantially equal to the aspect ratio of the screen.

As described above, by setting the cross-shaped focus detection area at the center of the screen, on both diagonal lines, and on the center line in the long side direction of the screen, even if the subject is placed at the optimum position in the photographing composition, On the other hand, the focus detection can be reliably performed. Further, since the six cross-shaped focus detection areas are efficiently set in the screen, the focus of the face position can be reliably detected even when portrait photos in vertical and horizontal positions are taken. Further, it is more likely that a subject having an oblique pattern can be captured in any of the plurality of focus detection areas. The focus detection areas included in the three cross-shaped focus detection areas out of the six cross-shaped focus detection areas are set so as not to be parallel to each other. Detection is possible.

FIG. 31 shows the configuration of another embodiment of the focus detection optical system according to the present invention. The same elements as those in the focus detection optical system shown in FIG. Focus detection areas ARX1, ARX2, AC formed by the respective openings of the field mask MSK.
H, ACV, ALX1, and ALX2 each form a cross-shaped focus detection area. Focus detection area ACH
Is set at the center of the screen in the long side direction of the screen, and the focus detection area ACV is set at the center of the screen in the short side direction of the screen.
Are focus detection areas ACH and A, respectively, which are distant from the center of the screen to the left and right in the long side of the screen and up and down in the short side of the screen.
It is set at an angle of 45 ° to CV.

When the focus detection optical system shown in FIG. 1 is applied as it is to the focus detection area set as described above,
Behind each focus detection area, a condenser lens, an aperture mask, a separator lens, and a sensor are arranged, and focus detection areas ALX1, ALX2, ARX1, ARX on the left and right of the screen.
The light-receiving sections of the sensor SNS corresponding to 2 must be displaced in the same direction in accordance with the displacement of these focus detection areas in the vertical direction on the screen short side. Therefore, the sensor SNS
Above, the light receiving units PCH1, PCH2, PCV of the sensor SNS corresponding to the focus detection areas ACH, ACV at the center of the screen
1, PCV2 and the left and right focus detection areas ALX1,
Sensor SNS corresponding to ALX2, ARX1, ARX2
Light receiving sections PLX11, PLX12, PLX21, PLX
22, PRX11, PRX12, PRX21, PRX2
Since 2 is not arranged in a straight line, a large sensor chip is required and the cost is increased.

Therefore, as shown in FIG. 31, focus detection areas ALX1, ALX2, ARX1, ARX on the left and right of the screen.
The optical axes of the condenser lenses FR and FL corresponding to 2 above and below the center of each focus detection area (the intersection of each center line of ARX1 and ARX2 and the intersection of each center line of ALX1 and ALX2) in the direction of the short side of the screen. The optical axis of the focus detection optical system on the left and right of the screen is deflected. As a result, the secondary subject images corresponding to the focus detection areas ALX1, ALX2, ARX1, ARX2 on the left and right of the screen are shifted to the focus detection area AC in the center of the screen.
It becomes aligned with the secondary subject image corresponding to H and ACV. Therefore, on the sensor SNS, the light receiving sections PRX11 and PRX1 corresponding to the focus detection areas on the left and right of the screen.
2, PRX21, PRX22, PLX11, PLX1
2. PLX21, PLX22 are light receiving units PCH1, PCH2, PCV1, light receiving units corresponding to the focus detection area at the center of the screen.
It can be arranged in line with PCV2. The aperture openings and the separator lenses corresponding to the focus detection areas on the left and right sides of the screen are also displaced up and down in the direction of the short side of the screen on the respective optical axes deflected by the condenser lenses FL and FR.

By configuring the focus detection optical system in this manner, even if three cross-shaped focus detection areas are set so as not to be aligned on a straight line, the light-receiving portion corresponding to each cross-shaped focus detection area will have a sensor SNS. Because it can be arranged in a straight line above, the sensor chip can be made compact,
Reduce costs.

In the configuration of the above embodiment, the condenser lenses FC, FL, FR, the field mask MSK, the aperture mask RX, and the separator lenses SCH1, SCH2, S
LH1, SLH2, SRH1, SRH2, SLV1, S
LV2, SRX11, SRX12, SRX21, SRX
22, SCV1, SCV2, SLX11, SLX12,
SLX21 and SLX22 serve as the focus detection optical system and the sensor S
NS constitutes each photoelectric conversion unit.

[0106]

As described above, according to the first aspect of the present invention, a plurality of focus detection areas are set at the center of the shooting screen and at a place other than the center, and the focus detection areas set at the center of the shooting screen are set. And the pixel pitch and / or pixel width of the pair of light receiving units corresponding to the focus detection area set at a position other than the center of the photographing screen are relative to each other. In this way, it is possible to compensate for the decrease in optical performance at places other than the center of the screen due to the asymmetricity of the focus detection optical system. Can be maintained to the same extent. Further, according to the invention of claim 2, the pixel pitch of the pair of light receiving sections corresponding to the focus detection area set at a place other than the center of the photographing screen,
Since the pixel pitch is set finer than the pixel pitch of the pair of light receiving sections corresponding to the focus detection area set at the center of the photographing screen, the same effect as in the first aspect can be obtained. Further, according to the third aspect of the present invention, the pixel width of the pair of light receiving sections corresponding to the focus detection area set at a place other than the center of the shooting screen corresponds to the focus detection area set at the center of the shooting screen. Since the width is set to be wider than the pixel width of the pair of light receiving sections, the same effect as that of the first aspect can be obtained.

According to the fourth aspect of the present invention, a cross-shaped focus detection area is set at a place other than the center of the photographing screen, and one of the cross-shaped focus detection areas is defined by radiation from the center of the photographing screen. Since the length of the band-shaped focus detection area set on the radiation is set shorter than the length of the band-shaped focus detection area orthogonal to the band-shaped focus detection area, the distortion of the focus detection optical system is set. Can be compensated for, and accurate focus detection can be performed in a cross-shaped focus detection area other than the center of the screen.

According to the fifth aspect of the invention, a cross-shaped focus detection area is set at a place other than the center of the photographing screen, and one of the cross-shaped focus detection areas of the cross-shaped focus detection area is defined as a radiation from the center of the photographing screen. A pixel pitch and / or a pixel width of a pair of light receiving portions corresponding to the band-shaped focus detection region set on the radiation and a pair corresponding to the band-shaped focus detection region orthogonal to the band-shaped focus detection region. Since the pixel pitch and / or the pixel width of the light receiving unit are set to be relatively different from each other, it is possible to compensate for a decrease in optical performance due to the asymmetricity of the focus detection optical system, and to reduce radiation from the center of the screen. The focus detection accuracy in the band-shaped focus detection areas set above can be maintained at the same level as the accuracy of the focus detection areas orthogonal to them. According to the invention of claim 6, the pixel pitch of the light receiving unit corresponding to the band-shaped focus detection area set on the radiation from the center of the imaging screen corresponds to the band-shaped focus detection area orthogonal to the band-shaped focus detection area. Since the pixel pitch is set finer than the pixel pitch of the light receiving section, the same effect as that of the fifth aspect can be obtained. Furthermore, according to the invention of claim 7, the pixel width of the light receiving section corresponding to the band-shaped focus detection area set on the radiation from the center of the imaging screen corresponds to the band-shaped focus detection area orthogonal to the band-shaped focus detection area. Since the width is set to be wider than the pixel width of the light receiving section, the same effect as that of the fifth aspect can be obtained.

According to the invention of claim 8, a focus detection area is set on the radiation from the center of the imaging screen, and the pixel pitch and / or the pixel pitch of one of the pair of light receiving sections corresponding to the focus detection area are set. Alternatively, since the pixel width and the pixel pitch and / or the pixel width of the other light receiving unit are set to be relatively different from each other, it is possible to compensate for a decrease in optical performance due to the asymmetry of the focus detection optical system. Further, it is possible to improve the focus detection accuracy in the focus detection area on the radiation from the center of the screen.

According to the ninth aspect of the present invention, a focus detection area is set on the radiation from the center of the imaging screen at a place other than the center of the imaging screen, and each of the pair of light receiving sections corresponding to the focus detection area is set. Since the pixel pitch is set so that the distortion of the secondary subject image re-imaged by the focus detection optical system is corrected, it is possible to compensate for a decrease in the focus detection accuracy due to the distortion of the focus detection optical system. , Accurate focus detection can be performed at a place other than the center of the image.

According to the tenth aspect of the present invention, a plurality of band-shaped focus detection areas are set at the center of the photographing screen and at places other than the center, and pixels of each light receiving section corresponding to each band- shaped focus detection area are set.
The light receiving section is inclined and aligned with the direction perpendicular to the longitudinal direction.
Base, a pair of light receiving corresponding to the pair of the tilt-out direction of the pixel of the light receiving portion, band-like focus detection areas set in a location other than the center of the shooting screen corresponding to the band-shaped focus detection area set in the center of the shooting screen Since the inclination directions of the pixels in the section are set to be relatively different from each other, it is possible to compensate for a decrease in optical performance due to the asymmetricity of the focus detection optical system, and to improve the focus detection accuracy at a place other than the center of the screen. The accuracy can be maintained at the same level as the accuracy at the center of the screen.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of an embodiment of a focus detection optical system according to the present invention.

2A is a diagram illustrating an arrangement of a focus detection area of the focus detection optical system illustrated in FIG. 1, and FIG. 2B is a diagram illustrating a relationship between the focus detection area and a subject edge in an oblique pattern. is there.

FIG. 3 is a diagram illustrating another example of setting a cross-shaped focus detection area.

FIG. 4 is a diagram showing a relationship between the arrangement of light receiving units on a sensor corresponding to each focus detection area shown in FIG. 3 and a secondary subject image.

FIG. 5 is a diagram illustrating another example of setting a cross-shaped focus detection area.

FIG. 6 is a diagram showing another example of setting the cross-shaped focus detection area.

FIG. 7 is a diagram illustrating another example of setting the cross-shaped focus detection area.

8 is a diagram showing a relationship between the arrangement of light receiving units on a sensor corresponding to each focus detection area shown in FIG. 7 and a secondary subject image.

FIG. 9 is a diagram showing details of a light receiving unit on the sensor shown in FIG. 8;

FIG. 10 is a diagram showing an example in which some light receiving units on the sensor shown in FIG. 8 are set so as to correct distortion of a focus detection optical system.

FIG. 11 shows each pixel of each light receiving unit on the sensor shown in FIG.
FIG. 9 is a diagram illustrating an example of setting with an inclination.

FIG. 12 is a diagram showing an example of setting a focus detection area of another shape.

FIG. 13 is a diagram showing a relationship between the arrangement of light receiving units on a sensor corresponding to the focus detection area shown in FIG. 12 and a secondary subject image.

FIG. 14 is a diagram showing an example of setting a focus detection area of another shape.

FIG. 15 is a diagram showing a relationship between the arrangement of light receiving units on a sensor corresponding to the focus detection area shown in FIG. 14 and a secondary subject image.

FIG. 16 is a diagram showing another example of setting the cross-shaped focus detection area.

FIG. 17 is a diagram illustrating another setting example of the cross-shaped focus detection area.

FIG. 18 is a diagram illustrating another example of setting the cross-shaped focus detection area.

19 is a diagram showing a modification of the cross-shaped focus detection area shown in FIG.

20 is a diagram showing the relationship between the arrangement of the light receiving units on the sensor corresponding to the cross-shaped focus detection area shown in FIG. 19 and the secondary subject image.

21A is a diagram illustrating another example of setting of the three cross-shaped focus detection areas, and FIG. 21B is a diagram illustrating the three focus detection areas illustrated in FIG. FIG.

FIG. 22 is a diagram showing a relationship between the three cross-shaped focus detection areas shown in FIG. 21A when the camera is held in a vertical position and a human image during portrait shooting.

23A is a diagram illustrating an example of photographing a subject having a vertical and horizontal pattern in the three cross-shaped focus detection areas illustrated in FIG. 21A, and FIG. 23B is a diagram illustrating the example illustrated in FIG. FIG. 9 is a diagram illustrating an example in which a subject having an oblique pattern is photographed in three cross-shaped focus detection areas.

FIG. 24 is a diagram illustrating another example of setting three cross-shaped focus detection areas.

FIG. 25 is a diagram illustrating another example of setting three cross-shaped focus detection areas.

FIG. 26 is a diagram illustrating another example of setting three cross-shaped focus detection areas.

FIG. 27 is a diagram showing a modification of the three cross-shaped focus detection areas shown in FIG. 26;

FIG. 28 is a diagram illustrating a setting example of five cross-shaped focus detection areas.

FIG. 29 is a diagram showing another example of setting five cross-shaped focus detection areas.

FIG. 30 is a diagram illustrating an example of setting six cross-shaped focus detection areas.

FIG. 31 is a diagram showing a configuration of another embodiment of the focus detection optical system according to the present invention.

32A and 32B are diagrams illustrating a conventional setting example of three cross-shaped focus detection areas, in which FIG. 32A illustrates an example in which a straight line is set in the long side direction of the screen, and FIG. An example of setting on a straight line is shown.

FIG. 33 (a) is a diagram showing an example in which three cross-shaped focus detection areas set on one straight line in the long-side direction of the screen shown in FIG.
FIG. 33B is a diagram illustrating an example of supplementing a subject having an oblique pattern with three cross-shaped focus detection areas set on one straight line in the diagonal direction of the screen illustrated in FIG.

34A is a diagram illustrating an example in which portrait shooting is performed in three cross-shaped focus detection areas set on one straight line in the long-side direction of the screen illustrated in FIG. 32A; FIG. )
FIG. 33 is a diagram showing an example in which portrait photography is performed in three cross-shaped focus detection areas set on one straight line in the diagonal direction of the screen shown in FIG.

FIG. 35 (a) is a diagram showing an example of supplementing a subject in a vertical and horizontal pattern with three cross-shaped focus detection areas set on one straight line in the long side direction of the screen shown in FIG. 32 (a);
FIG. 33B is a diagram illustrating an example of supplementing a subject having an oblique pattern with three cross-shaped focus detection areas set on one straight line in the diagonal direction of the screen illustrated in FIG.

FIG. 36 is a diagram showing a conventional example in which three band-shaped focus detection areas are set to be linear in the direction of the long side of the screen.

FIG. 37 is a diagram showing a focus detection optical system in which the focus detection area shown in FIG. 36 is set.

FIG. 38: A primary image of a subject formed in a focus detection area at the center of the screen shown in FIG. 36 is re-formed as a pair of secondary subject images on a photoelectric conversion sensor by a focus detection optical system shown in FIG. 6A and 6B are diagrams showing the image height and distortion when the secondary subject image is re-imaged by one of the pair of separator lenses, and FIG. And (c) show the difference between the pair of distortions shown in (a) and (b).

39. A primary image of a subject formed in a focus detection area other than the center of the screen shown in FIG. 36 is formed as a pair of secondary subject images on a photoelectric conversion sensor by a focus detection optical system shown in FIG. FIG. 8A is a diagram illustrating an image height and distortion when re-imaging is performed. FIG. 9A illustrates an image height and distortion of a secondary subject image re-imaged by one of a pair of separator lenses, and FIG. ) Shows the image height and distortion of the secondary subject image re-imaged by the other separator lens, and (c) shows the difference between the pair of distortions shown in (a) and (b).

FIG. 40 is a diagram showing an example in which a focus detection area is set at the center of the shooting screen in the direction of the longer side of the screen, and a focus detection area is set at the left and right sides of the focus detection area in a tangential direction of a concentric circle with the center of the screen.

FIG. 41 is a diagram showing a configuration of a focus detection device in which three cross-shaped focus detection areas are set on one straight line in the long side direction of the screen at the center and at a place other than the center of the screen.

FIG. 42 is a diagram showing a substantial pupil aperture shape when viewing the lens side from a focus detection area set at a place other than the center of the screen.

[Explanation of symbols]

ACH, ACV, ALH, ALV, ARH, ARV, A
RX1, ARX2, ARX11, ARX12, ARX2
1, ARX22, ALX1, ALX2, ALX11, A
LX12, ALX21, ALX22, ACX1, ACX
2, ALH1, ALH2, ARH1, ARH2, AU
H, AUV, ADH, ADV Focus detection area AX Optical axis of photographing optical system EH1, EH2, EV1, EV2, EX11, EX1
2, EX21, EX22 Pupil area EX Pupil diameter EXT Exit pupil plane FC, FL, FR Condenser lens MSK Field mask P Photographing screen PCH1, PCH2, PCV1, PCV2, PCX1
1, PCX12, PCX21, PCX22, PRX1
1, PRX12, PRX21, PRX22, PRH1,
PRH2, PRV1, PRH11, PRH12, PRH
21, PRH22, PRV2, PLX11, PLX1
2, PLX21, PLX22, PLH1, PLH2, P
LH11, PLH12, PLH21, PLH22, PL
V1, PLV2 Light receiving unit RX Aperture mask RLH1, RLH2, RLV1, RLV2, RRX1
1, RRX12, RRX21, RRX22, RCH1,
RCH2, RCV1, RCV2, RLX11, RLX1
2, RLX21, RLX22 Aperture mask opening SCH1, SCH2, SLH1, SLH2, SRH1,
SRH2, SLV1, SLV2, SRX11, SRX1
2, SRX21, SRX22, SCV1, SCV2, S
LX11, SLX12, SLX21, SLX22 Separator lens SNS photoelectric conversion sensor

──────────────────────────────────────────────────続 き Continued on the front page (58) Fields surveyed (Int. Cl. ⁷ , DB name) G02B ^7/ 28-7/40 G03B 3/00-3/12

Claims (10)

(57) [Claims] 1. A focus detection optical system for guiding a light beam passing through a plurality of focus detection areas set in a photographing screen onto a photoelectric conversion means to be described later, and a pair of light receiving sections comprising a plurality of pixels are provided in each of the focus detection areas. A plurality of pairs corresponding to the above, and a photoelectric conversion means for receiving a light beam having passed through each of the focus detection areas, and a focus adjustment of a photographing optical system for each of the focus detection areas based on an output signal of the photoelectric conversion means. A plurality of focus detection areas set at positions other than the center and the center of the shooting screen, and the focus set at the center of the shooting screen. The pixel pitch and / or pixel width of the pair of light receiving units corresponding to the detection area, and the pixel pitch and / or image of the pair of light receiving units corresponding to the focus detection area set at a position other than the center of the photographing screen. Focus detection device, wherein a width is set to a relatively different. 2. The focus detecting device according to claim 1, wherein
The pixel pitch of the pair of light receiving sections corresponding to the focus detection area set at a place other than the center of the shooting screen is a pixel of the pair of light receiving sections corresponding to the focus detection area set at the center of the shooting screen. A focus detection device characterized by being set finer than the pitch. 3. The focus detecting device according to claim 1, wherein
The pixel width of the pair of light receiving sections corresponding to the focus detection area set at a place other than the center of the shooting screen is a pixel of the pair of light receiving sections corresponding to the focus detection area set at the center of the shooting screen. A focus detection device characterized by being set wider than the width. 4. A photoelectric conversion means for receiving, via a focus detection optical system, a light beam passing through a cross-shaped focus detection area in which two band-shaped focus detection areas are set to be orthogonal to each other in a photographing screen; A focus detection operation unit that detects a focus adjustment state of the imaging optical system for each of the band-shaped focus detection regions based on an output signal of the photoelectric conversion unit, wherein the cross-shaped focus detection region includes: The zonal focus detection area is set at a position other than the center of the imaging screen, and one of the cruciform focus detection areas is set on the radiation from the center of the imaging screen, and the zonal focus set on the radiation is set. A focus detection device, wherein a length of the detection area is set shorter than a length of the strip-shaped focus detection area orthogonal to the strip-shaped focus detection area. 5. A focus detection optical system which guides a light beam passing through a cross-shaped focus detection area in which two band-shaped focus detection areas are set so as to be orthogonal to each other in a photographing screen, to a later-described photoelectric conversion means; A plurality of pairs of light receiving sections each including a plurality of pixels corresponding to the respective band-shaped focus detection areas, photoelectric conversion means for receiving a light beam passing through each of the band-shaped focus detection areas, and an output signal of the photoelectric conversion means. And a focus detection calculating means for detecting a focus adjustment state of the photographing optical system for each of the band-shaped focus detection areas on the basis of the cross-shaped focus detection area. One of the cross-shaped focus detection areas is set on the radiation from the center of the imaging screen, and a pair of receivers corresponding to the band-shaped focus detection area set on the radiation. The pixel pitch and / or the pixel width of the pair of light receiving units corresponding to the band-shaped focus detection region orthogonal to the band-shaped focus detection region are set to be relatively different from each other. A focus detection device. 6. The focus detection device according to claim 5, wherein
The pixel pitch of the light receiving section corresponding to the band-shaped focus detection area set on the radiation from the center of the imaging screen is greater than the pixel pitch of the light receiving section corresponding to the band-shaped focus detection area orthogonal to the band-shaped focus detection area. A focus detection device, wherein the focus detection device is also set in detail. 7. The focus detecting device according to claim 5, wherein
The pixel width of the light receiving unit corresponding to the band-shaped focus detection region set on the radiation from the center of the imaging screen is greater than the pixel width of the light receiving unit corresponding to the band-shaped focus detection region orthogonal to the band-shaped focus detection region. The focus detection device is also set to be wide. 8. A focus detection optical system for guiding a light beam that has passed through a focus detection area set in a photographing screen onto a photoelectric conversion means, which will be described later, and a pair of light receiving units including a plurality of pixels. A focus detection device comprising: a photoelectric conversion unit that receives a light beam; and a focus detection calculation unit that detects a focus adjustment state of an imaging optical system in the focus detection area based on an output signal of the photoelectric conversion unit. The detection area is set on radiation from the center of the imaging screen,
The pixel pitch and / or pixel width of one of the pair of light receiving units corresponding to the focus detection area is set to be relatively different from the pixel pitch and / or the pixel width of the other light receiving unit. A focus detection device. 9. A focus detection optical system for forming a secondary subject image by re-forming a subject image in a focus detection area set in a photographing screen on a photoelectric conversion means to be described later, and a pair of a plurality of pixels. A photoelectric conversion unit that receives a light beam that has passed through the focus detection area at a light receiving unit, and a focus detection calculation unit that detects a focus adjustment state of an imaging optical system in the focus detection area based on an output signal of the photoelectric conversion unit. In the focus detection device provided with, the focus detection area is set on radiation from the center of the imaging screen at a location other than the center of the imaging screen, and each of the pair of light receiving units corresponding to the focus detection area Wherein the pixel pitch is set such that distortion of the secondary subject image re-imaged by the focus detection optical system is corrected. 10. A focus detecting optical system for guiding on later photoelectric conversion means a light beam having passed through the plurality of strip-like focus detection areas set in the photographing screen, the respective strip-like focus a pair of light receiving portions comprising a plurality of pixels a plurality of pairs in response to the detection region, wherein the photoelectric conversion means for receiving the light flux that has passed through the band-shaped focus detection region, based on the output signal of the photoelectric conversion means, wherein the respective strip-like focus <br/> out inspections a focus detecting apparatus having a focus detection calculation means for detecting a focusing state of the photographic optical system for each area, the plurality of strip-shaped focus detection area is set at a location other than the center and the center of the front Symbol shooting screen, the Each band focus detection area
The pixel of each light receiving section corresponding to is perpendicular to the longitudinal direction of each light receiving section
Such is arranged to be inclined with respect to the direction, the inclination-out direction of the pixel of the pair of light receiving portions corresponding to the strip-shaped focus detection area set in the center of the shooting screen, non-central location of the imaging screen Wherein the inclination directions of the pixels of the pair of light receiving units corresponding to the band-shaped focus detection areas set in the above are set to be relatively different from each other.