JPS61159611A - Camera equipped with automatic focus adjusting means and its interchangeable lens - Google Patents

Abstract

PURPOSE:To prevent wrong range measuring operation which is performed when an interchangeable lens whose focus can not be detected is mounted by performing and inhibiting automatic focus adjusting operation according to information, showing whether range measuring operation can be performed through an interchangeable lens, inputted from the interchangeable lens side. CONSTITUTION:A microcomputer (MCP) 22 is incorporated in a camera body 21 and a data circuit 24 which outputs data information characteristic to an interchangeable lens 23 to the MCP22 is incorporated in the lens 23 mounted on the body 21. The MCP22 reads various kinds of information on characteristic functions of the lens 23 out of the circuit 24 and performs the exposure and automatic focus adjustment of the camera. The lens 23 is mounted on the body 21, and data are readout of the circuit 24 to the MCP22, which performs arithmetic as to the exposure and decides whether the automatic focus adjustment is possible or not. At this time, when the lens 23 has an open aperture value darker (lighter) than constant brightness, light measuring operation is repeated without starting the automatic focus adjusting opera tion and a release interruption is expected. When the adaptivity of the lens 23 is good, said adjusting operation is started.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a camera equipped with a means for measuring distance by receiving light passing through a photographic lens and automatically adjusting focus according to the result, and an interchangeable lens thereof. .

(Prior art) The first part and the second part of the photographic lens sandwich the optical axis of the photographic lens.
Cameras equipped with distance measuring systems that measure distances by detecting the correlated positions of two images created by subject light beams that have passed through the respective portions are well known. The basic configuration of the distance measuring optical system is shown in Figure 3.
A condenser lens 3 is disposed near a position 2 equivalent to the planned focal plane of the photographing lens 1, and an imaging lens 4.5 is disposed behind the condenser lens 3. A line sensor 7.8 is arranged. The line sensor 7 has a so-called front-focus image 9a in which the image of the object to be focused is formed in front of the planned focal plane.
．． Re-imaging lOa and LLa in the area of 8 are mutually optical axis 12
re-imaging 10b of the image 9b of the rear bin,
11b move away from the optical axis 12 from each other. In the case of focusing, the distance between two mutually corresponding points of re-imaging 10 and 11 of the image 9 has a specific size determined from the configuration of the optical system.

Therefore, by converting the light distribution pattern of the image on the line sensor 7.8 into electrical signals and determining their relative positional relationship, the distance to the object to be focused can be determined.

In the distance measuring system as described above, the entrance pupil planes A and B seen from the distance measuring optical system for re-imaging lO and 1 are located on both sides of the optical axis 12 of the photographing lens l. In the case of a refractive type interchangeable lens as shown in Fig. 3, these entrance pupil planes A and B are the same as those of the taking lens l itself at the darkest open aperture value due to a series of operations such as extending and zooming the taking lens l. In order to prevent the line sensor 7.8 from receiving an image in which some of the light rays are kicked out on the pupil, the entrance pupil planes A and B are included in the aperture area of the photographing lens I corresponding to the open aperture value. A distance measuring optical system is configured.

(Problems to be Solved by the Invention) By the way, even with the above-mentioned refractive type photographic lens l, there is a curve as shown in FIG. , h, h, and h3, the amount of spherical aberration changes as the distance from the optical axis I2 increases,
When a so-called Paris soft lens, which adjusts the degree of softness of the image 13 on the shooting screen, is attached as an interchangeable lens to a camera having a distance measuring optical system as described above, as the degree of softness increases from zero, In Figure 4, the dashed line indicates 1.
．． As shown by kt and 3, the best image plane position of the film plane equivalent position at each softness level changes greatly. On the other hand, as explained in FIG. 3, the distance measuring optical system is configured so that the entrance pupil planes A and B are included in the area corresponding to the darkest aperture value of the photographing lens l. The distance-measuring optical system is viewing the image 13 in the area between the optical axis 12 and the outer edge 14 of the above-mentioned area in FIG. The position you are looking at will shift significantly. For this reason, accurate distance measurement becomes impossible.

In addition, as shown in FIG.
Therefore, the light rays near the optical axis 12 are blocked, and the lower principal rays are kicked off at the entrance pupil planes A and B, and object information is not correctly projected onto the line sensor 7.8.
A distance measurement error occurs.

Furthermore, although not specifically illustrated, in a shift lens that can shift the lens in the X-axis direction and the y-axis direction,
Depending on the amount of shift of the lens, the viewing position of the distance-measuring optical system shifts from the optical axis, so the relationship with the best image plane position of the film etc. cannot be maintained correctly, and as shown in Figure 3. At the entrance pupil planes A and B, the upper principal ray or the lower principal ray is kicked out, making accurate distance measurement impossible.

Therefore, when a camera equipped with a distance measurement system as shown in Fig. 3 is attached with an interchangeable lens such as the above-mentioned Paris soft lens, reflective telephoto type photographing lens 15, or shift lens, the distance measurement system will be able to perform accurate measurement. If distance measurement cannot be performed and automatic focus adjustment is performed based on this result, there is a problem in that photographing will be performed based on inaccurate distance measurement results.

The present invention has been made to solve the above-mentioned problems, and it is difficult to perform accurate distance measurement with the above-mentioned distance measurement system, such as a Paris soft lens, a reflective telephoto type lens, or a shift lens. If an interchangeable lens that cannot be used is attached to the camera body, automatic focus adjustment will be prohibited.
It is an object of the present invention to provide a camera equipped with an automatic focus adjustment means that eliminates failures in photographing, and an interchangeable lens thereof.

(Means for Solving the Problems) The first invention of the present application is provided with a distance measuring means for measuring a distance by receiving light passing through an interchangeable lens on the camera body side, and the interchangeable lens is grown on the interchangeable lens side. The present invention is characterized in that it includes an information means for outputting information regarding whether distance measurement is possible or not by the distance measurement means. In other words, the information means on the interchangeable lens side outputs unique information about whether distance measurement is possible or not, which the interchangeable lens has, and the automatic focus adjustment means on the camera body receives this information and adjusts the attached interchangeable lens to distance measurement. It is determined whether the distance measurement is compatible or not, and automatic focus adjustment is prohibited if the distance measurement is not compatible. Therefore, it is possible to reduce failures in photographing due to the use of interchangeable lenses that are not compatible with distance measurement.

A second invention of the present application is characterized in that the interchangeable lens is equipped with information means that outputs unique information regarding whether distance measurement is possible or not, which the interchangeable lens has.

In other words, since the interchangeable lens outputs information regarding whether or not distance measurement is possible, by attaching the interchangeable lens to the camera body, it is possible to easily determine whether automatic focus adjustment is possible.

(Function) In the first invention of the present application, the information means provided on the interchangeable lens side outputs unique information of the interchangeable lens regarding whether distance measurement is possible or not to the distance measurement means on the camera body side. On the other hand, the distance measuring means provided on the camera body side receives the above information regarding distance measurement capability of the interchangeable lens attached to the camera body, determines the compatibility of the distance measurement, and replaces the interchangeable lens that is not compatible with the distance measurement. In the case of lenses, distance measurement is prohibited. This eliminates failures in shooting due to automatic focus adjustment when using interchangeable lenses that are not compatible with distance measurement.

In the second invention of the present application, the information means holds unique information of the interchangeable lens regarding distance measurement capability, and based on this information, if the interchangeable lens is attached to the camera body, it is determined whether automatic focus adjustment is possible. can be easily determined.

(Example) Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 shows an electric circuit of a camera and its interchangeable lens equipped with an automatic focusing means according to the present invention.

In FIG. 1, a micro combinator 22 is incorporated in a camera 21m. In addition, the above camera body 2
A data circuit 24 is incorporated in the interchangeable lens 23g1Il to be attached to the camera body 21. The data circuit 24 outputs the unique data information of the interchangeable lens 23 to the microcomputer 22 on the camera body 21 side.

The microcomputer 22 on the camera body 21 side supplies clock pulses to the data circuit 24 on the interchangeable lens 23 side, and based on the count value of this clock pulse, the read-only memory of the data circuit 24 built into the interchangeable lens 23 (Hereinafter, abbreviated as ROM) 25 reads out various information based on the functions specific to the interchangeable lens 23, and performs exposure control and automatic focus control of the camera.

Therefore, on the camera body 21 side, together with the microcomputer 22, there is a distance measuring element 26. A drive control circuit 27 for a motor M that drives the interchangeable lens 23 to the in-focus position and a photometry device 28 are incorporated. Camera body 2 above
1 also includes a setting device 29 for setting shooting modes such as program mode, aperture priority mode, shutter speed priority mode, and manual mode, film sensitivity, calibration value, shutter speed, etc. Exposure control device 30° for controlling exposure; display device 31 and buffer 32 for displaying exposure data, distance measurement data, data possessed by the interchangeable lens 23, etc.
It is equipped with When a power supply signal is input from the microcomputer 22, this buffer 32 is connected to the interchangeable lens 22.
The power supply Vcc is supplied to the data circuit 24 on the side.

The microcomputer 22 includes a serial I10 port 33 and an analog/digital conversion circuit (hereinafter referred to as A/D converter circuit).
It is abbreviated as a D conversion circuit. )34. The serial port 33 supplies a clock pulse to the data circuit 24 of the interchangeable lens 23, and the data circuit 24 of the interchangeable lens 23.
Capture the serial data input from the 4th side. Also, A
The /D conversion circuit 34 converts the analog photometry output and photometry reference voltage V ref inputted from the photometry device 28 into digital signals.

On the other hand, the data circuit 24 on the side of the interchangeable lens 23 is connected to the ROM2
It consists of a 5.3-bit binary counter 35, 36° address decoder 3F0, a manual switching circuit 38, and an 8-bit parallel/serial conversion circuit 39.

The above 3-bit binary counter 35 is connected to the camera body 2.
An interchangeable lens that outputs one pulse for every eight clock pulses supplied from the microcomputer 22 on the first side to the next stage 3-bit binary counter 36, and serially outputs from the 8-bit parallel/serial conversion circuit 39. 23
Controls the output timing of data information.

Another 3-bit binary counter 36 outputs the output signals shown in Table 1 below in response to the pulses input from the 3-bit binary counter 35.

is output to the address decoder 37.

(Leaving space below) Table 1 The above address decoder 37 outputs output signals for addressing the ROM 25 and L4 to the ROM 25 and the input switching circuit 3, respectively, based on the information of the output signal L1.
Output to 8. The output signal L4 specifies the upper 3 bits of the 8 bits of the address, and the output signal L4 specifies the lower 5 bits of the 8 bits of the address.

The lower 5 bits of the 8 bits of the address of the ROM 25 can also be set by an external signal Ls-IL@-1. The external signal -1 is a signal corresponding to the focal length when the interchangeable lens 23 is a zoom lens, and this external signal -1 is generated from the zoom encoder contact piece 41b by operating the zoom operation ring 41. be done. In the case of a fixed focus lens, the zoom encoder contact piece 41
b are all set to a non-conducting state with respect to the earth encoder contact piece 41a. Another external signal, -1, is generated by the autofocus enable/disable switchable encoder contact piece 41c.

Switching of the lower 5 bits of designation information, L, of the ROM 25 is performed inside the manual switching circuit 38 by the output signal 3 of the address decoder 37, and the output signal of the input switching circuit 38 is changed to the lower 5 address of the ROM 25. Finalize the bits.

Address decoder 37 human output and human power switching circuit 38
The input/output relationship is shown in Table 2 below.

(The following is a blank space.) That is, if L = ``00'', L5 = L4, and if L = ``01'', =L, -1 and the lower 5 bits of the address are respectively specified.

Also, if L=“10”, the lower 5 to 1 bits are
=L, but only the least significant bit depends on L6-2, and if the earth encoder contact piece 41a and enable/disable switchable enhancer contact piece 41c are non-conductive, Ls="00101", and if conductive, Ls="00100". ” address is specified.

Next, information stored in the ROM 25 of the data circuit 24 will be explained.

The types of information are "incomplete attachment check code", "open aperture", "minimum comparison value", "open aperture metering a1% difference correction", "focal length", [lens extension amount conversion coefficient], "for automatic focus" There are a total of eight types: "open aperture value" and "autofocus enable/disable determination information".

The [Incomplete Attachment Check Code] is read out from the camera first, and is a regular code, such as “1010101.”
0'' is read, the camera body 21 determines that the interchangeable lens 23 is correctly attached, and assumes that the information from the interchangeable lens 23 is valid.When a regular code is not read, , it is assumed that the information from the interchangeable lens 23 is invalid.

"Open aperture value" and "minimum comparison value" are known open aperture values F)g
.

and minimum comparison value AV (7) Conversion formula AV=2XIOggFIQ
Interchangeable lenses in 1/8EV increments after conversion 21) ROM25
It is described in For example, if FNO=1.68, AV=
It is written as 1+4/8, that is, “oooootloo”, and when FNO=32, AV=10+0/8, that is, “
01010000”.

"Aperture photometry error correction" is data for correcting the aperture photometry characteristics of each interchangeable lens and the camera's photometry device, and is stored in the ROM 25 of the interchangeable lens 23 in units of 178EV, same as the "open aperture value" and "minimum comparison value". It is described in

"Focal length" is written in abbreviated form, with r representing the focal length and FQ representing its converted value. For example, f=50 dragon, 10
In the case of 0+u, 2005m, each F&=24 is “0oot
“toooo”, F12=32 is “ootoooooo”.

FQ=40 is expressed as "00101000". In other words, each time the focal length r doubles, the focal length conversion value F
12 increases by 8.

The "lens extension amount conversion coefficient" is the amount of defocus of the subject image when the film is equidisplaced, obtained from the output of the microcomputer 22 of the camera body 21, that is, the ratio of the defocus amount ΔL and the lens extension amount ΔL. It is a value proportional to □, and Δd When actually controlling the interchangeable lens 23, the amount of extension of the interchangeable lens 23 is detected based on the rotation of a lens drive focus control motor M, which will be described later, inside the camera body 21. The ratio between the number of output pulses of the detection system and the amount of defocus on the image plane is used, and its unit is pulse/μ■.

Next, the "open aperture value for autofocus" and the "autofocus enable/disable determination information" will be explained.

First, the "open aperture value for autofocus" is determined by a series of operations such as extending the interchangeable lens or zooming, and then setting the maximum aperture comparison value F'NO at the darkest point in the ROM 25 of the interchangeable lens 23.
For example, in FIG. 3, this is used to determine whether the upper principal rays of each of the entrance pupil planes A and H are eclipsed. Data is written using "open comparison value"
is the same as

Next, [autofocus enable/disable determination information] is information used to judge the compatibility of the distance measuring optical system of the interchangeable lens 23 and the camera body 21 as an element other than the [autofocus aperture comparison value]. A normal interchangeable lens 23 is described as "bi" and is said to have good compatibility, but the following interchangeable lens 23
3 is described as 0" and is considered to have poor compatibility. In other words, automatic focus control is impossible.

That is, in a reflective telephoto type lens, as already explained in FIG. Since the light beam is eclipsed, object information is not correctly projected onto the line sensor 7.8, causing a distance measurement error. Therefore, the ``autofocus enabled/disabled'' information in the ROM 25 of the reflective telephoto type interchangeable lens 23 is
“0” is written as “judgment information”.

In addition, we have already developed the 4th version of the Paris Soft Lens, which allows the degree of softness to be adjusted by consciously changing the amount of spherical aberration.
As explained using the figure, accurate distance measurement becomes impossible. Therefore, at the position where the softness is zero, the ROM25
"B" is written in the "auto focus enable/disable determination information" of
“0” is written to the ROM 25 at a position where the softness level is other than zero.

In addition, here, when the softness is zero, there is only the collapse of spherical aberration,
Softness level is 1.2. As the situation progresses, the fall becomes greater.

Switching between zero and other degrees of softness is manually performed by the manual switching circuit 38 using the enable/disable switching encoder contact piece 41c, and the conduction/non-conduction between the earth encoder contact piece 41a and the autofocus enable/disable switch encoder contact piece 41c. Depending on the state of continuity “
B or “0” is selected.

In addition, with a shift lens that can be shifted in the At the same time, the upper principal ray or the lower principal ray is vignetted at the entrance pupil planes A and H in FIG. Therefore, at a position where the shift amount is zero in both the x and y directions (there is no deviation of the optical axis), R
In the "autofocus enable/disable determination information" of the OM25, "B" is written, and "°0" is written at a position other than zero. That is, switching between zero and other shift amounts is input to the input switching circuit 38 by the enable/disable switching encoder contact piece 41c, and conduction between the earth encoder contact piece 41a and the autofocus enable/disable switch encoder contact piece 41c.・“BI” or “0” is selected depending on the non-conducting state.

The relationship between the types of data stored in the ROM 25 and addresses described above is shown in Table 3 below.

(Margin below) Table 3 Note 2 However, “φ” represents “0” or “bi”.

The ROM 25 stores 8-bit parallel data fixedly stored at the address specified by the signal L2-Ls.
The signal is sent to an 8-bit parallel/serial conversion circuit 39. The 8-bit parallel/serial conversion circuit 39 receives data from the ROM 25.
Bit-parallel data, for example 8 bits sequentially starting from the least significant bit.
Convert to bit serial data. The timing control is
This is done using the output signal of the 3-bit binary counter 37.

Table 4 shows the logical table.

(Left below) Note = b0...Lowest bit b,...Most significant bit The data circuit 24 explained above is the same as the interchangeable lens 2.
By attaching the lens 3 to the camera body 21, the interchangeable lens 23
The power contact 42a, ground contact 43a, reset contact 44a, clock pulse contact 45a, and data output contact 46a provided on the camera body 21 side are the same as the power contact 42b, ground contact 43b, and reset contact 4 provided on the camera body 21 side.
4b, a clock pulse contact 45b and a data output contact 46b, and is connected to the microcomputer 22 on the camera body 21 side.

Next, the operation of the camera shown in FIG. 1 will be explained with reference to the flowchart shown in FIG.

When photographing, first, after attaching the necessary interchangeable lens 23 to the camera body 21, the power switch 47 provided on the camera body 21 side is turned on (step 100 in FIG. 2).
After the initial setting operation, the microcomputer 22 performs the second
Step 101 in the figure is executed to disable release interrupts.

Thereafter, the microcomputer 22 executes step 102, determines whether the photometry switch 48, which is turned on by pressing the shirt release button or the like provided on the camera body 21 side in one step, is on. If not on, step 102 is repeatedly executed.

In this state, point the camera at the subject and press the metering switch 4.
is turned on, the microcomputer 22 executes step 103.

In step 103, the microcomputer 22 first starts supplying the power supply voltage Vcc to the interchangeable lens 23 via the buffer 32. Thereafter, the data circuit 24 is reset by changing the reset pulse from "low" to "high". After the reset operation is completed, the microcomputer 22 starts sending out clock pulses. 3-bit binary counter 35 is 8
For each clock pulse, one pulse is sent to the next stage.
Sends to bit binary counter 36. The 3-bit binary counter 36 sequentially generates a signal of 1 in response to the pulses sent from the 3-bit binary counter 35, and sends it to the address decoder 37. The human output relationship of the 3-bit binary counter 36 is as shown in Table 1.

The address decoder 37 reads the ROM from the 3-bit binary counter 36 based on the information of the signal output from the 3-bit binary counter 36.
25 and generates L4.

Lower 5-bit binary specification information of ROM25 L4゜L@
As already explained, the switching is performed by the address decoder 3.
The output of 7 is performed inside the input switching circuit 38 by the output 3, and the output of the input switching circuit 38 is output.

finally determines the lower 5 bits of the ROM 25 address.

Input/output of address decoder 37 and input switching circuit 38
The input/output relationship is as shown in Table 2.

The ROM 25 sends the 8-bit parallel data written to the address designated by the signals L2 and R to the 8-bit parallel/serial conversion circuit 39.

The 8-bit parallel/serial conversion circuit 39 converts the 8-bit parallel data received from the ROM 25 into 8-bit serial data, starting from the least significant bit, and outputs the data to the data output contact 46a.
, 46b to the microcomputer 22 on the camera body 21 side.

Data is read from the data circuit 24 on the interchangeable lens 21 side in the sequence described above.

The microcomputer 22 has the following functions for the interchangeable lens 23:
After sending out 64 clock pulses, the reset pulse is set to "low" and data from the ROM 25 of the interchangeable lens 23 is received from the serial I10 boat 33.

Next, the microcomputer 22 performs step 104.
105 is executed, the photographing mode, set comparison value AV, and shutter speed TV are read from the setting device 29, and photometry is started by the photometry device 28. The photometric output and the photometric reference voltage V ref are input to the A/D conversion circuit 34, and the photometric output is quantized.

After that, the microcomputer 22 performs step 106.
.
Exposure-related calculations are performed based on the "minimum comparison value" and "aperture metering error correction" and in consideration of the photographing mode from the setting device 29. The calculated results are displayed on the display device 31 and are also sent to the exposure control device 30. At this stage, the microcomputer 22 cancels the inhibition of interrupts caused by the release operation, and enters a release-enabled state.

The microcomputer 22 then executes step 109, and a release switch (not shown) is turned on by pressing the shutter button in the second step.

) is on.

If it is determined in step 109 that the release switch is on, the microcomputer 22 determines in step 110 whether automatic focus control is possible or not.

First, check the autofocus dose and discharge value, and if the interchangeable lens 23 has an open aperture that is darker than a certain brightness, return to the lens data reading routine without starting autofocus operation. Repeat photometry and wait for release interrupt.

On the other hand, if the interchangeable lens 23 has an open aperture that is brighter than a certain brightness, then the "autofocus barrel/impossibility determination information" is checked. Based on this information, the compatibility with the distance measuring optical system inside the camera body 21 is checked, and if the compatibility is poor, the data of the interchangeable lens 23 is checked again without starting the automatic focus control operation. Return to the reading routine, repeat photometry, and wait for the release interrupt.

On the other hand, if the compatibility of the interchangeable lens 23 is good, the microcomputer 22 executes step III and starts automatic focus control operation. That is, the microcomputer 22 calculates the amount of defocus at the equivalent position on the film surface based on the output from the distance measuring element 26, multiplies the calculated amount of defocus by the "lens extension amount conversion coefficient" of the lens information, and performs the replacement. After calculating the number of pulses required to drive the lens 23, driving of the interchangeable lens 23 is started.

Next, the process returns to the routine for reading the defocus of the interchangeable lens 23. If the automatic focus control operation is completed, wait for a release interrupt (steps 112 and 11).
3) Become.

When the release operation is performed in the above state, the microcomputer 22 enters the interrupt processing routine of steps 114, 115, 116, and 117 to check whether winding is complete.
After stopping the automatic focus control operation, the exposure control device 30 controls the shutter speed and aperture determined by exposure calculation.
The process is completed at step 118.

As described above, based on the data information read from the data circuit 24 built into the interchangeable lens 23, execution and prohibition of execution of the distance measurement operation are received based on information regarding distance measurement capability of the interchangeable lens 23. is determined automatically.

(Effect of the invention) As is clear from the detailed description above, the first aspect of the present application
According to the invention, the automatic focus adjustment operation is automatically executed or prohibited from being executed based on the information input from the interchangeable lens regarding whether distance measurement is possible with the interchangeable lens. It is possible to prevent distance measurement by the distance measurement system from being carried out.

Further, according to the second invention of the present application, since the interchangeable lens itself can have information regarding whether or not distance measurement is possible, the focus adjustment system This eliminates the need to switch between automatic and manual mode.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram of an electric circuit installed in a camera body equipped with a distance measuring system according to the present invention and its interchangeable lens, and FIG. 2 is a 70-chart of the operation of the electric circuit in FIG. 1. Fig. 3 is an explanatory diagram of the distance measuring optical system of the camera, and Fig. 4 is an explanatory diagram showing the relationship between the best position of the film surface equivalent position according to the amount of spherical aberration of the lens and the image seen by the distance measuring optical system. FIG. 5 is an explanatory diagram of the entrance pupil plane of the distance measuring optical system in a reflective telephoto lens. 21... Camera body, 22... Microcomputer, 23... Interchangeable lens, 24... Data circuit,
25... ROM, 26... distance measuring element.

Claims (2)

[Claims] (1) The camera body side is equipped with a distance measuring means that measures distance by receiving light that has passed through the lens, while the interchangeable lens attached to the camera body is equipped with a distance measuring means that is included in this interchangeable lens. An automatic focusing device comprising: an information means for outputting information regarding whether distance measurement is possible or not, and determining execution or prohibition of execution of an automatic focus adjustment operation based on information regarding whether distance measurement is possible from an interchangeable lens attached to a camera body. Camera with adjustment means. (2) An automatic device characterized by comprising an information means for outputting information regarding whether distance measurement is possible by the distance measurement means provided on the camera body side, and outputting information regarding whether distance measurement is possible or not to the camera body side. Interchangeable camera lens with focus adjustment means.