JPS63172248A - Camera with auto-focusing device - Google Patents

Abstract

PURPOSE:To absorbe an error included in an arithmetic stop and to photograph two always different objects under respectively focused states by offsetting the arithmetic stop to the stop side by a fixed value. CONSTITUTION:Since a lens is moved to a lens position capable of focusing an object A, a defocused value from an object B is calculated and the lens is moved up to an intermediate position of the defocused value, a focus detecting error in focus detecting operation for detecting defocusing and a position control error in a lens driving mechanism for moving the lens to the intermediate position exert influence upon stopping operation. Thereby, a computer PRS calculates a stop value obtained by offsetting an arithmetic stop value to the stopping side by a fixed value and executes practical stop control by using the offset stop value. Consequently, the error is absorbed and the focused states of both the objects are always guaranteed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a camera having an automatic focus adjustment device that allows photographing two subjects located at different positions to be in focus.

(Prior art) When subjects A and B are located at different positions, find the intermediate position between the lens position that focuses on subject A and the lens position that focuses on subject B, and set the lens position to this intermediate position. While moving the lens, the aperture is determined by dividing the amount of defocus between the lens positions for subjects A and B by the circle of least confusion, and the aperture is used to capture the subject A.

Subjects A and B at different positions, with B both within the same depth.
The applicant of the present application filed Japanese Patent Application No. 61-23684 for a camera with an automatic focus adjustment device that guarantees that both objects are in focus.
We are proposing this as number 1.

According to this proposal, both objects A and B can be brought into focus with the aperture value obtained as above, but on the other hand, the aperture value obtained by the above method is Subjects A and B are highly dependent on the accuracy of the amount of defocus between the lens positions that are in focus, and if this amount of defocus itself contains an error, the calculated aperture may not be accurate. Therefore, it becomes impossible to shoot with both plates A and B in focus.

On the other hand, when moving the lens to the intermediate position, move the lens to the lens position where the autofocus device focuses on subject A, calculate the defocus amount for subject B in this state, and calculate the defocus amount for subject B. The lens is moved to an intermediate position that is internally divided by the amount, and the focus detection error in the focus detection operation in the defocus detection described above and the position control error in the lens drive mechanism that moves the lens to the intermediate position affect the aperture calculation described above. do.

〔the purpose〕

The present invention has been made in view of the above-mentioned matters, and when performing the above-mentioned aperture calculation, an aperture value that is offset by a certain amount toward the aperture side from the calculated aperture value is obtained, and this offset aperture value is used to perform actual aperture control. This offset amount is used to absorb the above-mentioned error and ensure that both objects are always in focus.

〔Example〕

FIG. 1 is a circuit diagram showing an embodiment of a camera equipped with an autofocus device according to the present invention.

In the figure, PR3 is a camera control device, for example, a one-chip microcomputer with internal ROM, RAM, and A/D conversion functions. Performs camera operations such as focus detection function and film winding/rewinding.

Microcomputer PR3 has communication signals So, S
r, 5CLK is used to communicate with peripheral circuits and lenses, and to control the operation of each circuit and lens.

So is the data signal output from PR5, SI is PR3
The data signal 5CLK input to is a synchronization signal of the signals so and sr.

LCM is a lens communication buffer circuit, and when the camera is in operation, the lens power supply V'L is applied to the lens, and the signal CLCM from the microcomputer PR3 is at a high potential level (hereinafter abbreviated as H''; low potential is (abbreviated as L), it serves as a buffer for communication between the camera and the lens.

Microcomputer PR3 sets signal CLCM to H°
When the predetermined data is sent as an SO scratch signal in synchronization with the 5CLK signal, the circuit LCM is designated and the buffer signals LCK and DCL of the 5CLK signal and SO signal are sent to the lens through the camera-lens interface. Output to.

At the same time, the buffered signal of the signal DLC from the lens (the part surrounded by the one-dot chain line) is output as the Sl signal, and the computer PR5 manually inputs the lens data as the Sl signal in synchronization with the 5CLK signal.

SDR is a drive circuit for the line sensor device SNS for focus detection, and is selected when the signal C3DR from the computer PR3 is H', and is switched to SO.

It is controlled by computer PR3 by Sr and SC'LK signals.

The SNS is, for example, a pair of CCD line sensors CCD, C
This is a sensor device including CD2.

φ1. φ2 is clock CK from computer PR3
CCD drive clock generated by the drive circuit SDR, SH is line sensor CCD +, CCD
CLR, a signal that transfers the charges accumulated in 2 to the transfer section
is a clear signal for clearing the accumulated charges in the line sensors CCD + and CCD2, and each of these signals is formed by a drive circuit SDR controlled by a computer PR3.

The output signal O3 of the sensor device SNS is clock φ1. φ2
Sensor CCD that outputs in time series in synchronization with 1. C
It is an image signal accumulated in each picture element of CD2, and CCD,...
Each bit is output to the CCD 2, amplified by the amplifier circuit in the circuit SDR, and then manually inputted to the computer PR3 as an AO3 signal. The computer PR3 inputs the AO3 signal from the analog input terminal, and in synchronization with the CK signal, performs A/D conversion using its internal A/D conversion function, and sequentially stores it at a predetermined address in the RAM.

AGC signal device SN which is the same <SNS output signal
This is the output of the storage control sensor in the S, and is manually input to the circuit SDR to the sensor CCD.

Used for C0D2 accumulation time control. SPC
has a photometric sensor that receives light through the photographic lens.
The output 5spc is input manually to the analog input terminal of computer PR3, and after A/D conversion, automatic exposure control (AE
) used for

DDR is a switch sense and display circuit, which is selected when the signal CDDR from the computer PR3 is H°, and communication with the computer PR3 is controlled by the So, SI, and 5CLK signals. That is, the switch status of the switch group SWS that switches the camera display based on data sent from the computer PR3, and that is turned on and off in conjunction with various operating members including switches sw, , and sw2 that are linked to the release button. to computer PR3.

MDRI and MDR2 are drive circuits for film feeding and shutter charging motors MTRI and MTR2, and signals MIF, MIR, and M2F.

Execute forward/reverse rotation of the motor with M2R.

MGI and MG2 are magnets for starting the movement of the shutter front curtain and rear curtain, respectively, and are energized by the signals SMGI and 5MG2, and the amplification transistors TRI and TR2, and are connected to the computer PR3.
Shutter control is performed by.

Note that the switch sense and display circuit DDR, the motor drive circuits MDR1 and MDR2, and the shutter control are not directly related to the present invention, so detailed explanations thereof will be omitted.

The signal DCL that is manually input to the in-lens control circuit LPR3 in synchronization with the synchronization signal LCK is data of a command from the camera to the lens, and the operation of the lens in response to the command is determined in advance.

The control circuit LPRS analyzes the input command according to a predetermined procedure, and performs focus adjustment and aperture control operations, as well as various lens parameters from the output DLC (open F number, focal length, coefficient of defocus amount vs. extension amount, etc.) Outputs.

The example shows an example of a single lens that is fully extended, and when a focus adjustment command is sent from the camera, a signal is sent to the focus adjustment motor LMTR according to the drive amount and direction sent at the same time. The LMF and LMR are sent out and the motor LMT R is driven to move the optical system in the optical axis direction and perform focus adjustment. The amount of movement of the optical system is monitored by the signal 5ENC of the encoder circuit ENC, and when the predetermined movement is completed, the signals LMF and LMR are set to L' to brake the motor LMTR.

When an aperture control command is sent from the camera, a known stepping motor DMTR linked to the aperture mechanism is driven in accordance with the number of aperture stages sent at the same time. still,
Stepping motors can be controlled open, so
Does not require an encoder to monitor operation.

Note that the circuit LPR3 has a lens focal length of 11! A memory is provided in which the above-mentioned barometers such as tf information (in the case of a zoom lens, focal length information according to the zoom state) are stored at predetermined addresses. Moreover, the circuit LPR
3 is provided with a counter that counts the pulses as the monitor signal 5ENC, and further counts the number of pulses corresponding to the defocus amount when driving the lens, which will be described later, and the count value is calculated from the count value before driving the lens. When the signal corresponding to the defocus amount changes by counting the number of pulses, that is, when the count value changed by lens driving matches the value corresponding to the defocus amount, the signals LMF and LMR are set to L and the motor LMTR It has a control circuit that stops the operation. Furthermore, as described above, this circuit generates a lens stop signal when the motor control stops when the count values match, and also generates a lens stop signal before the change in the count value due to lens driving reaches a value corresponding to the defocus amount. Detects that the drive has stopped,
At this time, a signal forming circuit for forming a lens drive disabling signal is further provided. The lens drive failure signal is generated by determining whether or not the monitor signal 5ENC has not been generated for a predetermined period of time or longer in a state where the change in the count value does not correspond to the defocus amount. A lens drive disabling signal is generated when the lens is not generated for a predetermined period of time under various conditions.

In addition, the above display is for displaying focus and focus detection failure or NG.
LDE for display, and furthermore DEP+ which will be described later.

It is assumed that the device has a display element such as a segment that performs DEP2 display.

The operation of the camera configured as above will be explained using FIG. 2.

When the power switch (not shown) is turned on, power is supplied to the microcomputer PR5, and the computer PR
5 executes the stored program.

FIG. 2(a) is a flowchart showing the entire flow of the above program. When execution of the stored program is started, each step is executed sequentially from step 1.

Step 1: It is determined whether it is Dave's mode or not.

This judgment is made by setting the signal CDDR to H from the computer PRS, designating the circuit DDR, sending an SI signal indicating the setting state of the mode selection switch provided in the manual switch group SWS, and inputting the setting state of the mode selection switch provided in the manual switch group SWS to the computer PR5. This is done by determining the setting state.

If the mode is set to normal mode, step 2
Move to.

Step 2: The state of the switch SW1, which is turned on by operating the shutter button at the first step, is detected.

The state determination operation of the switch SW+ is performed by the switch group SW
This is done in the same manner as S.

When switch SW1 is on, step 3.4 is executed and then the process returns to step 1. When switch SW1 is on, all flags are set to 0 in step 5, and a lens stop command is issued in step 6. After that, go to step 1 again.

Therefore, if the mode is set to normal mode and the shutter button is not operated, steps 1 → 2 →
5 → 6 will be repeated.

Suppose now that the mode is set to depth mode with the shutter button not being operated.

In this case, during the repetition of steps 1→2→5→6, it is detected in step 1 that the mode has shifted to Dave's, so the process goes to step 7 for eight lines.

Step 7: Prohibit release operation.

Step 8: Set all flags except flag DEP to 0 and set flag DEPI to 1.

Step 9: Determine the state of the switch SW1, and if the switch SW1 is off, proceed to step 10 and subsequent steps, and if the switch SW1 is on, proceed to step 17.

Assume that switch SW1 is now off.

In this case, a lens stop command is issued in step 10,
In step 12, the setting state of the flag DEPDN is determined.

Since the flags other than the flag DEP are set to 0 in step 8, the process moves to step 13, and the flags DEPJF and DEPOK are set to 0. In step 14, it is determined whether the setting mode is set again, and the mode remains in Dave's mode. If the depth mode is held, the process moves to step 15, and if the depth mode is canceled, the process moves to step 16. In step 15, it is determined whether the elapsed time of the internal timer exceeds a predetermined value. It is assumed that this timer starts its timekeeping operation after the Dave's mode is set.

If the time measured by the timer has not exceeded the predetermined time, the process goes to step 9 again, and if the time has exceeded the predetermined time, the process goes to step 16.

Unless a predetermined period of time has elapsed after the depth mode is set in steps 9 to 16 above, steps 9 to 16
Step 15 is repeated, and if switch SW1 is turned on within this predetermined time, the step moves to step 17. If the switch SW1 is not turned on within the predetermined time, or if Dave Smote is canceled, the process proceeds to step 16, where all flags are set to 0, and the process returns to step 1 again.

Therefore, even if the Dave's mode is set once, if the shutter button is not operated within a predetermined time, the Dave's mode is canceled and the mode returns to the normal mode.

Now, it is assumed that the shutter button is operated at the first step within a predetermined time after the Dave's mode is set.

In this case, as described above, the process moves to step 17 and the photometry subroutine is executed.

In this photometry subroutine, the output 5spc of the photometry sensor SPC that measures light through the photographic lens is sent to the computer P.
The signal is input to R5, digitized by the internal A/D conversion function, and the digital value is stored in memory.

After the photometry subroutine is performed, the process moves to steps 18 and subsequent steps.

Step 18. The above timer is reset and the timing operation is restarted from the initial state.

Step 19: Detect the set state of flag DEPJF.

Now, in step 8, flags other than the flag DEP are set to 0, so the process moves to step 20.

The AF control subroutine of step 20 is shown in FIG. 2(b).
It is described after step 100.

The first operation of the AF control subroutine in the digis mode will be described below.

Step 200: Detect the set state of flag PRMV. Since this flag is also set to 0, the process moves to step 201.

Step 201: Detect the set state of the flag DEPMV. This flag is also set to O, and the step moves to 204, where it is determined whether the mode is Dave's mode or not. Since the current mode is Dave's mode as described above, the step moves to 205.

Step 205: Detect the set state of the flag DEP. Since the flag DEP was set to 1 in step 8, the step moves to 206.

Step 206 is a focus detection subroutine, which is described after step 300 shown in FIG. 2(Q). Next, this subroutine will be described.

Step 300: Execute the image signal manual subroutine.

In the image signal input subroutine, first the computer PR
In step 5, set C3DR to H, select the drive circuit SDR, and set S
The O double signal is transmitted to the drive circuit SDR. The SO double signal at this time is an accumulation start command, and in response to this command, the drive circuit SD
R transmits the CLR signal to the line sensor device SNS and the CCD
The image accumulation signal of the line sensor is cleared, and then an accumulation operation is performed on the image. CC of line sensor device SNS
Image light beams incident through the photographing lenses are incident on the D line sensors CCD + and CCD2, respectively, and the image position on each sensor CCD+ and CCD2 is determined according to the focal state.

To explain in detail, each sensor CC determines the in-focus state for the subject.
The same image pattern is projected at the same position on DI and CCD2, and in the front bin or rear bin state, CCD + and CCD
The image pattern on 2 is projected at symmetrically shifted positions depending on the direction and amount of focus shift. Therefore, the above C
By detecting the amount and direction of positional deviation between the image patterns on the CD and the CCD 2, the direction and amount of out-of-focus are detected.

After clearing the image signal, the image pattern projected to the position according to the focus state as described above is transferred to each CCD +, CCD.
2 for a predetermined period of time, and then the signal SH and clock φ1. φ2 is supplied to the sensor device SNS.

Note that the accumulation time of the image pattern is determined based on the output AGC of the accumulation control sensor within the SNS.

As described above, the signal SH and the clock φ1. When φ2 is supplied, each sensor CCD from the sensor device SNS and the output end.

The image signals accumulated in each picture element of the CCD 2 are sequentially sent out in time series as an output O3, amplified by an amplification circuit in the drive circuit SDR, and sequentially input to the computer PR3 as a signal AO3. The computer PR3 sequentially converts the signal AO3 into digital values using an internal A/D conversion function and stores them in a predetermined RAM.

With the above operations, the image signal for each sensor corresponding to the image pattern on the sensor CCI)+ and CCD2 is stored in the RAM as a digital value, and the image signal manual subroutine is ended and the process moves to step 301.

Step 301. Executes the defocus amount calculation subroutine. In this subroutine, the amount and direction of deviation in focus are calculated as defocus 1DEF based on the digital values corresponding to the image patterns on the sensor CCD+ and CCD2 obtained in the image signal manual subroutine.

Since the specific method of calculating the defocus amount is not directly related to the present application, a detailed explanation thereof will be omitted, but as mentioned above, the degree of coincidence between the image patterns of the sensors CCDI and CCD is determined by the focus state. The digital values of the respective sensors corresponding to the pattern are compared and processed, and the degree of coincidence of the data is determined to determine the amount and direction of deviation from the in-focus state, that is, the defocus amount DEF.

Also, in this subroutine, the sensor CCD.

The contrast CNT is also determined from the digital value corresponding to the image pattern of the CCD 2, and this contrast detection is also known. A detailed explanation thereof will be omitted.

Step 302: Set flags JF and AFNG to 0.

Step 303: Contrast CNT and constant value LCLV
When CNT<LCLVC, that is, when the contrast is low, the flag AFNG is set to 1 in step 304, the focus detection subroutine is ended, and the process proceeds to step 207.

Further, when CNT>LCLVC, that is, when the contrast is sufficient, the process moves to step 305, and the calculated defocus amount DEF is a constant defocus amount JF that can be regarded as in-focus.
It is determined whether or not it is within FLD, and DEF<JFFLD
In this case, the flag JF is set to 1 in step 306, the focus detection subroutine is ended, and the process proceeds to step 207. Further, when the above judgment shows that DEF>JFFLD, the focus detection subroutine is ended without setting the flag JF to 1, and the process proceeds to step 207.

In the above focus detection subroutine, the flag AFNG is set to 1 when the contrast is low, and the flag JF is set to 1 when the contrast is sufficient and the amount of defocus is considered to be in focus. If the value is larger than the range that can be considered as a fire, return without setting the flag JF to 1.

After the focus state is detected and determined in the focus detection subroutine, a flow routine to be displayed in step 207 is executed. In the blue routine shown below, when the flag AFNG is set to 1, the computer PR3 sets the CDDR signal to H, designates the circuit DDR, and sets the SO
A display signal as a double signal is transmitted to the circuit DDR, and the display signal DS
The LED provided at P for indicating that focus cannot be detected is turned on. Further, when the flag JF is set to 1, the focus display LED is lit in the same manner.

After the focus state is displayed in the display blue routine, the step moves to 208.

Step 208: Determine whether flag JF is set.

Step 2 when flag JF is set to 1
At 09, the set state of the flag DEP is determined.

Now DEP, is set to 1, so step 21
0 and sets the flag DEPJF to 1, then returns and moves to step 9 again.

Further, when the flag JF is O, the set state of the flag AFNG is determined in step 211, and when AFNG is set to 1, the process returns to step 9 again.

Further, when both flags JF and AFNG are O, steps after step 212 are executed.

Step 212. Lens drive amount calculation subroutine (F
This is called the P calculation subroutine. )Execute. This subroutine is described after step 400 shown in FIG. 2(d).

Step 400: Input the "coefficient S of defocus amount vs. projection amount" from the lens. This manual operation sets the signal CLCM to H in the computer PR3, designates the circuit LCM, and designates the circuit LPRS in the lens via the circuit LCM.

Further, the signal SD is transmitted to the circuit LPR3 as DCL via the circuit LCM. The signal SO at this time is a command to read the coefficient S, and the circuit LPR5 transmits the coefficient S stored in the internal RAM as a signal DLC to the circuit LCM by the signal SO, and the circuit LCM reads the signal DLC from sr. Human input to computer PR3 as a signal, coefficient S
is human-powered by a computer.

Step 401: Manually determine the amount of output PTMJ per encoder pulse from the lens. The manual operation of the PTH is performed in the same manner as the coefficient S above.

Step 402: Calculation D of the coefficient S and PTH input in each of the above reading operations and the calculated defocus amount DEF
Perform E F * S/F P H.

As mentioned above, FPH is the amount of output per encoder pulse, and the encoder ENC is composed of, for example, a pulse plate that detects the amount of movement of the lens LNS and outputs one pulse for each unit of movement. ing.

Further, the coefficient S is a coefficient of the amount of defocus versus the amount of projection,
DEF>ks indicates the amount of extension according to the amount of defocus, that is, the amount of movement of the lens according to the amount of defocus. Therefore, DEF)kS/FPH indicates the number of pulses from the encoder ENC according to the defocus amount,
By moving the lens by the number of pulses FP, the lens is driven by the calculated defocus amount.

After determining the number of pulses FP according to the defocus amount in the FP calculation subroutine, the process moves to step 213.

In step 213, a lens drive subroutine is executed. In this subroutine, C
The LCM signal is set to H, the circuit LPR5 is designated as described above, and the pulse number FP is transmitted to the circuit LPR3 as a signal So. In the circuit LPR3, the signal LMF or LMR is set to H according to the above-mentioned FP, and the motor LMTR is driven.

Note that the above FP is determined according to the amount of defocus, and also includes information on the direction of deviation until focusing, that is, the driving direction of the lens, and the signal LMF or LMR changes to H according to this driving direction information. The lens is set and driven in the focusing direction.

After starting the driving of the lens in step 213, the step goes to 214 for eight lines, sets the flag PRMV to 1, ends the AF subroutine, and returns to step 9.

Now, when the above-mentioned focus judgment is made in the above-mentioned first AF control subroutine when the switch SW1 is turned on for the first time in the Digis mode, the process returns to step 9 after the focus is displayed as described above. . In this state, if the switch SW is kept on, step 1 is performed again.
In step 7, a photometry subroutine is performed, and in step 18, the timer is reset, and in step 19, it is determined whether the flag DEPJF is set.

At this time, the flag DEPJF is set to 1, so the step moves to 21 and it is determined whether the flag DEPOK is set. Since the flag DEPOK is set to O in the initial state, the process proceeds to step 22 and subsequent steps.

Therefore, when a focus is suddenly determined in the AF control subroutine during the first turning-on operation of the switch SW1 in the depth mode, the focus is displayed and then the process moves to step 22.

Also, if it is determined that focus cannot be detected when switch SW1 is turned on for the first time in Dave's mode, step 9→17
→18 →19 →20 are repeatedly executed as long as the switch SWl is on, and the focus detection operation is repeated.

Further, even if a lens drive instruction is given based on the amount of defocus until focusing in the AF control subroutine when the switch SW1 is turned on for the first time in the depth mode, the switch SW1 is turned on after the first AF control subroutine is executed. If it is held, repeat steps 9 → 17 → 18 → 19 →
20 is repeated. In the AF control subroutine in step 20 during the repetition of the above steps, since 1 is detected in the flag PRMV detection in step 200, step 202 is executed and it is determined whether or not the lens has stopped.

The operation for determining whether the lens has stopped will be described.

In this embodiment, when driving the lens, the number of pulses FP representing the amount of movement of the lens is input to the circuit LPR3 as described above.
In addition, pulses are sent from the encoder ENC in accordance with the movement of the lens LMS, and the number of pulses from the encoder is counted by a counter in the circuit LPRS, and when it matches the number of manual pulses FP, the circuit LPR3 outputs the signal L.
Control is performed by setting MF and LMR to L and stopping motor LHTR.

It is assumed that the pulses from the encoder are counted up or down depending on the driving direction of the lens. Since the lens drive control is performed in this way, it can be determined in the circuit LPR3 that the number of human pulses FP and the pulses from the encoder match, and that the motor LHTR has been stopped, and in this circuit, the above-mentioned A lens stop signal is generated when lens drive control is not performed.

Therefore, the computer PRS connects the circuit L as described above.
By specifying PR3 and reading out this lens stop signal, it is determined in step 202 whether or not the lens has stopped.

In addition, if the lens hits an infinite point and stops while driving the lens, the number of pulses from the encoder ENC counted by the counter above will be the number of pulses F.
P does not match, and the lens comes to a halt. Therefore, in such a case, even if the counter and the number of pulses FP do not match, the encoder ENC will not generate pulses, and the circuit LPR3 will not generate pulses from the encoder ENC for more than a predetermined time under the above conditions. When it detects that the lens is not in operation, it sets the signals LMF and LMR to L, stops the motor, forms a lens drive disabling signal, and stores this signal in the RAM inside the circuit. During normal operation and abnormal operation. This is used to determine whether the lens has stopped.

If the lens stop signal cannot be detected in step 202, that is, if it is determined that the lens is still in operation, the AF control subroutine is immediately terminated and step 9 is performed again.
Return to

Therefore, while the lens is being driven in accordance with the defocus amount, steps 9→17→18→19→20 (200→202) are repeated as the above-mentioned repeating steps.

In the process of lens driving as described above, the lens driving amount, that is, the number of pulses from the encoder ENC is the number of pulses FP calculated in the above FP calculation subroutine.
When they match, the outputs LMF and LMR are set to L in the circuit LPR3 which detects the coincidence of these pulse numbers, the motor LMTR is stopped, and the lens is driven by the defocus amount. Therefore, when the lens is driven by the amount of defocus while repeating the above steps, it is determined in step 202 that the lens has stopped, so the flag PRMV is set to 0 in step 203, and thereafter, in the same manner as described above, step 204→ 205→206 is executed.

At this time, since the lens has been driven by the amount of defocus as described above, when the focus detection operation is performed in step 206, it is determined that the focus is in focus, and henceforth step 2
Transition from 08 → 209 → 210.

Therefore, when the lens is driven by turning on the switch SW1 for the first time in Dave's mode, the lens will move until the lens or subject is in focus, and once it is in focus, the above focus judgment will be made. Step 2 in the same way as the operation
Move to 2.

Furthermore, since the AF control subroutine described above is repeated even when the focus cannot be detected, when the focus is no longer detected, the lens is driven to the in-focus position, and the process then proceeds to step 22.

Above is the first switch SW in Dave's mode.

To summarize the Dave's processing operation when turned on, the subject is once brought into focus, and after the subject is brought out of focus, the process moves to step 22.

After bringing the subject into focus as described above, the process moves to step 22, and in this step the flag DEP+
The set state of is determined.

Since the flag DEP is set to 1 as described above, step 23 goes to 6 lines.

Step 23: Display DEP+.

This display is displayed when the signal CDDR is set to H on the computer PR5.
, specify the circuit DDR, and DEP as SO multiplied signal.
+The display signal is transmitted to the circuit DDR, and the circuit DDR causes the DEP and display to be performed in the segment in the display device DSP. This will notify the photographer that the first depth process has been completed.

After this, the step moves to 24, and the flag DEP is set to 0.
is set, and DEP2 is set to 1. Thereafter, in step 25, the flag DEPOK is set to 1, and the process returns to step 9.

After this, if the switch SW1 is kept in the on state, the steps shift from 17 to 18 to 19 to 21. At this time, the flag DEPOK has been set to 1 in step 25, so after step 21, the process returns to step 9. Therefore, after the first depth processing is completed, switch SW
As long as + is on, steps 9→17→18→19→21 are repeated, and the lens continues to be held at the initially focused position. From this state, if you release the shutter button and turn off switch SW1, step 9 → 17 →
Instead of repeating steps 18→19→21, the steps move to steps 12 and thereafter. For IA filling after step 12, set the flags DEPJF and DEPOK to 0 as described above, and check if the mode is held in Dave's or switch SW after the first Dave's processing is completed.

It is determined whether a predetermined time has elapsed since the switch was turned off, and if the mode is returned to the normal mode or if the switch SW1 remains off until the predetermined time elapses, the process proceeds to step 1 via step 16. Back, Dave Smote is canceled.

If the mode is held in dibs and the release button is operated again within the above-mentioned time and the switch SW is turned on, the step shifts to 17 again and the second dibs process is started.

The second Daves process will be explained below.

As described above, the process moves to step 17, where the photometry subroutine is executed, and at step 18, the timer is set to restart time measurement, and the process moves to step 19. At this point, since the flag DEPJF has been set to 0 in step 13 while the switch SW1 is off, the AF control subroutine in step 20 is executed following step 19.

In the AF subroutine, step 200 is performed as described above.

At this point, the flag PRMV is set to O, and the step moves from 200 to 201. At this time, since the flag DEPMV is also set to 0, the step moves to 204, where it is determined whether the mote is deep or not, and since the mode is currently set to Dave's, the step moves to 205. Before starting the second Daves process, the flag DEP is set to 0 in step 24 as described above.
is set, the step moves to 215.

Step 215: Determine whether flag DEP2 is set. At this time, since the flag DEP2 was set to 1 in step 24, the step moves to step 216 in FIG. Nji S
The focus state for the subject at the time when Wl is turned on is determined.

When the flag AFNG is set to 1 as a result of this focus state determination, that is, when the contrast is low and focus cannot be detected, this is detected in step 217 and the process proceeds to step 218.

Step 21B: Execute a blue routine to display NG. In this subroutine, the AF control subroutine is ended after the LED for indicating that focus detection is not possible is turned on in the same manner as the display routine described above.

Further, if the flag AFNG is not set to 1 in the focus detection subroutine in step 216, that is, if it is determined that there is sufficient contrast, step 217 is performed.
Next, the process advances to step 219.

Step 219: It is determined whether the defocus amount DEF obtained in the focus detection subroutine is greater than the constant value dc. If IDEFI>dc as a result of this determination, the process moves to step 218, a focus detection failure display is displayed, and the AF control subroutine ends.

Therefore, in the second dibs process, when it is detected that the contrast is low or that the amount of defocus is large, the AF control subroutine is immediately terminated and the process returns to step 9.

If the switch SWI is kept on in the state of 3, the steps will again shift from 9 to 17 to 18 to 19 to 20, and this step will be repeated until the above focus detection results are different. , in the focus detection subroutine, the contrast is sufficiently high and the amount of defocus is l DE
When it is determined that F 1 < dc, step 2
Move to 20.

Incidentally, when it is determined that the focus detection result at the first step 216 is sufficient in contrast and IDEFI<dC, the process immediately proceeds to step 220 without repeating the above focus detection operation.

In addition, in the second depth processing, the reason why Daves processing does not proceed when the defocus amount is more than a predetermined value is when the subject in the first depth processing and the subject in the second processing are extremely far apart. This is because the Daves mode process itself, which brings both liquid objects into focus, is not performed with high accuracy, making processing in Daves mode virtually impossible.

When the process moves to step 220 as described above, step 2
At step 20, the focal length information of the lens is manually entered into the memory LSTFL.

The computer P inputs this focal length information.
The signal CLCM is set to H at R3, and the circuit LC is activated as described above.
This is executed by specifying the circuit LPR3 via M and reading the focal length information stored in the circuit.

Note that if the lens is a zoom lens, focal length information corresponding to its set zoom state will be read out.

After reading the focal length information in step 220 in this manner, the process moves to step 221.

Step 221: From the calculated defocus amount, determine the aperture value that brings both the inner subjects into focus when the first and second Dave's processing is performed.

In other words, as shown in Figure 3, if the lens can be brought into focus when the lens is positioned at DEP for subject A in the first Dave's processing, then in the first depth processing the lens will be in focus at DEP+. moving into position.

In this state, when the second Dave's process is executed for subject B, which will be in focus when the lens is moved to the DEP2 position, the lens position DEP for subject B at the second depth IA filling will be changed. Focus DEF is detected in the focus detection operation, and this defocus amount becomes the defocus amount between lens position DEP and DEP2.

As mentioned above, the Daves processing in the present invention is a position DE that internally divides the defocus distance between two different subjects to the - closest side.
Move the lens 8 to P3, and at this position, DEP3 and D
The value obtained by dividing the defocus amount between EP2, ie, 'DEP1x7' by the circle of least confusion 0.03'5 mm, is adopted as the control aperture.

To explain in detail, the lens is generally DEP as described above.

When positioned at , the subject A and lens become the matching point
If there is a subject B that will be in focus when positioned at 2,
Position DEP, and position DEP 3 that internally divides DEP.
Shift the lens to DEP
By dividing the defocus amount DFF' between 3 and the original focus position DEP for one subject, or DEP2 by the circle of least confusion, the lens can be focused at the original positions DEP+ and DEP2 while keeping it at DEP3. It is possible to obtain an aperture value that satisfies the depth of field so that the two subjects A and B are both in focus.

Therefore, in the present application, utilizing this principle, when the lens is shifted to the D E P 3, the closest object DEP2
We are looking for an aperture that will bring the subject into sufficient focus. In addition, the aperture at this time does not cover the depth within the depth for the position DEP on the infinity side, or considering the characteristics of a normal lens, the aperture does not cover the above depth or originally for the subject on the infinity side. In this application, the internal division point (DEP3) is set at the position of □ on the close side.

In this way, the aperture value 1DEFlx-x- 170,035 that brings both the inner subjects into focus is determined in step 221, and this is stored in the memory LSTFNO.
The process moves to step 222.

Step 222: It is determined whether flag JF is set to 1 as a result of the focus detection subroutine in step 216 above.

As a result, if the flag JF is set to 1, the process moves to step 223, and the flags DEPJF and DEP2 are set to 1.
Set JF to 1 and end the AF control subroutine.

In steps 222 and 223, a subject whose flag JF is set to 1 is detected in the second depth processing is set to the same position as the first depth processing subject, and a subject in the same position is used as the subject of the second depth processing. In other cases, the process moves to step 223.

It is now assumed that the subject positions in the first and second shots are different, and the process moves to step 223.

This step 223 executes the EP calculation subroutine, whereby the number of pulses FP corresponding to the amount of defocus up to the subject in the second Dave's process is determined, and the process moves to steps 224 and subsequent steps.

Step 224: Set flag DEPMV to 1.

Step 225: Input count value FCNT representing the current position of the lens.

As mentioned above, the circuit LPR3 is manually supplied with pulses representing the amount of lens drive from the encoder ENC, and when controlling the drive of the lens, these pulses are counted and matched with the number of pulses FP corresponding to the amount of defocus as described above. We are detecting whether or not it has been done. Therefore, the pulses from the encoder ENC are counted by the circuit LPR3,
This count value is sent to the computer PR5 as a count value FCN representing the current lens position.
Man-powered as T.

Further, the above count value of this circuit LPR3 is specified by the above operation by setting the signal CLCM to H in the computer PR3, and the above count value is requested as the SD signal at this time, and the count value is or signal SL
This is what is input into the computer as.

Step 226. Based on the defocus amount, the lens is driven in the focusing direction in the same manner as in the lens driving subroutine described above. That is, the lens is driven from the lens position determined by the first Daves process by the amount of defocus determined by the second Daves process.

Step 227: The number of pulses FP corresponding to the defocus amount obtained in step 223 is stored in the memory DE.
Manpower PFP.

Step 228: Add the current count value FCNT of the lens manually inputted before lens driving and the number of pulses FP corresponding to the defocus amount input to the memory, and input the result to the memory 5TLPO3.

With this, the position information to which the lens should be moved is set in the memory 5TLPO3.

That is, as shown in FIG. 3, it is assumed that the lens is at the position DEP in the first Dave's process, and the count value at this time is N1. Then, in the case where it is possible to focus on the subject in the second depth processing by moving the lens to position DEP2 in the second depth processing, the lens is driven from DEP+ to DEP2. Assume that the quantity FP is obtained in step 223 above, and N2 is obtained as the number of pulses FP.

In this case, N20N is stored in the memory 5TLPOS. This value N, 10N2 means that the lens is DEP+
When the lens is DE for the above counter value N1 when
It shows the count value when moving from P to DEP2, and is the count value at the target position to which the lens should be moved.

The above step 228 ends the execution number AF control subroutine and returns to step 9.

If the switch SW1 is kept on in this state, steps 17.18°19 are performed following step 9. At this time, assuming that focus has not been determined in the AF control subroutine during the second circle digit processing, step 2
0, and the AF control subroutine is executed again.

In this AF control subroutine again, the flag PRMV is set to 0, and the flag DEPMV is set to 1 in step 224 of the previous AF control subroutine, so the steps are 200 → 201 → 2.
The process moves to step 29, where it is determined whether the lens has stopped or not in the same manner as step 202 described above, and if the lens has not stopped, the process returns.

Therefore, unless the lens is stopped, step 9 above
→17→18→19→20 (200→201→229
) is repeated to confirm that the lens has stopped, and the step moves to 230.

Step 230: This step is the same as step 225 above, and inputs the count value FCNT when the lens is stopped after the second Dave's process.

Therefore, step 223 in the second Daves process is now
If the number of pulses FP found in is N2, the lens will normally be driven until N2 pulses are sent from the encoder ENC, so the count value in this state is the first time before the lens is driven. If the counter's curvature at the lens position DEP+ (Fig. 3) at the end of Dave's processing is N1, then it becomes N, 10N2. After this step, the step moves to 231.

Step 231. Memory 5T found in step 228
The count value representing the current lens position obtained in step 230 is subtracted from the value stored in LPO3. As mentioned above, the value of the memory 5TLPOS represents the scheduled lens position when driving the lens by the defocus amount obtained in the second Dave's process after the first Dave's process, and The count value at the end is N1, and when the pulse corresponding to the amount of defocus from that position is N2, it becomes N, +N. Therefore, the subtraction result becomes zero when the lens is driven by the defocus amount.

Step 232: Detect the lens drive failure signal. This detection operation is performed in the same manner as the lens stop signal detection operation described above.

Now, if it is determined in step 232 that the lens is not stopped because it cannot be driven, then the step moves to 233.

Step 233: It is determined whether the absolute value of the calculation result obtained in step 231 is 4 or more. As described above, if the lens is driven by the defocus amount determined in the second dibs process, the calculation result in step 231 will be zero, but if the lens is not driven by the defocus amount, or if the lens is not driven by the defocus amount, If the lens overruns due to inertia, etc. even if the motor stops after driving for a minute,
The smaller the drive amount is than the planned amount, or the larger the overrun amount, the larger the above calculation result becomes.

Therefore, in this step, when the above calculation result is 4 or less, it is assumed that the defocus amount is driven and the lens has been driven to the scheduled lens position determined in step 228, and the flag DEPMV is set in steps 234 and 235. 0
and sets DEPJF to 1 and ends the AF control subroutine.

Further, in step 233, if the calculation result in step 231 is 4 or more, it is assumed that the lens drive has not yet moved to the scheduled lens position, and step 236
The lens drive instruction is issued again at , and after driving the lens, the process returns to end the AF control subroutine.

Now, in step 233, it is determined that the lens has not been driven to the expected lens position, and step 2
It is assumed that after the lens is driven again in step 36, the AF control subroutine ends and the process moves to step 9.

Assuming that the switch SWI is kept in the on state at this time, steps 17→18→19→20 (200→
Steps 201→229) are executed until the lens stops, and when the lens stops, the steps 230→231→
232→233 is executed again. Therefore, as a result of re-driving, in step 233, the calculation result in step 231 is 4.
If it is determined that the lens has moved to the scheduled position determined in step 228, step 234
, 235 are executed, and in other cases, the above operations are repeatedly executed until it is determined in step 233 that the lens has moved six times to the expected position determined in step 228. Therefore, these steps 200→201→
229 → 230 → 231 → 232 →
In steps 233-236, it is guaranteed that the lens will be reliably moved to the scheduled lens transfer position determined in the second Dave's process. The above operation is an operation when it is determined in step 232 that the lens is not in a drive-incapable state, but in step 232, the lens moves to a limit position such as an infinite position, and the lens cannot be driven. If it is determined that the state is present, step 237 is executed following step 232.

Step 237: In this step, it is determined whether the lens has hit the infinite end position and the lens cannot be driven.

The above judgment method is based on the defocus amount DE as described above.
Since F also includes lens driving direction information, DEF
For example, a positive or negative sign is attached to the pulse number FP calculated based on the driving direction as information representing the driving direction, and by detecting this sign in this step, it can be determined whether or not the lens is being driven toward infinity. A judgment is being made.

In this step, when the lens becomes undriveable while being driven in the infinity direction, when it is determined that the lens immediately hits the infinity end and stops, the step moves to 234, and from then on the above lens drive is performed correctly. It is treated as if

Further, when it is determined in step 237 that the lens driving direction is on the close side, that is, when it is determined that the lens is stopped at the close end, the flag DEP is set in step 238.
, DEF2°DEF3 and DEPDN are set to 0, and in step 239, NG is displayed on the display device DSP, and then the AF subroutine is ended.

Therefore, if the lens hits the close end while driving the lens during the second Daves processing and the lens cannot be driven, that is, if the desired image cannot be taken even after depth processing, further depth processing is necessary. Do not do the above NG
The display notifies the photographer that depth processing is not possible, and instructs the photographer to redo depth processing from the beginning.

The reason why it is assumed that the lens is driven normally during the second depth processing when the lens is stopped at the infinity end is that there is no infinite state beyond the infinity end for the lens; Even if you cancel the Daves processing and redo the Daves processing again, no further improvement can be expected. This is to allow the subsequent depth processing to continue.

In addition, the reason why the lens is controlled by servo (close loop) to the scheduled position when driving the lens in the second depth processing is that in the depth mode of this application, the lens is moved to the lens position determined in the second Daves processing. After that, the position where the defocus amount obtained in the second Daves process is internally divided into - or - is calculated from this position, and the lens is moved to the above internally divided position, so the second depth This is because the lens position during processing must be accurately driven by the above defocus amount.

Also, since the lens is servo-controlled in the second depth process, even if switch SW1 is turned off while the lens is being driven in the second depth process, the lens will always be moved to the correct lens position. I can do it. That is, 2
switch s while driving the lens in the second depth processing.
When W1 turns off, the process moves from step 9 to step 10, at which point the lens stops. Also, after this switch SW1
While it is off, steps 9 to 15 are repeated, and when switch SW1 is turned on again, steps are 7 → 17 → 18 → 1.
Transition from 9 to 20.

At this time, the flag DEPMV is kept set to 1, and when the switch SW1 is turned on again, the process moves to step 20. When the AF control subroutine is executed, the process goes to steps 200→201→229→230 in 8 lines. Then the above process is restarted. It is assumed that the lens stop signal is also generated when the lens is stopped by the lens stop command in step 10. Therefore, the process proceeds to step 230 after the switch SW1 is turned on again, and in this step a count value representing the lens position (SW, lens stop position when off) is input as FCNT, and that position and step 228 are calculated. The lens is moved as described above by the difference from the scheduled position. Therefore, even if switch SW1 is accidentally turned off while moving the lens during the second Dave's process, if switch SW1 is turned on again, the lens drive process to the scheduled position will be restarted, and the lens will always move to the correct lens position. I will do it.

When the lens moves to the scheduled position through the above operations, steps 234 and 235 are performed as described above, the AF subroutine is ended, and the process moves to step 9.

If the switch S W + is on in this state, the steps shift from 9 to 17 to 18 to 19.

At this time, since the flag DEPJF is set to 1 in step 235, the step proceeds to 19-21, and since the flag DEPOK is set to 0 at this time, the step proceeds from 21 to 22. Also, at this time, the flags DEP+ and DEP2 were set to DEP, = O, DEP2 = 1 in the above-mentioned step 24 during the second Dave's processing B line, so the steps are 22 → 26 → 27 →
28, the display device DSP displays DEP2 indicating that the second depth processing has been completed, and the flag DE
Set P2 to 0 and DEP3 to 1, step 25
Set flag DEPOK to 1 at step 9 again.
Move to.

If the switch S W + is kept on in this state, steps 9 → 17 → 18 → 19 → 21 → 9 will be repeated, and the lens will be held at the position determined by the second Daves process. Thus, the second Daves process is completed.

After this, turn off the switch SWI and turn the switch SW + again.
When turned on, the steps shift from 9 to 17 to 18-19. At this time, the switch SW1 has been turned off as described above, so the processing in step 13 has been carried out, and the flag DEDJF is set.

DEDOK is set to O. Therefore, the process goes from step 19 to line 20 for eight lines, and executes the AF system control subroutine again.

Incidentally, at this point, the flag DE is set in step 234 above.
Since PMV is set to 0, the AFF control subroutine moves to steps 200 → 201 → 204 → 205, and the flag DEP is set at step 24.28 above.
=0゜DEP2=O,DEP3=1
Since it is set to , the process moves from step 205 to step 240 after step 205, and step 240 is executed.

Step 240: Determine the state of flag DEP2JF. This flag is set to 1 only when step 223 is executed during the second depth processing, that is, when the subjects are at approximately the same position during the first and second depth processing.

Therefore, if the first and second Dave's processes have been performed on subjects at different positions, the process moves to step 241.

It is assumed that the step has now moved to 241.

At step 241 and step 227, the memory DEPF is
The number of pulses FP manually applied to P, that is, the number of pulses corresponding to the amount of defocus up to the lens transition position obtained during the second deiras process, and the number of pulses when the lens is driven to the planned position in steps 233 to 235 above. The pulse number obtained in step 231 is subtracted. That is, for example, as shown in FIG. 3, if the count value representing the lens position DEP during the first depth processing is N1, and the number of pulses FP corresponding to the defocus amount during the second depth processing is N2, then
The count value representing the lens transition position DEP2 scheduled for the second depth processing determined in step 228 is N, +N2.

Also, in steps 230 to 236, as described above, the lens is driven until the scheduled lens position and the current position of the lens are within 4 pulses, so the count value representing the lens position DEP2 actually shifted in the second Daves process is As shown in FIG. 4, <Nl+N2±α, 4≧α≧−4, and there is an error within ±α from the planned lens position.

Then, in the above step 231, the planned position (Nl + N
2)-Lens transition position (N, 10N2±α) is performed, and this ±α is found.

Therefore, in this step 241, the number of pulses N2 corresponding to the defocus amount obtained in the first Daves process is subtracted from the above ±α, so that the lens position DEP+ after the first Daves process is 2 Actual lens position hypermotion amount N2 between the actual lens position after the second Daves processing
±α is determined and manually entered into the memory DEP2FP.

Since the distance between the actual lens positions DEP and DEP2 is calculated in this way, even when the lens is stopped at the infinite end as described above, the actual lens position DEP and DEP2 can be accurately determined.
This means that the amount of movement between DEP2 and DEP2 can be detected.

After the amount of movement of the lens position of DEP and DEP2 is determined in step 241, the DEP determined in the second depth processing is determined in step 242.

The sign of the defocus amount DEF from to DEP2 is determined. As described above, the defocus amount DEF also includes information representing its driving direction, and by determining the sign of the defocus amount DEF, the direction of movement from position DEP to position DEP2 is determined. In this embodiment, a positive sign indicates the driving direction toward the closest side, and a negative sign indicates the driving direction toward the infinite side.

Assuming that the current lens position is in the relationship shown in Figure 4, the lens is driven in the close-up direction when moving from DEP to DEP2, so the defocus amount DEF is positive.
At this time, the process moves to step 243.

Step 243: DEP obtained in step 241 above
, and DEP2 is divided internally into m-.

As a result, the number of pulses corresponding to the amount of movement from DEP2 to DEP3 is determined as shown in FIG.

Further, when it is detected in step 242 that the drive is in the infinite direction, step 2 is executed instead of step 243.
44 is executed.

In such a state, the relationship between DEp and DEP2 is as shown in FIG.

Therefore, in step 244, between DEP and DEP2 -
The number of pulses divided internally into DEP2 and DEP3 is calculated, and this number of pulses becomes the number of pulses representing the amount of lens movement from DEP2 to DEP3.

By doing this, the lens position DEP is divided into 7 on the near side and 10 on the infinity side even if the lens is driven in either the near or infinity direction during the second dibs process.
The number of moving pulses can be found from DEP2 to 3,
It becomes possible to shift to the lens position DEP3 of the present application described above.

In this way, step 243. Or at position DEP2 at 244
After determining the number of pulses from the encoder necessary to shift from to DEP3, the process proceeds to 224 and subsequent steps.

Therefore, after this, the lens is driven in steps 243 and 244 in the same way as the lens driving during the second dilas process.
Steps 234 and 235 move from the position DEP2 to the position DEP3 by the number of pulses determined in step 234 and 235.
Then the flag DEPMV is 0 again D E P J F
ni1 h<se':/ Tosa hru.

That is, in step 227 executed in the third dibs process, the above step 2 is stored in the memory DEPFP.
43,244 from position DEP2 to DEP3
In step 228, DE
The count value representing the lens position of P3 is stored in memory 5TL.
It will be stored in PO3.

Therefore, after performing step 244 or 243, the steps 224 to 228 described above are executed, and the process proceeds to step 9. From then on, as long as the switch SW1 is kept on, the lens drive for the second dibs process is performed. Similar steps 9→17→18→19→20 (200→201→
229) or 20 (200→201→229→230
→231→232→233→236) or 20 (20
0→201→229→230→231→232→237
) is repeatedly executed and the lens is driven until it reaches a count position within ±4 of the count value (position of DEP3) stored in the memory 5TLPO3, and the lens moves to a position within the range of ±4 pulses with respect to DEP3. Then, the flag DEP is set in steps 234 and 235 as described above.
MV is set to 0 and D E P J F Ml is set to 3.
Lens driving in the third Daves process is completed.

It should be noted that even when driving the lens during the third digit processing, servo (close) control is used to reach the scheduled lens position.
Even if switch SW1 is turned off once while the lens is being driven, the lens will be driven to the planned position, and if the lens moves to the closest limit position and cannot be driven, depth processing will not proceed and the process will be rejected. Display is performed, and when the lens stops at an infinite position, the lens is held at that position and subsequent Daves processing is performed.

After completing the lens drive in the third Daves process in this way, the steps progress from 9 to 17 to 18 to 19, and 19
1 of the flag DEPJF is detected and the step proceeds to step 21 and thereafter, and the flags DEPOK, DEP, DE
The set state of P2°DEF3 is detected. At this point, the flags DEPOK, DEP, , DEP2 . Since DEP is set to 0 and DEP is set to 1, the process advances to steps 21→22→26→29→30. Step 30
Then set flag DEP3 to 0 and set DEPDN to 1.
is set, and then the program proceeds to step 31 to execute the DAV calculation subroutine shown in FIG. 2(f).

In the DAV calculation subroutine, step 500 is first executed.

Step 500: Lens focal length information or memory NW
Manpower will be provided to FL. Detection of this focal length information is performed in the same manner as step 220 described above.

During the first Daves processing determined in Step 501 and Step 221, the lens is moved to DEP to bring the subject into focus, and during the second Daisy processing, the lens is moved to EP2 for 8 lines to bring it into focus. The aperture value that guarantees the depth of focus for both subject B, that is, the memory LSTF in step 221.
The aperture value manually entered in NO (referred to as LSTFNOAV), the focal length information stored in the memory LSTFL (referred to as f+), and the focal length information stored in the memory NWFL (referred to as f). Operation LST with
FNOAV.

This calculation is performed in order to be able to supply an aperture depth that keeps both liquid photographic objects in focus even if the zoom ratio of the lens is varied during the Daves process and the focal length information changes.

The above aperture value LSTFNOAV is a value obtained based on the amount of defocus when the focal length is f, while the amount of defocus is 4 when the focal length is doubled due to the relationship with the focal length.
It has the characteristic of fold change.

That is, the focal length is 1! Lens position DEP in l1ff+ state.

If the defocus amount when the focus is detected is DEF, then it becomes 4DEF, which is the defocus amount when the same subject is detected at a focal length of 2 f, and the above aperture value LSTFNOAV also becomes 4 when the focal length changes twice. Change twice.

Therefore, when the focal length at which the aperture value LSTFNOAV was calculated and the focal length at the time of shooting change due to zoom operation, etc., even if the aperture is controlled using the aperture value LSTFNOAV, both liquid objects will remain in focus. depth cannot be guaranteed.

Control aperture value AVdep and no, focal length is LSTFN
When the aperture changes twice compared to when the OAV was determined, the aperture is changed four times, and an aperture value that guarantees that both liquid photographic objects are always in focus is determined regardless of zoom operations.

Following this step 501, the step proceeds to 502.

Step 502: In this step, it is determined whether the lens attached to the camera is a zoom lens or a fixed focus lens.

This discrimination operation is carried out by the computer PR3 using the circuit LPR in the same way as the above-mentioned transmission of the focal length information from the lens to the camera.
3, the zoom lens information or fixed focus lens information stored in the RAM in the circuit is read out and manually inputted to the computer PR3, and the above judgment is made based on this manually inputted information. Note that since the zoom lens or fixed focus lens information is determined for each lens, the zoom lens information for the zoom lens and the fixed focus lens information for the fixed focus lens are stored in the RAM of the lens.

If it is determined in this step that the attached lens is a zoom lens, step 503 is executed and a constant value AV7M is added to the aperture value AVdep to determine a correction control aperture value AVdep'. This constant value AV2
By adding M, the aperture value is the above calculated aperture value A.
The aperture value is a little closer to the stop-down side than Vdep, that is, the aperture value is deeper.

This addition process is for absorbing the error with respect to the calculated aperture value AVdep. That is, in determining the above-mentioned AVdep, even if there are various error factors, the above-mentioned error is corrected by setting the actual control aperture to a deeper aperture value.

Further, if it is determined in step 502 that a fixed focus lens is attached, step 504 is executed instead of step 503.

In this step 504, a constant value AVSNG is added to the aperture value AVdep, and the correction control aperture value AVdep' is
I'm looking for. This addition process also has the purpose of error correction similar to that of the zoom lens described above.

Note that the constant value has a relationship of A VSNG <A VZM. The reason why AVSNG and AV2M are set in this relationship is to increase the amount of correction for zoom lenses because they include more error factors than fixed focus lenses.

After determining the correction control aperture AVdep' in the above step, the step moves to 505.

Step 505: Find an integer J that satisfies.

J is twice the apex value, and this J can be used to obtain the aperture value.

That is, the above formula (1) is a modified formula, and in order to find J that exactly corresponds to AVdep', (2;i)' = AVdep' ・
= J can be found using (3). In this case, J is a value that includes not only integers but also decimals, and if J is calculated using equation (1) based on equation (2) above, the decimal part of J obtained using equation (3) above will be rounded up. .

Therefore, the aperture value J obtained using formula (1) is a value that is rounded up according to the AV accuracy, indicating an aperture value on the narrower side,
This step process further performs correction for error absorption.

Thereafter, the process moves to step 506, where J obtained in step 506 is converted into a real number of aperture value.

In addition to the above-mentioned purpose of error absorption, the process in step 505 is to match the mechanical control stage number of the aperture of the camera, and since the aperture value of one stage of the apex is obtained, the mechanical control stage number of the camera is determined. It becomes possible to use it.

When the DAV calculation subroutine is completed as described above, the process moves to step 32, where a DAV display routine is executed. This subroutine is a routine for displaying the real number of apertures obtained in the DAV calculation subroutine on the display device DSP, and its display operation is performed in the same manner as described above.

Moreover, when step 32 is performed, the process moves to step 33 to allow the release operation, and the process moves to step 25 to set the flag DE.
Set POK to 1 and return to step 9. Therefore, if switch SW1 is kept on in this state,
Thereafter, steps 9→17→18→19-21 are repeated. Also, even if the switch SW1 is turned off in this state, the steps 9→10→12→14→15 are repeated, and even if the switch SW1 is turned on again, the steps 9→17 are repeated.
→ 18 → 19 → 21 is repeated. Therefore, even if the switch SW1 is accidentally turned off after all Daves processing is completed, the Daves processing results will be maintained as they are.

When the second step of the shutter button is operated in this state, the release operation processing in the AE control subroutine of step 3 is performed in the interrupt processing, and a signal corresponding to the aperture value J obtained by the above calculation is sent to the computer PR3. S.O.
The doubled signal is transmitted to the circuit LPR3 via the circuit LCM,
The step motor DMTR is driven, the aperture linked to the motor is narrowed down according to the above J, and the shutter release operation is performed, and the shutter time at that time is the photometric value in step 17 and the aperture value determined by the above J. The shutter value is determined based on the shutter value.

With the above operation, depth mode moves subjects at different positions to the close side.7. The lens is set at a focus position that is divided into 10 points on the infinity side, and the aperture is set to a depth that ensures that both wave objects are in focus.

In addition, in the second and third Daves processing mentioned above, 2
The actual driving amount of the lens is determined based on the number of pulses determined according to the defocus amount determined in the second Daves processing, and the lens is driven by this actual driving amount, so the zoom ratio is changed during the digis. Even if the lens hits the infinite end, the lens can be accurately moved to the B line at the - internal dividing point of the double-wave object as described above.

In addition, in Dave Smote, transition to 7 release operation by turning on switch SW2 is prohibited until the third Dave process is completed, so even if you accidentally operate the second release button during Digis mode, it will not work. Subsequent Dave's processing can be executed, and even if the shutter button is erroneously operated until the Dave's mode ends, the mode is maintained.

In addition, in the embodiment, the counter that counts the pulses from the encoder ENC counts up and down the input pulse, and always shows a value that represents the lens position after the lens is driven.Furthermore, when driving the lens for the defocus amount, Although the lens drive amount is controlled to become the defocus amount by determining whether the change in the count value from the count value has become a value corresponding to the defocus amount, there are other ways to control the lens drive amount. Drive amount control may also be performed.

Further, a limit switch may be provided at each limit end as a method of detecting when the lens hits the infinite end or the closest end position.

Also, a method for determining whether or not the lens will hit the limit edge when the lens is driven based on the second defocus amount is to use the calculated defocus amount, the current lens position, and the distance to the lens limit edge. In this case, it is necessary to detect absolute value information from the lens as the current position information of the lens.

〔effect〕

As described above, in the present invention, since the calculation aperture AVdep is offset by a certain amount (AV!ING, AVZN) toward the aperture, the error included in the calculation aperture can be absorbed by the offset. This allows photographing with two different subjects always in focus.

[Brief explanation of the drawing]

1 is a circuit diagram showing an embodiment of the camera of the present invention; FIGS. 2(a) to 2(f) are explanatory diagrams showing programs built in the computer PR3 of the embodiment of FIG. 1; 3, 4, and 5 are explanatory diagrams for explaining the operation of the embodiment shown in FIG. 1. PR5-----------Computer L RR
S -1---Control circuit L CM------1---Buffer circuit D M T R------1-
-Aperture control motor patent applicant Canon Co., Ltd.←−−−−−−−−−−□−+ N2

Claims (2)

[Claims] (1) With the lens stopped at the first position, the focus detection circuit determines the defocus amount for the subject, calculates the aperture value determined by the defocus amount and the circle of least confusion, and Aperture control is performed based on the value, and the lens is moved to a position that internally divides the defocus amount based on the defocus amount. With the lens stopped at the first position, the subject to be in focus and the second In a camera having an automatic focus adjustment device that brings a subject into focus when the lens is driven by the above defocus amount from position 1, a predetermined offset amount with respect to the calculated aperture value. A camera having an automatic focus adjustment device, characterized in that a correction means for shifting the aperture value to a value on the aperture side is provided, and the aperture control is performed based on the aperture value shifted by the correction means. (2) The camera includes a determining means for determining whether the attached lens is a zoom lens or a fixed focus lens, and a first offset amount when the determining means determines that the lens is a zoom lens. supplying the value of to the correction means,
In addition, when it is determined that the lens is a fixed focus lens, the first
A camera having an automatic focus adjustment device according to claim 1, further comprising an offset amount supplying means for supplying a second value smaller than the value of , as the offset amount to the correction means.