JP2006171120A - Photographic apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a photographic apparatus capable of suppressing a light beam of relatively small wavelength band from affecting another photographing, and capable of effectively using the light beam. <P>SOLUTION: In the detection of the contrast of an object, when it is decided that an object distance measured by an external AF part is shorter than a prescribed distance, the light beam is emitted from an LED as a 1st auxiliary light beam emitter; whereas when the object distance is longer than the prescribed distance, the light beam is emitted from an LD as a 2nd auxiliary light beam emitter. In the case of photographing the objects at a close distance shorter than the prescribed distance all at once, color laser beam is suppressed from affecting another photographing; and in the case of photographing a distant view, the laser beam is effectively used as the AF auxiliary light beam. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a photographing apparatus that includes an image sensor and generates an image signal by forming a subject image on the image sensor.

  In recent years, there are many photographing apparatuses having a so-called autofocus (hereinafter referred to as AF) function that automatically performs focus adjustment. Some photographing apparatuses having the AF function perform so-called TTL (Thru The Lens) distance measurement, in which focus adjustment is performed through a photographing lens. In the TTL distance measurement, a subject image is formed on an image pickup device by a photographing optical system including an optical member for focus adjustment, an adjustment image signal is generated prior to photographing, and based on the adjustment image signal. Focus adjustment is performed.

  When performing this TTL distance measurement, if the brightness of the subject is dark, the contrast between the subject and the background cannot be detected well and accurate distance measurement cannot be performed. In some cases, auxiliary light is emitted toward a subject to obtain subject contrast to perform accurate distance measurement (see, for example, Patent Document 1). In this case, an LED that can be driven with low power is often used. This LED has many colored objects, but can also be white. However, since the LED has a small amount of light emission and the irradiation pattern is often widened, there is a problem that the auxiliary light cannot reach a subject far away.

  Therefore, although the wavelength band is relatively narrow, it becomes colored light, but laser light that can make the light reach even when the subject is at a long distance and that can project a predetermined pattern using a hologram The auxiliary light used is considered (for example, refer to Patent Document 2).

However, if a predetermined pattern of laser light is fixedly used as AF auxiliary light, the laser light of the predetermined pattern may be received by other photographers when everyone is shooting a short-distance subject all at once. There is a case where a laser pattern is clearly reflected in a photograph taken by another photographer by being irradiated as AF auxiliary light within an angle of view to be photographed.
JP 2002-139664 A JP 2002-237990 A

  In view of the above circumstances, an object of the present invention is to provide an imaging apparatus that can effectively use light having a relatively narrow wavelength band while suppressing the influence on other imaging. .

The first photographing apparatus of the present invention that achieves the above object forms a subject image on an image pickup element by a photographing optical system including an optical member for focus adjustment, and repeatedly generates an image signal for adjustment prior to photographing. In the photographing apparatus that detects the subject contrast based on the image signal for adjustment and performs focus adjustment, and generates and records the image signal for recording according to the photographing operation.
An external AF unit that has a distance sensor separate from the image sensor and measures the distance to the subject using the distance sensor;
A first auxiliary light emitter for irradiating light with a relatively wide wavelength band toward the subject for subject contrast detection;
A second auxiliary light emitter that emits light with a relatively narrow wavelength band toward the subject for subject contrast detection;
When detecting the subject contrast, the first auxiliary light emitter is caused to emit light when the distance is shorter than a predetermined distance according to the subject distance measured by the external AF unit, and the distance is longer than the predetermined distance. And a light emission control unit that emits second auxiliary light.

  According to the first photographing apparatus, auxiliary light is emitted from the first auxiliary light emitter when everyone is simultaneously photographing a short distance object. The auxiliary light emitted from the first auxiliary light emitter is a light having a relatively wide wavelength band and is almost white light. Therefore, the first light emitter is used where another person takes a picture. Even if the AF auxiliary light is irradiated from the other, it does not affect the photographing of other photographers. As the first light emitter, a white LED, a white lamp, or the like is typically used to emit light having a relatively wide wavelength band.

  Also, when the subject is on the far side of the predetermined distance, for example, when shooting a distant view, it is assumed that there is an extremely low possibility that the angle of view of the other photographer and the angle of view of the photographer will overlap. In particular, even if the light has a narrow wavelength band and is colored, AF auxiliary light reaching a distant subject is emitted from the second auxiliary light emitter toward the subject. Such a second auxiliary light emitter includes a laser diode.

  In this way, both the light emitted from the first auxiliary light emitter and the light emitted from the second auxiliary light emitter are effectively utilized according to the shooting scene.

  As described above, it is possible to realize an imaging apparatus capable of effectively using light having a relatively narrow wavelength band while suppressing the influence on other imaging.

The second photographing apparatus of the present invention that achieves the above object forms a subject image on an image pickup device by a photographing optical system including an optical member for focus adjustment, and repeatedly generates an adjustment image signal prior to photographing. In the photographing apparatus that detects the subject contrast based on the image signal for adjustment and performs focus adjustment, and generates and records the image signal for recording according to the photographing operation.
A photometric unit for detecting the field luminance;
A first auxiliary light emitter for irradiating light with a relatively wide wavelength band toward the subject for subject contrast detection;
A second auxiliary light emitter that emits light with a relatively narrow wavelength band toward the subject for subject contrast detection;
In detecting the subject contrast, the first auxiliary light emitter is caused to emit light when the luminance is higher than a predetermined luminance according to the luminance of the subject measured by the photometry unit, and the luminance is lower than the predetermined luminance. And a light emission control unit that emits light from the second auxiliary light emitter.

  According to the second photographing apparatus of the present invention, when the subject brightness measured by the photometry unit is higher than a predetermined brightness, the light emission control unit causes the first auxiliary light emitter, for example, relative The AF auxiliary light is emitted toward the subject from the LED having low emission power.

  As a case where the subject brightness is higher than the predetermined brightness, there may be a shooting scene where shooting is performed in a room that is relatively bright during the day. In such a photographic scene, everyone may take a commemorative photo at the same time. Therefore, AF auxiliary light is emitted from the first auxiliary light emitter, for example, an LED, toward the subject. Then, even if everyone is taking a commemorative photo at the same time, even if the second photo taking device is used, it does not affect other people's photo taking.

  Further, when it is considered that the first auxiliary light emitter does not have sufficient light quantity, focus adjustment cannot be performed even if light is emitted from the first auxiliary light emitter. Therefore, for example, when shooting a night scene, which is one of the cases where the brightness is lower than the predetermined brightness, the AF is switched to the second auxiliary light emitter with less attenuation of the light amount due to the distance than the first light emitter. If the auxiliary light is irradiated, high-precision focus adjustment can be performed even when the subject brightness is low.

  In this way, it is possible to realize an imaging apparatus capable of effectively using light having a relatively narrow wavelength band while suppressing the influence on other imaging.

The third photographing apparatus of the present invention that achieves the above object forms a subject image on an image pickup element by a photographing optical system including an optical member for focus adjustment, and repeatedly generates an image signal for adjustment prior to photographing. In the photographing apparatus that detects the subject contrast based on the image signal for adjustment and performs focus adjustment, and generates and records the image signal for recording according to the photographing operation.
A first auxiliary light emitter for irradiating light with a relatively wide wavelength band toward the subject for subject contrast detection;
A second auxiliary light emitter that emits light with a relatively narrow wavelength band toward the subject for subject contrast detection;
A user operator for switching between irradiation by the first auxiliary light emitter and irradiation by the second auxiliary light emitter;
In detecting the object contrast, a light emission control unit that emits light from the first auxiliary light emitter or the second auxiliary light emitter is provided according to the switching state by the user operation.

  According to the third photographing apparatus of the present invention, the light emission control unit causes the first auxiliary light emitter or the second auxiliary light emitter to emit light according to a switching state by the user operator. Therefore, the user can perform shooting after selectively switching freely according to the shooting scene. If another photographer is taking a commemorative photo or the like, and the laser light emitted from the second auxiliary light emitter such as a laser diode is used, the laser light is likely to enter the angle of view of the other photographer. In this case, the user can select, for example, an LED that is the first auxiliary light emitter, and cause the LED to emit LED light, so that the photographing of other photographers is not affected. .

  Even in this way, it is possible to realize an imaging apparatus capable of effectively using light having a relatively narrow wavelength band while suppressing the influence on other imaging.

A fourth imaging apparatus that achieves the above object forms a subject image on an imaging element by an imaging optical system including an optical member for focus adjustment, repeatedly generates an adjustment image signal prior to imaging, and performs the adjustment. In an imaging device that detects a subject contrast based on an image signal for use and performs focus adjustment, and generates and records an image signal for recording according to an imaging operation.
A first auxiliary light emitter for irradiating light with a relatively wide wavelength band toward the subject for subject contrast detection;
A second auxiliary light emitter that emits light with a relatively narrow wavelength band toward the subject for subject contrast detection;
A user operator for switching between a normal AF mode with a relatively long shutter time for generating the adjustment image signal and a high-speed AF mode with a relatively short shutter time;
When the subject contrast is detected, when the normal AF mode is switched according to the switching state by the user operator, the first auxiliary light emitter is caused to emit light and the high AF mode is switched. And a light emission control unit that emits light from the second auxiliary light emitter.

  According to the fourth imaging apparatus, when the normal mode and the high-speed AF mode are switched to the normal mode side by the user operator, the wavelength band from the first auxiliary light emitter is wide. When white light is emitted toward the subject as AF auxiliary light and switched to the high-speed AF mode, a laser that reaches the distance from the second auxiliary light emitter, for example, a laser diode, although it is colored light Light is emitted toward the subject as AF auxiliary light.

  In this way, switching between the normal mode and the high-speed mode can be freely performed by the user operator. If another photographer is taking a commemorative photo and using a colored laser beam, the other photo is taken. If the colored laser beam is likely to enter the person's angle of view, the user can take a picture after selecting the normal mode.

  The difference between the normal mode and the high-speed AF mode is a difference in charge accumulation time of the image pickup element such as a CCD during AF. In the high-speed AF mode, the charge accumulation time is shorter than that in the normal mode. At this time, since the amount of light received by the CCD is reduced by shortening the charge accumulation time, the second light emitter such as a laser diode is selected instead of the first light emitter such as LED.

  In this way, it is possible to realize an imaging apparatus capable of effectively using light having a relatively narrow wavelength band while suppressing the influence on other imaging.

  The above first to fourth imaging devices are collectively expressed as follows.

That is, in a photographing device that detects the subject contrast and adjusts the focus prior to the photographing operation,
A first auxiliary light emitter for irradiating light with a relatively wide wavelength band toward the subject for subject contrast detection;
A second auxiliary light emitter that emits light with a relatively narrow wavelength band toward the subject for subject contrast detection;
A switching means for switching between the first auxiliary light emitter and the second auxiliary light emitter is provided.

   As described above, it is possible to realize an imaging apparatus that can effectively use light having a relatively narrow wavelength band while suppressing the influence on other imaging.

  Hereinafter, embodiments of the present invention will be described.

  FIG. 1 is a diagram showing a digital camera which is an embodiment of a photographing apparatus of the present invention.

  FIG. 1 is a configuration perspective view of a digital camera according to an embodiment of the present invention.

  A digital camera 100 shown in FIG. 1 forms a subject image on an image pickup device by a photographing optical system including a focus adjustment optical member, for example, a focus lens, and repeatedly generates an adjustment image signal prior to photographing. A subject contrast is detected on the basis of the image signal for use and focus adjustment is performed (hereinafter referred to as TTL distance measurement), and an image signal for recording is generated and recorded in accordance with the photographing operation.

  As shown in FIG. 1, a lens barrel is provided in the center of the camera body of the digital camera 100 of the present embodiment. A photographing optical system including the focus lens is built in the lens barrel 170, and an image of a subject is guided through the photographing optical system to a CCD solid-state imaging device (hereinafter referred to as a CCD) provided in the digital camera 100. It is like that. Further, above the lens barrel 170, a flashlight emission window in which the protector 160 is fitted in the viewfinder 105 and the window frame is provided.

  In the digital camera 1, an image signal representing a through image or a captured image is generated by the CCD inside the digital camera 1, and the above-described TTL distance measurement and further TTL photometry are performed based on the image signal obtained by the CCD. Thus, the subject distance and the subject brightness are detected.

  Since the release button 102 on the upper surface of the camera body of the digital camera 100 according to the present embodiment has two operation modes of half-pressing and full-pressing, the TTL distance measurement is performed at the time of half-pressing, and the in-focus position is determined. After the detection, the focus lens is placed at the in-focus position, TTL photometry is performed to adjust the aperture of the aperture 1112, and then the CCD is exposed in response to the full-press operation.

  Further, in the digital camera 100 of the present embodiment, a distance measuring sensor separate from the CCD for performing rough distance measurement so that TTL distance measurement can be completed in as short a time as possible is provided inside. Has been deployed. Two distance measuring windows 141 and 142 for guiding subject light to the distance measuring sensor are provided on both sides of the viewfinder 105. Further, a laser window 180 for irradiating the subject with laser light emitted from the LD as AF auxiliary light is provided outside one distance measuring window 141, and the AF window is provided outside the other distance measuring window 142. An LED window 190 is provided to irradiate the subject with light emitted from the LED as auxiliary light.

  FIG. 2 is a block diagram showing the configuration of a signal processing unit provided in the digital camera 100 of FIG.

  The configuration of the signal processing unit in the digital camera 100 will be described with reference to FIG.

  FIG. 2 is a configuration block diagram of a signal processing unit provided in the digital camera 100.

  In the digital camera 100 of this embodiment, all processes are controlled by the main CPU 110, and operation signals from the various switch groups 101 of the operation unit shown in FIG. 1B are supplied to the input unit of the main CPU 110, respectively. Has been. The main CPU 110 has an EEPROM 110a, and a program necessary for operating as the digital camera 100 is written in the EEPROM 110a. When the power switch 101a of the digital camera having such a configuration is turned on, the operation of the entire digital camera is controlled by the CPU 110 according to the procedure of the program in the EEPROM 110a.

  First, the flow of an image signal will be described with reference to FIG.

  When the power switch 101a (see FIG. 1) in the switch group 101 is turned on, it is detected by the main CPU 110 that the power switch 101a has been turned on, and power is supplied from the power supply 130 to each block such as the main CPU 110 and the photometric distance measuring CPU 120. Is supplied. When the mode lever 101e in the switch group 101 is switched to the photographing side when the power supply 130 is turned on, the subject image formed on the CCD 110 is first thinned out at predetermined intervals as an image signal. The subject image based on the output image signal is displayed on the LCD panel 150 of the image display LCD. A timing signal is supplied to the CCD 112 from a clock generator (hereinafter referred to as CG) 1121, and image signals are thinned out at predetermined intervals by the timing signal and output. The CG 1121 outputs a timing signal based on an instruction from the CPU 110, and the timing signal is supplied to the A / D unit 113 and the white balance adjustment / γ processing unit 114 in the subsequent stage in addition to the CCD 112. . Accordingly, the CCD 112, the A / D unit 113, and the white balance / γ processing unit 114 perform processing of image signals in order in synchronization with the timing signal.

  As described above, the A / D unit 113 converts the digital signal into a digital image signal in synchronization with the timing signal output from the CG 1121 in accordance with the instruction from the CPU 110, and the white balance γ processing unit 114 performs predetermined white balance adjustment and γ correction. Therefore, it is necessary to adjust the flow of the image signals well. Therefore, a buffer memory 115 is provided in the subsequent stage, and the YC processing unit sends the image signals at predetermined intervals by the buffer memory 115. The timing of transferring to 116 is adjusted. From the buffer memory 115, the image signal stored at the old time is transferred to the YC processing unit 116 first. The image signal transferred to the YC processing unit 116 is converted from the RGB signal to the YC signal by the YC processing unit 116, and then the converted YC signal is supplied to the image display LCD 15 side via the bus 121. The YC → RGB converter 151 for converting the YC signal into the RGB signal is provided in the front stage of the image display LCD 15. The YC → RGB converter 151 converts the YC signal into the RGB signal again, and the converted RGB signal is converted into the RGB signal. It is supplied to the image display LCD 15 via the driver 152. Based on the supplied RGB signals, the subject image is displayed on the LCD panel 150 of the image display LCD 15. The CCD 112, the A / D unit 113, and the WB / γ correction unit 114 operate in synchronization with the timing signal output from the CG 1121, and the image signal generated by the CCD 112 is processed at predetermined intervals. Therefore, on the display panel 150 of the image display LCD 15, the subject in the direction in which the photographing lens is directed is always displayed as a subject image. When the release button 102 is pressed during a photo opportunity while visually recognizing the subject image being displayed, all the image signals imaged on the CCD 112 are passed after a predetermined time from the timing when the release button 102 is pressed. Output as RGB signals. The RGB signal is converted into a YC signal by the YC processing unit 116, and the YC signal is further compressed by the compression / decompression unit 117, and the compressed image signal is recorded in the memory card 119. In the compression / decompression unit 117, the still image is compressed by a compression method based on the JPEG standard, and an image signal is recorded on the memory card 119. Compression information, shooting information, and the like are written in the header portion. When the mode lever 101e of the digital camera 100 is switched to the reproduction side, the header of the file is first read from the memory card 119, and the header in the header is read. After the compressed image signal in the file is expanded based on the compression information and restored based on the image signal, a subject image based on the image signal is displayed on the LCD panel 150 of the image display LCD 15.

  In addition to the main CPU 110, the digital camera 100 of this embodiment is provided with a photometric / ranging CPU 120 for performing focus adjustment and exposure adjustment. The photometric / distance CPU 120 uses the focus lens of the photographing optical system. Position control 1110 and switching control of the aperture 1112 are performed.

  The main CPU 110 notifies the photometry / ranging CPU 120 of the focus lens 1110 by notifying the photometry / ranging CPU 120 of the TTL distance measurement result when the photometry / ranging CPU 120 controls the position of the focus lens 1110. It is driven to the in-focus position. Depending on the photometric value, auxiliary light emission for accurately performing TTL distance measurement may be required. Therefore, if it is determined from the TTL photometry result that auxiliary light emission is necessary, the photometry / ranging CPU 120 is assisted. It notifies that it is necessary to perform light emission. In response to this notification, the photometry / ranging CPU 120 issues an instruction to the LD light emission control unit 18 to cause the LD light emission control unit 18 to emit light of the LD 181, or issues an instruction to the LED light emission control unit 19 to send the LED light emission control unit. By causing the white LED 191 to emit light, the emitted light is irradiated toward the subject as AF auxiliary light. The white LED 191 is the first auxiliary light emitter that emits light having a wide wavelength band toward the subject for detecting the subject contrast according to the present invention, and the LD 181 refers to the subject for detecting the subject contrast according to the present invention. This corresponds to the second auxiliary light emitter that emits light having a narrow wavelength band. When the main CPU 110 detects the subject contrast, the first auxiliary light is used when the subject distance is shorter than a predetermined distance according to the subject distance measured by the external AF unit including the AF sensor 14 and the photometry / ranging CPU 120. An LED emission control unit 19 that emits an LED 181 that is a light emitter, an LD light emission control unit 18 that emits an LD 181 that is a second auxiliary light emitter when the distance is longer than a predetermined distance; The photometry / ranging CPU 120 that gives a light emission instruction to 19 corresponds to the light emission control section referred to in the present invention.

  In the present embodiment, when the photometry / ranging CPU corresponding to the light emission control unit according to the present invention emits the xenon tube 160 and emits the emitted light from the xenon tube 160 toward the subject as photographing auxiliary light. Control is also performed. A flash emission timing control unit 140 is also provided so that the operation timing of the flash emission unit 16 that emits light from the xenon tube 160 can be accurately controlled in cooperation with the CG 1121.

  By doing so, the photometry / ranging CPU 120 can accurately control the driving of the focus lens 1110 and the emission timing of the LED 191 or LD 181 that emits AF auxiliary light by the same photometry / ranging CPU 120. The auxiliary light is effectively emitted during the AF search, and the main CPU 110 detects the object contrast with high accuracy.

  Here, the photographing process performed by the main CPU 110 when the power switch 101a is turned on, the photographing mode is designated by the mode lever 101e, and the release button 102 is operated will be described.

  FIG. 3 is a flowchart showing a procedure of photographing processing performed by the main CPU 110.

  In step S301, when the release button 102 is half-pressed, AE processing, that is, TTL photometry is performed, and the result is transmitted to the photometry / ranging CPU 120 to cause the photometry / ranging CPU 120 to change the aperture of the aperture 112. Similarly, in order to perform AF processing, that is, TTL distance measurement in the next step S302 when half-pressed, an instruction is first given to the photometry / ranging CPU 120 to move the focus lens 1110 along the optical axis while driving the focus lens 1110. The contrast is calculated based on the image signal obtained by the CCD 112. Then, the position where the calculated contrast is the largest is set as the in-focus position, and the in-focus position is notified to the photometry / ranging CPU 120, and the focus lens 1110 is moved to the in-focus position. When the release button 102 is fully pressed, an instruction is sent to the photometry / ranging CPU 120 in the next step S303 to supply an exposure start signal from the CG 1121 to the CCD 112 to start exposure. At the end of exposure, an exposure end signal is supplied from the CG 1121 to the CCD 112, and an image signal is output from the CCD 112 to the A / D unit 113 in the next step S304. In step S305, the A / D unit 113 converts an analog image signal into a digital image signal and supplies the converted signal to the white balance γ processing unit. In step S306, the white balance γ processing unit 114 performs image processing. Then, the image signal subjected to the image processing is output to the buffer 115. The image signal output to the buffer 115 is timed and transferred to the YC processing unit 116 to cause the YC processing unit 116 to perform image processing. The process proceeds to the next step, and the compression / decompression unit 117 performs image processing in step S307. After compression, in step S308, the I / F 118 performs recording on the recording medium, here, the memory card 119, and the processing of this flow ends.

  Here, the process of step S302 will be described in detail. Since the processing in step S302 is performed by the photometry / ranging CPU 120, which is the light emission control unit according to the present invention, based on the distance measurement result performed by the main CPU 110, the photometry / ranging CPU 120 will be described in the following description. This will be described as processing to be performed.

  FIG. 4 is a flowchart showing details of the AF process in step S302.

  When the AF process in step S302 is started, the process of this flow is started.

  In step S3021, first, the AF sensor 14 performs rough distance measurement, and based on the distance measurement result of the AF sensor 14, it is determined whether the subject is at a short distance, a long distance, or a distance measurement NG.

  If it is determined in step S3021 that there is a subject at a short distance, the process proceeds to the short distance side, and the LED 181 that is the first light emitter is selected in step S3022. If it is determined in step S3021 that the distance is long or NG, the process proceeds to step S3023 and the LD 191 that is the second light emitter is selected.

  Then, the process proceeds to the next step S3024, and the LD control unit 19 or the LED control unit 18 emits AF auxiliary light, and the main CPU 110 performs CCDAF, that is, TTLAF, and returns to the processing of the flow of FIG.

  In this way, for example, in the case of a shooting scene such as the above-mentioned commemorative shooting, AF auxiliary light is emitted from the LED 191 which is the first auxiliary light emitter. Since the light emitted from the LED 191 as the first light emitter is light in a wide wavelength band and is almost white light, even if the AF auxiliary light is irradiated at the place where the above-mentioned commemorative photographing is performed, other light is emitted. The photographer's shooting is not affected.

  In addition, when the subject is far away from the predetermined distance, for example, when shooting a scene that captures landscapes, the possibility that the angle of view of another photographer will overlap with the angle of view of the photographer is extremely reduced. Accordingly, it is possible to irradiate the AF auxiliary light so as to reach a far object using the second light emitter, for example, laser light having a narrow wavelength band and high emission power.

  FIG. 5 is a diagram illustrating the second embodiment, and is a diagram illustrating another example of the AF process of FIG.

  FIG. 4 shows an example in which the external AF sensor 14 is used to switch between the LD 181 and the LED 191 to emit light depending on whether the subject distance is a short distance or a long distance.

  On the other hand, in FIG. 5, using the fact that the AE process has been performed in step S301 shown in FIG. 3 and the field luminance has already been detected, the LED 191 or LD 181 is switched according to the field luminance. It has been improved. In this embodiment, when detecting the subject contrast, the photometry / ranging CPU 120 emits the LED 191 that is the first auxiliary light emitter when the luminance is higher than a predetermined luminance in accordance with the subject luminance measured by the TTL metering. When the luminance is lower than the predetermined luminance, the LD 181 that is the second auxiliary light emitter is caused to emit light. However, in some cases, the brightness is so bright that it does not require the emission of AF auxiliary light far beyond the predetermined brightness. Therefore, this case is described as high brightness in the flow, and the brightness is higher than the predetermined brightness in the present invention. The case of is described as medium luminance.

  If it is determined in step S3021 that the luminance of the field obtained by the AE process in step S301 in the flowchart of FIG. 3 is high and it is determined that the luminance is high enough not to emit auxiliary light, the auxiliary light needs to be emitted. Therefore, the process jumps to step S3025, performs CCDAF, that is, TTL distance measurement, ends the processing of this flow, and returns to the processing of the flow of FIG.

  If it is determined in step S3021 that the luminance is equal to or higher than the predetermined luminance and is equal to or higher than the intermediate luminance that requires auxiliary light emission, the process proceeds to the intermediate luminance side, and the LED 191 is selected in step S3022. If it is determined in step S3021 that the luminance is lower than the predetermined luminance and low, the process proceeds to step S3023 and the LD 181 is selected.

  After proceeding to step S3024, the LD light emission control unit 18 causes the LD 181 to emit light, or the LED light emission control unit 19 causes the LED 191 to emit light, and the process proceeds to the next step S3025. In step S3025, the main CPU 110 performs CCDAF, that is, TTLAF, ends the processing of this flow, and returns to the processing of the flow in FIG.

  In this way, white LED light is used for AF auxiliary light in shooting scenes that take commemorative pictures outdoors in the daytime, or in shooting scenes that take commemorative pictures indoors where a relatively bright indoor light is on. Is emitted toward the subject, so that it does not affect the shooting of other people.

  In addition, when the field brightness is low, a relatively distant landscape such as a night scene is often photographed. In such a case, although it is colored, the second light emitter referred to in the present invention has a high output. The AF auxiliary light can be irradiated using laser light.

  FIG. 6 is a diagram for explaining the third embodiment.

  The configuration of the digital camera 100A shown in FIG. 6 is for switching between the AF auxiliary light irradiation mode by the LED 191 that is the first auxiliary light emitter and the AF auxiliary light irradiation mode by the LD 181 that is the second auxiliary light emitter. 1 is exactly the same as that shown in FIG. 1 except that the user operator 101f is provided on the back of the camera body. Further, the configuration of the signal processing unit inside the digital camera shown in FIG. 6 is exactly the same as the configuration of FIG. 2 except for the portion where the operator from the user operator is supplied to the main CPU 110.

  In the digital camera 100A shown in FIG. 6, when the main CPU 110 (see FIG. 2) detects the subject contrast, the photometry / ranging CPU 120 (see FIG. 2) corresponding to the light emission control unit according to the present invention according to the switching state by the user operator. ) Is improved so that the LED 191 (see FIG. 2) as the first auxiliary light emitter or the LD 181 (see FIG. 2) as the second auxiliary light emitter emits light.

  FIG. 7 is a flowchart showing a procedure of auxiliary light emission processing performed by the photometry / ranging CPU 120 (see FIG. 2).

  In step 3021, the switching position of the user operator 101 f is determined. If it is determined in step S3021 that the user operation element 101f has been switched to the LED side, the process proceeds to the LED side, selects the LED 191 that is the first light emitter, and determines that the user operation element 101f has been switched to the LD side. Then, proceed to the LD side and select the LD 181 as the second light emitter.

  Proceeding to the next step S3024, in step S3024, the LD control unit or the LED control unit is caused to emit AF auxiliary light. In step S3025, the main CPU performs CCDAF, that is, TTLAF, and the process returns to the flow of FIG.

  If the user operation element 101f is provided in this way and the user operation element 101f allows the user to select either the first light emitter or the second light emitter, the user operation element 101f can be selected according to the shooting scene. Thus, either the LD 181 or the LED 191 is selected by the user operation.

  By doing so, it is left to the user judgment as to which of the LED 191 and the LD 181 is preferably used as the auxiliary light emitter according to the shooting scene, and the AF auxiliary light according to the shooting scene is set based on the user judgment. You can shoot with flashing.

  FIG. 8 is a diagram for explaining the fourth embodiment.

  The configuration of the digital camera 100B shown in FIG. 8 switches between a normal AF mode with a relatively long shutter time for generating an image signal for focus adjustment and a high-speed AF mode with a relatively short shutter time. 1 is exactly the same as that shown in FIG. 1 except that the user operator 101g is provided on the back of the camera body. Also, the configuration of the signal processing unit inside the digital camera shown in FIG. 8 is exactly the same as the configuration of FIG. 2 except for the part where the operation signal from the user operator 101g is supplied to the main CPU 110.

  In the digital camera 100B shown in FIG. 8, when the main CPU 110 detects the object contrast, the photometry / ranging CPU 120 (see FIG. 2) corresponding to the light emission control unit according to the present invention is the first according to the switching state of the user operator. The LED 191 (see FIG. 2), which is an auxiliary light emitter, or the LD 181 (see FIG. 2), which is a second auxiliary light emitter, is caused to emit light.

  In the normal mode, since the shutter time per time for generating an image signal for focus adjustment is relatively long, an LED having a relatively small emission power is used, and the shutter time per time is relative. In the case of a short high-speed mode, a high output LD is used because the amount of light for generating an image signal for focus adjustment is required in a short time.

  FIG. 9 is a flowchart showing a procedure of auxiliary light emission processing performed by the photometry / ranging CPU provided in the digital camera shown in FIG.

  In step S3021, the switching position of the mode user operator 101g is determined. If it is determined in step S3021 that the mode user operation element 101g has been switched to the normal mode side, the process proceeds to the LED side, an LED is selected in step S3022, and if it is determined that the user operation element has been switched to the high speed mode side, LD is performed. In step S3023, the LD is selected.

  In step S3024, the AF control light is emitted from the LD control unit 18 or the LED control unit 19, and the main CPU 110 performs CCDAF, that is, TTLAF, and the process returns to the flow of FIG.

  In this way, the user operation element 101g is provided, the user is notified in advance of the type of AF auxiliary light in the normal mode and the high speed mode selected by the user operation element 101g, and the user is notified of this according to the shooting scene. The user operation element may be switched.

  Then, the user determines which of the high-speed mode and the normal mode is preferable according to the shooting scene, and either the LD or the LED is selected by the user operator according to the shooting scene, and shooting is performed. It becomes like this.

  As described above, it is possible to realize an imaging apparatus that can selectively use laser light and LED light according to an imaging scene.

It is a figure which shows the digital camera which is 1st Embodiment of the imaging device of this invention. FIG. 2 is a configuration block diagram of a signal processing unit provided in the digital camera 100 of FIG. 1. It is a flowchart which shows the procedure of the imaging | photography process which main CPU110 performs. It is a flowchart which shows the detail of AF process of step S302. It is a figure explaining 2nd Embodiment and is a figure which shows another example of AF process of FIG. It is a figure explaining 3rd Embodiment. It is a flowchart which shows the procedure of the auxiliary light emission process which photometry and ranging CPU perform. It is a figure explaining 4th Embodiment. It is a flowchart which shows the procedure of the auxiliary light emission process which photometry and ranging CPU perform.

Explanation of symbols

100 100A 100B Digital camera 101f User operation element 101g User operation element 102 Release button 105 Viewfinder 14 AF sensor 141 142 Distance window 16 Flash light emitting unit 160 Xenon tube 170 Lens barrel 18 LD light emission control unit 180 Light emission window 181 LD
19 LED light emission control unit 190 Light emission window 191 LED

Claims (5)

In an imaging device that detects the subject contrast and adjusts the focus prior to the shooting operation,
A first auxiliary light emitter for irradiating light with a relatively wide wavelength band toward the subject for subject contrast detection;
A second auxiliary light emitter that emits light with a relatively narrow wavelength band toward the subject for subject contrast detection;
An imaging apparatus comprising: switching means for switching between the first auxiliary light emitter and the second auxiliary light emitter. A subject image is formed on the image sensor by a photographing optical system including an optical member for focus adjustment, an image signal for adjustment is repeatedly generated prior to photographing, and a subject contrast is detected based on the image signal for adjustment. In the photographing apparatus for performing the focus adjustment and generating and recording the image signal for recording according to the photographing operation,
An external AF unit having a distance sensor separate from the image sensor and measuring the distance to the subject using the distance sensor;
A first auxiliary light emitter for irradiating light with a relatively wide wavelength band toward the subject for subject contrast detection;
A second auxiliary light emitter that emits light with a relatively narrow wavelength band toward the subject for subject contrast detection;
When detecting the object contrast, the first auxiliary light emitter is caused to emit light when the distance is shorter than a predetermined distance according to the object distance measured by the external AF unit, and when the distance is longer than the predetermined distance. An imaging apparatus comprising: a light emission control unit that causes the second auxiliary light emitter to emit light. A subject image is formed on the image sensor by a photographing optical system including an optical member for focus adjustment, an image signal for adjustment is repeatedly generated prior to photographing, and a subject contrast is detected based on the image signal for adjustment. In the photographing apparatus for performing the focus adjustment and generating and recording the image signal for recording according to the photographing operation,
A metering unit for measuring the field luminance;
A first auxiliary light emitter for irradiating light with a relatively wide wavelength band toward the subject for subject contrast detection;
A second auxiliary light emitter that emits light with a relatively narrow wavelength band toward the subject for subject contrast detection;
In detecting the subject contrast, the first auxiliary light emitter is caused to emit light when the luminance is higher than a predetermined luminance according to the luminance of the subject measured by the photometry unit, and when the luminance is lower than the predetermined luminance, An imaging apparatus comprising: a light emission control unit that emits light from the second auxiliary light emitter. A subject image is formed on the image sensor by a photographing optical system including an optical member for focus adjustment, an image signal for adjustment is repeatedly generated prior to photographing, and a subject contrast is detected based on the image signal for adjustment. In the photographing apparatus for performing the focus adjustment and generating and recording the image signal for recording according to the photographing operation,
A first auxiliary light emitter for irradiating light with a relatively wide wavelength band toward the subject for subject contrast detection;
A second auxiliary light emitter that emits light with a relatively narrow wavelength band toward the subject for subject contrast detection;
A user operator for switching between irradiation by the first auxiliary light emitter and irradiation by the second auxiliary light emitter;
An imaging apparatus comprising: a light emission control unit configured to emit light from the first auxiliary light emitter or the second auxiliary light emitter according to a switching state by the user operation when detecting a subject contrast. . A subject image is formed on the image sensor by a photographing optical system including an optical member for focus adjustment, an image signal for adjustment is repeatedly generated prior to photographing, and a subject contrast is detected based on the image signal for adjustment. In the photographing apparatus for performing the focus adjustment and generating and recording the image signal for recording according to the photographing operation,
A first auxiliary light emitter for irradiating light with a relatively wide wavelength band toward the subject for subject contrast detection;
A second auxiliary light emitter that emits light with a relatively narrow wavelength band toward the subject for subject contrast detection;
A user operator for switching between a normal AF mode with a relatively long shutter time for generating the adjustment image signal and a high-speed AF mode with a relatively short shutter time;
When detecting the subject contrast, the first auxiliary light emitter emits light when the mode is switched to the normal AF mode according to the switching state by the user operator, and the mode is switched to the high-speed AF mode. An imaging apparatus comprising: a light emission control unit that causes the second auxiliary light emitter to emit light.

Images