JPS63259523A - Camera equipped with focus detecting device - Google Patents

Abstract

PURPOSE:To attain the release of a shutter even if the detection of focus is impossible or the quantity of defocusing is large in a consecutive photographing mode by permitting the release without executing the adjustment of a lens when the detection of focus is impossible or the quantity of defocusing is large at current photographing time and focusing is obtained at previous releasing time. CONSTITUTION:When it is decided that the delay in following occurs to an object based on the quantities of defocusing D5 and D6 at the point P1 in the midst of stopping the lens, the correction of following is executed at the point P1 by means of the computation C6 at the time of integration I6 and the correction is executed at the point P1 by supposing the movement of the object from the integration I6 to the middle point of the integration I8 through the integration I7. But, if a driving counted value to which a correction value is added in the midst of a following mode is larger than a previously specified counted value, the correction in following is not executed, if it overtakes on the way and a driving direction is inverted based on the computed result. Thus, in the consecutive photographing mode even when a camera is in an AF preferential mode, the release of the shutter can be possible even if focusing is not completed.

Description

[Detailed description of the invention] Industrial applications The present invention relates to a camera equipped with a focus detection device.

Conventional technology and its problems For example, in AF-priority cameras, when shooting moving subjects in succession, such as in sports photography, it is not possible to release the shirt until automatic focus adjustment (hereinafter referred to as AP) has been completed. , the camera cannot be released unless it is in focus, so if the subject shifts even slightly from the frame, it will not be possible to take a picture. However, in quick shooting mode, the shooting cycle is fast, for example, if the shooting rate is 3 frames per second, each frame shoots at 30 frames.
It is about 0ff18ec. No matter how fast the subject moves laterally, it may move out of the focus detection area during this 300 m5ec, but it rarely moves out of the shooting area. Therefore, it is unreasonable to be unable to release the shutter even though the subject you want to photograph can be photographed. However, conventional AP-priority cameras have the disadvantage that they cannot release the shutter release when there is an out-of-focus situation, even though it is possible to take pictures as described above.

Therefore, the present invention provides an AP priority mode camera or a camera in which the shooting mode is set to AP priority mode, which is capable of shutter release even if focus cannot be detected in continuous shooting mode and the amount of defocus is large. The purpose is to

Means for Solving the Problems In order to achieve the above-mentioned object, the camera of the present invention includes a focus detection means for calculating and detecting a focus position, a means for setting a lens to a focus position according to the calculation result, and a release release. A control means that repeatedly executes a shooting operation and an automatic focus adjustment operation at a predetermined cycle while the button is continuously pressed, and a control means that repeatedly performs a shooting operation and an automatic focus adjustment operation at a predetermined cycle while the button is continuously pressed, and a control means that repeatedly performs a shooting operation and an automatic focus adjustment operation at a predetermined period. In a camera equipped with automatic focus priority control means that controls the automatic focus priority control so as not to enter operation, when the snapshot mode is set, the result of the focus detection calculation performed by the focus point detection means is that focus detection is impossible or the amount of defocus is insufficient. out-of-focus detection means for detecting that the
A storage means that remembers that the camera was in focus the last time the camera was released, and a lens that adjusts the lens if it is impossible to detect focus or there is a large amount of defocus at the time of the current shooting, and the lens was in focus at the time of the previous release. The present invention is characterized by comprising a means for permitting the shutter release.

According to the above configuration, even if the camera is in the AF priority mode, shirt release is possible in the continuous shooting mode even if focusing is not completed.

Therefore, when several subjects enter the shooting frame in succession, it is possible to take pictures even if the subject behind them is slightly out of focus, and the picture can be taken as intended by the shooting stand. We can provide cameras.

Example FIG. 28 is a graph for detailed explanation of the present invention,
The meanings of the vertical and horizontal axes are the same as in FIG. 27. At time P1 while the lens is stopped, the defocus amount D5. If it is determined that there is a tracking delay for the subject based on D e, tracking correction is applied at point P by calculation C6 at the time of integration 16, and the lens is not stopped at Q, but is adjusted to 9 of the correction qWR. Move the lens further until it reaches Q. This correction 11WR will be described later, but the amount of movement when the subject moves in the direction of the optical axis of the photographing lens of the camera is taken as the amount of defocus in the film of the camera.

This amount of movement is calculated in advance by converting it into an inclination per unit period TI of focus detection. In the case of FIG. 29, the next lens driving time is considered to be TI, and it is assumed that the lens will catch up after the time TI at the latest. If the speed of the subject exceeds the correction amount WR at this time TI, there will be a delay in tracking the speed of the subject, but unless the subject is particularly fast, the taking lens will be within the range where it can be determined that it is in focus. By saying that the camera is catching up with the subject, it can be said that the camera is catching up with the subject. In addition, in this model, it is assumed that the movement of the subject is a linear function of the amount of defocus on the film plane, but in reality, for example, when a subject approaches the camera at a constant speed, the amount of defocus changes. The change in is not a linear function but a higher order function. In this case too,
Even with tracking correction, the amount of correction is insufficient, but since it is within the in-focus range, it can be said that tracking is being achieved. Note that the target correction position in the case of FIG. 28 is the midpoint P3 of the integral (2) 8.

Midpoint P of integral ■8. Since the lens is not moved from to the end point P1 of calculation C6, there is a delay in tracking the subject during this period as well. This delay must be taken into account as well as the delay during the next lens drive (during which period there is one cycle of integration and calculation).

That is, when the subject moves and a tracking delay occurs while the lens is stopped, integrate from integral I8 through integral (2)7 (predicting the movement of the subject to the midpoint of 8 and P).

It is necessary to make corrections at this point. That is, in this case,
This means that it is sufficient to add a 2WR correction using Pl.

The midpoint of this target integral ■ is, from the point of view of P,
The color tone is almost the same as aiming at the time point P when the result of the next integral I7 is obtained. This is because the integration time is short here, so it is assumed that P 2 #P 3. Here, the calculation takes 50 m5ec, whereas the integration takes several m5ec or less.

FIG. 29 shows a case where it is determined that there is a delay in tracking the subject based on the defocus amounts of D and D4 at time P4 while the lens is being driven.

Furthermore, it shows the state in which the lens is being driven with tracking correction continuously applied while chasing a subject in tracking mode, including when it is determined to enter tracking mode while the camera is stopped. . When the tracking mode is entered at time P4 and correction is applied, the lens is driven by the amount of defocus calculated based on the data obtained from the integral ■, and even after driving is completed, the lens is not stopped at Q, and the lens is further 2WR. Move minutes. Second
Similarly to FIG. 8, the correction target time point is the midpoint of the integral I7 near P6 where the result of the calculation based on the data of the next integral 18 is found. This corresponds to exactly two periods of the focus detection calculation from the midpoint of the integral I4 at which the tracking delay was detected. This is an attempt to perform correction drive for a total of two cycles, including the one cycle required to produce the current detection result, within one cycle of producing the next result. The same process is repeated below, but if this lens drive cannot catch up, that is, if the drive count value with the correction value added during tracking mode is greater than the count value determined by Moe, the lens drive speed is switched. . In the figure, the switch is made at Q. Even if the driving speed is changed, the correction value and target value are considered to be the same. If the vehicle catches up with the vehicle midway through and the drive direction is reversed based on the calculation result, the follow-up correction is not performed.

Next, a method for determining the inclination per unit period TI of focus detection with respect to movement of the subject in the camera optical axis direction will be explained using FIG.

In the figure, the unit focus detection period is S, ~S
t, Ss~S4 or T1~T8. T 1~
T3' etc. These images are continuous, and each time is considered to be the same, assuming that the same subject is being viewed. Let the current position be calculation C1. Let the defocus amount found by the previous integration be LERR.

Note that this is found at time T. Let ERR be the defocus amount found by this integration. This is determined at the time of T3°.

From the figure, the defocus amount corresponding to the amount of movement of the subject per unit period, that is, the tilt WR, is WR = ERR + I
It is determined as TI - LERR. Here, ITI is the amount of lens movement from the previous integration to the current integration.

The relative position of the lens at the center of the previous integration is the integration start time T.
1 and the end time T, the sum of the relative positions of the lenses! /2. These T I and T t are values that are converted from the defocus 11LERR' at the time of Sl into a lens drive count number in the calculation C1 and set in the event counter. On the other hand, a focusing encoder is set on the lens, and when the lens moves, a pulse is output from the encoder. This signal is connected to the input of an event counter, and the event counter counts down each time a pulse occurs. Therefore, the amount by which the lens has moved can be determined by reading the value of this event counter. These values are T + and T *. Therefore,
('r l+ T 2)/2=M [L determines the previous center.

Next, use Figure 31 to enter this follow mode and AFL
The case where the shutter is released while the camera is in the camera will be explained. In the present invention, the lens is driven even during the release time lag in order to improve tracking performance. That is, the lens is driven even while the reflex mirror of a negative-eye reflex camera is being raised, for example, from when the release signal is input until the exposure operation is started.

However, since the mirror is raised during this time, focus detection (WR component and calculation) cannot be performed using a focus detection method that detects focus by receiving light through the mirror. Therefore, the distance WS in which the subject moves while the mirror is rising is calculated in advance. If this release time lag time is RTS, then from the subject movement WR per unit focus detection time TI, WS = WRXI (TS/TI). Using this WS as the tracking correction amount, the lens stops after moving to the exposure operation plane. After the film is exposed, the mirror begins to descend, and at the same time, the film automatically winds up and the shutter takes off. (It is not necessary for automatic winding to occur.) At this time, it is assumed that the camera is in a release priority mode that prioritizes the release of the camera over reaching the in-focus state, and the shutter is released before the camera is in focus.

Naturally, the result will be a blurry photo, but if the camera is in continuous shooting mode, you want the second and subsequent photos to be as close to focus as possible. Therefore, while the mirror is lowering (during this period, integration and calculation cannot be restarted until the mirror is stabilized in the lowered position), the lens is driven by the amount that did not reach the in-focus state during exposure before resuming integration. . In the figure, the lens is stopped when the integration is resumed, but there is no problem even if the lens is kept moving.

FIG. 1 is a block diagram of a camera control circuit used in an embodiment of the present invention. (1) is a microcomputer (hereinafter referred to as microcomputer) that performs camera sequence control and calculations, and (2) opens and closes the shutter in response to exposure start and end signals from microcomputer (1), as well as mirror-up signals. An exposure control circuit (3) performs mirror-up and aperture control according to the subject brightness, and a photometry circuit (3) digitizes a signal corresponding to the subject brightness and sends it to the microcomputer (1). (4
) is an automatic film sensitivity reading circuit that digitizes film sensitivity information and sends it to the microcomputer (1). (5)
is a one-frame winding circuit that drives the motor in response to a signal from the microcomputer (1) and winds the film one frame, and -
The motor drive is stopped by turning on the piece winding detection switch (C9). (6) is a setting circuit that sets the aperture value and shutter speed, (7) is the ON of the switch (Sl),
The pulse generation circuit (8) is an interface circuit installed between the C0D (9) used for focus detection and the microcomputer (1), which generates one pulse each in conjunction with the OFF state. Due to the signal of C0D(9)
It controls the start and end of charge accumulation, A/D conversion of data on C0D (9), and output to the microcomputer (1).

(10) is a motor control circuit that controls a motor (M) that drives a focusing optical system of a photographic lens (not shown) for focus adjustment based on a signal from the microcomputer (1);
11) is an encoder that monitors the rotation of the motor (M), and is designed to generate 16 pulses each time the motor (M) rotates once. (12) is a lens circuit provided in the photographic lens, which sends data unique to each lens to the microcomputer (1). (13) is an auxiliary light emitting device used during focus detection. (!4) is a display circuit that displays the focus detection state, and (15) is a timer that generates a release signal at fixed time intervals during a continuous shooting mode in which photography is continuously repeated. (E) is the power battery, and the microcomputer (1
), a switch, a reset resistor (RR) and a capacitor (OR), and a power supply transistor (Tr+), which will be described later, are directly supplied with power. Other circuits are supplied with battery voltage via a power supply transistor (Trυ).

Next, I will explain the switch. (Sl) is ONL and microcomputer (1) at the first stroke of pressing the release button (not shown).
When this switch (Sl) is turned ON or the release button is released, a flow (AFS) to be described later is executed. (C2) is turned ON when the release button is pressed down to the second stroke, which is longer than the first stroke, and this ON causes the microcomputer (1) to execute the release flow shown in FIG. 16(a), which will be described later. (C3) is a switch that is turned ON when the mirror is raised up, and when a release member (not shown) is charged by winding up the film by the frame winding mechanism, the switch (C3) is turned OFF. (C4)
This is a switch that selects between the so-called one-shot mode, in which focus detection operations are stopped once the photographic lens reaches the in-focus state, and the so-called continuous mode, in which focus detection continues even after the photographic lens reaches the in-focus state. It is. (C5) is an exposure mode setting switch, and depending on the set mode, a 2-bit signal is sent to the microcomputer (1). The exposure control modes that the camera of this embodiment has are program mode (hereinafter referred to as P mode), aperture priority mode (hereinafter referred to as A mode), speed priority mode (hereinafter referred to as S mode), and manual mode (hereinafter referred to as M mode). There are four types.

(S6) is a switch for switching between a release priority mode that prioritizes shirt release regardless of the focus state and a focus priority mode (hereinafter referred to as AF' priority mode) that allows or prohibits release depending on the focus state;
S7) is an end detection switch that detects that the lens driven during focus detection has recently been driven to the farthest or infinity focusing position, and this switch (S7) is ON.
By doing so, the microcomputer (1) executes the termination processing flow described below. (S8) is a changeover switch for switching between continuous shooting mode and single frame shooting mode, and (S9) is a one-frame winding detection switch that turns ON when exposure is completed and turns OFF when frame winding is completed.

In the above circuit configuration, when a battery is installed in the camera, power is supplied to the reset resistor (RR) and capacitor (CR), and the reset terminal (RE
) is manually inputted with a signal that changes from "Low" level to "High" level, and the microcomputer (1) executes the reset routine (RESET) shown in FIG.

The microcomputer (1) first resets the flag and output port to the initial state (#5, #10). Next, turn off the auxiliary light emitting device (13), turn off the display, stop driving the lens, drive the motor when film winding is not completed, and when film winding is completed, power supply transistor (Tr, ) (#15 to #30)
. Then, the auxiliary light flag (auxiliary light F
), the terminal (OF2) is set to "Low" level, and the microcontroller (1) stops (#35.#40)
. The above steps #15 to #40 are mainly effective when proceeding from step #55, which will be described later.

When the release button is pushed to the first stroke with the battery attached, the switch (St) is turned on and the microcomputer (1) executes the flow from AFS in FIG. 2.

The microcomputer (1) first resets all flags and turns on the power supply transistor (Try). As a result, power is supplied to each circuit, and at the same time, the photometry circuit (3) starts photometry. The microcomputer (1) is a switch (91)
It is determined whether or not is ON, and if it is OFF, the process proceeds to step #15 and the above-mentioned process is performed, and if it is ON, the next focus detection and the subsequent flow are executed (S55).

When the switch (St) is ON, it is determined whether or not the auxiliary light flag (auxiliary light F) is set, and when it is set, the auxiliary light emitting device (13) is caused to emit light, assuming that the auxiliary light mode is active. Proceed to step #70, and if the auxiliary light flag is not set, skip step #65 and proceed to step #70 (#60.#65)
.

Next, the microcomputer (1) uses a timer (TI) to read the time (TI) taken from the start of the previous integration to the start of the current integration, and then
Reset and start, and start the integration (#7
0 to #78). In order to detect the relative position of the lens at this time, the value (CTI) of a counter (hereinafter referred to as event counter) indicating the amount by which the lens should be driven until it is in focus is read (S80).

Next is a flag indicating whether or not the mode has a long integration time (
Determine the long end F), and if that flag is set, 8
Wait for 0ssec to elapse, and if the integration is not completed even after 80a+sec has elapsed, turn on the auxiliary light emitting device (13).
0FFt, and proceed to step #110 (#85 to #
95). If the flag (long end F) is not set, the process proceeds to step #110 after 20+5 seconds have passed even when the integration is completed or not completed (#100.#105).

This integration is completed when the amount of light incident on the light-receiving element of the integration time control monitor provided near C0D (9) exceeds a predetermined value, but this is not directly related to the present invention and will therefore be explained below. is omitted.

In step #110, the value of the event counter is read as (Cr2) in order to know the relative position of the lens at the end of the integration. Furthermore, the microcomputer (1) dumps the CCD data and uses this data to perform focus detection calculations (#120, #125). Next, the value (M I ) indicating the relative position of the lens at the center of the previous integration is MIL,
To find the relative position of the lens at the center of this integration, divide the sum of the lens relative position at the start of integration (CTI) and the lens relative position at the end of integration (Cr2) by 2, and set this value as Ml. (# l :30.# I 35
). Next, we try to find the amount by which the lens was driven between the previous integration center and the current integration center, but we simply use MIL-M
It cannot be found by l.

The reason for this will be explained with reference to the graph in FIG.

In this graph, the horizontal axis indicates time, and the vertical axis indicates the amount of movement of the subject image on the film plane (a) and the lens movement (b).

In this figure, integration and calculations are performed while driving the lens. T, ,T,°, T1″° is the point at which the integration starts,
Tt, Tt', Tt'' are the points at the end of the integration, T3.T
3'.

T3°° indicates the end of the calculation, and now Tlo−T
3°', T, = Tffi'. The reason for this is that the time required for focus detection is
This is because most of the time is spent on focus detection calculations (#60 to #125). As the MIL indicating the lens relative position of the center of the previous integral I°, enter the value obtained by adding the event counter values indicating the lens positions at the integration start time TI' and the integration end time T2' and dividing by 2. . As a result of the calculation C'', the amount of defocus from the subject position REI converted into the number of encoder movements is input to the event counter at the end time T1'' of the calculation C''.This subject position REI is This is the position indicating the defocus (■) from the image plane at the center point of the integral Bi.

Next, Ml, which indicates the relative position of the lens at the center point of the current integral ■, is given by the object position R.
Input the value obtained by converting the defocus ■ from E2 into the number of encoder movements. Therefore, M indicating the relative position of the lens
I L and M I contain values of different scales, one having the previous result as the origin and the other having the current result as the origin. Simply convert this to MIL-Ml
However, the exact amount of lens movement cannot be calculated. Unless these scales are aligned, accurate lens movement cannot be obtained.

Therefore, let this correction amount be DT. This value DT is the subject position RE indicating the lens position at the end point T3' of calculation C.
It is obtained by taking the difference between the value of the event counter from I (CTa) and the value (L E RR) obtained by converting the value DF2° of the calculation result at this time into the number of encoder movements. That is, it is obtained by DT=LERR-CTa.

The amount of lens movement (ITI) can be found by subtracting the above-mentioned DT from the relative position Mr of the lens at the current center of integration from MrL. That is, rTI=M
Obtained by IL-(MI-DT). In the microcomputer (1), step #140 in FIG. #I45 does this.

Next, the microcomputer (1) inputs data from the lens circuit (12) including the open aperture value Avo and a coefficient value (hereinafter referred to as KL value) for converting the defocus amount into the number of pulses of the encoder/coder. , reads data from the ROM of the lens circuit (12). First 1. Set the chip select terminal (CS) to “H”
output a signal indicating the start of data communication, and set the variable N indicating the number of read data to 0,
Execute serial communication command (#155.#160). With this command, a clock is output from the terminal (SCK) of the microcomputer (1), and in synchronization with the rising edge of this clock! Data is output bit by bit from the lens circuit (12). Then, in synchronization with the fall of this clock, the microcomputer (1) reads data from the terminal (S I N) and outputs 8 pulses, completing one serial communication. and input the above two types of data from the lens circuit (12) (#165, #1
70). After inputting the two types of data, the terminal (C8
) to the "Low" level to notify the lens circuit (12) of the end of serial communication (#l75). Next, the process proceeds to an exposure calculation subroutine (#180).

This subroutine will be explained with reference to FIG.

The microcomputer (+) first inputs the open photometry value Bvo from the photometry circuit (3) and inputs the film sensitivity data Sv from the film sensitivity automatic reading circuit (4) (#2000).
, #2005). The exposure value Ev is calculated from these data and the open aperture value Avo input as described above (#2010). Next, determine the exposure control mode and
In mode, the exposure value Ev is halved to obtain the aperture value Av, and the shutter speed value TV is obtained by subtracting the aperture value Av from the exposure value Ev, and the process returns (#2015~
#2025).

In A mode, read the set aperture value Av,
Subtract the set aperture value Av from the exposure value Ev to find the shutter speed value Tv and return (#2030 to #2040)
. In S mode, read the set shutter speed value Tv, subtract the set shutter speed value Tv from the exposure value Ev to find the aperture value Av, and return (#2045 to #2C1
55). If it is not in any of the above modes, that is, if it is in M mode, read the set aperture value Av and glossy speed value Tv and return (#2.060~
#2065).

Returning to the flowchart of FIG. 2, if it is determined in step #185 that focus detection is not impossible, the process proceeds to step #I88 and the flag MVP is reset.

By resetting the flag MVP, shirt release is allowed even if there is large defocus or focus detection failure during quick shooting. If it is determined in step #185 that focus cannot be detected, the process advances to step #186. Step #1
At step 86, it is determined whether or not the continuous shooting flag is set, indicating that continuous shooting is in progress. If this continuous shooting flag is not set, the flow advances to LOWCON in order to perform a low contrast scan for detecting the contrast of the object while driving the lens. On the other hand, when the continuous shooting flag is set and does not indicate that a quick shooting is in progress, a flag (MV P ) indicating permission to perform the above-mentioned low contrast scan and prohibition of follow-up mode correction during release is set, and the CDr
Proceed to the NT flow and perform focus detection. The reason for this is that in this embodiment, shirt release is performed only when the subject is in continuous shooting mode and in AP priority mode, or when the object is in focus during release, and the subject is not in focus. There is. If a moving object is being photographed, or if the camera is accidentally moved slightly during continuous shooting, the desired object may fall out of the focus detection range against the photographer's intention. Normally, during continuous shooting, the amount of defocus should be relatively small or zero because the shooting interval is short, but in such a case, the camera's focus check mark may indicate that other subjects within the focus detection range are As a result of focus detection, focus detection may become impossible or a large amount of defocus may occur. It is not a good method to drive the lens by When the in-focus point cannot be detected, the lens is driven in accordance with the data of the previous focus detection result because the defocus amount data is not updated. If detection is possible, reset the low contrast flag LCF indicating that focus cannot be detected, and determine whether the subject is low light (the subject has low brightness below a predetermined value) (#1 B 5 to # 1 9 5 ).

If the light is not low light, the auxiliary light flag is reset in step #200, and if the light is low light, step #200 is skipped and the process proceeds to step #205, where the relative position of the lens at the end of this calculation is set as an event. Read with a counter. Next, the defocus amount Δε obtained by this calculation is multiplied by the conversion coefficient KL value to obtain the number of encoder pulses, and if this value is positive, the variable T indicating the current direction
Set D to 1, and if negative, set TD to 0 (# 2 0 5
~#225).

Next, an accuracy check subroutine is entered. The focus adjustment device used in this example includes:
It has an accuracy priority mode in which focus accuracy is prioritized over the time it takes to reach the in-focus state, and a speed priority mode in which priority is given to speeding up the speed at which the in-focus state is reached over accuracy. The speed of the lens control motor in this regard will be discussed later. In this subroutine, the above two modes are switched depending on the type of lens or various conditions at the time of photographing. Various aspects can be considered for this.

For example, as shown in Figure 5(a), when in continuous mode, the focus is often adjusted on a moving subject, so speed priority mode is used, and when in one-shot mode, the focus is on a stationary subject. Since there are many adjustments to be made, use precision priority mode. Alternatively, Fig. 5 (b
), when in A mode, you often want to accurately focus on a stationary subject such as a portrait, so use accuracy priority mode, and when using other exposure control modes, use speed priority mode. do.

Alternatively, as shown in Fig. 5(c), when the controlled aperture value (F number) is smaller than 1.7, it is considered that it is often used for portraits, etc., so the accuracy priority mode is set. In other cases, the speed priority mode is used, taking into account that the depth of field of the lens is somewhat deep. This limit F value may be arbitrarily selected from F4 to F5.6. Furthermore, as shown in Fig. 5(d), when the KL value for converting the defocus amount into the number of encoder pulses is large, that is, in a lens where the amount of change in defocus amount per number of pulses is small, it takes time to adjust the focus. If the KL value is small, the speed priority mode is selected, and vice versa, since accurate focus adjustment cannot be performed if the lens drive speed is too fast, and the accuracy priority mode is selected. In the latter case, even if the precision priority mode is set, the focusing state can be achieved with a small number of pulses, so the time required for focusing is relatively short.

In this embodiment, the flow is as shown in FIG. 5(e) so as to include all the judgments in the above four cases, and the judgment status is shown in Table 1. Here, regarding the case classification between accuracy priority mode and speed priority mode, the mode with more priority is set as the mode at that time. When there are the same number of priority modes, priority is given to the aperture value threshold. This is because a lens with a small F number has a very shallow depth of field, so even a slight shift is likely to result in an out-of-focus photograph.

Returning to FIG. 2, when the accuracy check mode is finished, it is detected whether the lens is stopped (#235). This can be determined by detecting the drive signal to the motor. If the lens has stopped, proceed to the MFZ routine; if not, proceed to the ID OB UN routine.

First, the routine of MP'Z will be explained with reference to FIG. The defocus amount Δε is stored in another variable Δε1, and the in-focus zone amount ΔIF (40 μ) is multiplied by the KL value to obtain the in-focus zone pulse number IFP. Next, a value CTC representing the amount of movement of the lens from the center of integration until the end of the calculation in terms of the number of encoder pulses is set to 0 (#240 to #250). Next, it is determined whether ERR, which indicates the defocus amount Δε by the number of encoder pulses (hereinafter referred to as the number of defocus pulses), is 3 pulses or less, and if it is 3 pulses or less, the current defocus pulse The number ERFL is the previous defocus pulse number LERR, and the current defocus direction TD is
is the previous direction LD, and the focus flag (focus F
) to display focus (#255 to #275)
. Then, a flag (AFEF) indicating the end of focus detection is set, and it is determined from the state of the switch (S4) whether or not it is continuous mode. If it is continuous mode, step #55 in FIG. CDIN from
Proceeding to the routine T, focus detection is performed again, and if it is one-shot mode, the microcomputer (1) waits for an interrupt and does not perform focus detection.

In step #255, the number of defocus pulses ER
If [ exceeds 3, it is determined whether the focus flag (focus F) is set, and if it is set, it is determined whether the number of defocus pulses ERR is within the predetermined number of focus zone pulses. If it is within the in-focus zone, proceed to the INFZ routine from step #260 (#2
90. #295). When the focus flag (focus F) is not set in step #290, if the current defocus direction TD and the previous defocus direction LD are reversed, or even if they are not reversed, the near zone described in detail later In the A judgment subroutine, within the near zone (NZ
F=1), reset the flag (ISTF) indicating that it has passed once, and step #29
Proceed to step 5 (#370 to #380).

The near zone A determination subroutine will be explained with reference to FIG.

The microcomputer (1) first sets the number of defocus pulses ERR to ERRl and determines whether the lens is stopped (#3
000. #3005). If stopped, step #30
If the lens is not stopped, the lens movement ff1cTC from the center of integration to the end of calculation is subtracted from ERRI, and the process proceeds to step #3015. In step #3015, it is determined whether or not a tracking flag (following F) indicating the tracking mode is set, and if it is set, a counter NZC indicating the near zone range is set to 63. If it is in non-tracking mode (when the tracking flag is reset),
In speed priority mode, set the near zone counter to 1.
If the accuracy priority mode is set, the near zone counter is set to 120, and the process proceeds to step #3035 (#3015 to #3030). Step #3035
Then, it is determined whether the defocus pulse number ERR1 is less than or equal to the set count value NZC of the near zone counter, and the count value of the near zone counter is NZC.
If it is below, a flag NZF indicating the near zone is set, and if the count value of the near zone counter exceeds NZC, the near zone flag NZF is reset and the process returns (#3035 to #3045).

Note that in this embodiment, the range of the near zone is changed depending on whether the mode is speed priority mode or accuracy priority mode.
In this case, it may be a constant value, for example 100, since it is not related to motor speed control.

Returning to FIG. 6, if it is determined in step #380 that the near zone flag (NF'Z) is set, the defocus amount increases for the moving subject from this step onwards. In this case, we will show a flow for correcting this, and we will refer to such a case as a follow-up mode. In step #385, it is determined whether a flag (lSTF) indicating that the passage has been passed once is set.

If this flag (ISTF) is not set, this flag (I5TF) is set, then the flag indicating the tracking mode (Following F) is reset, and the tracking correction flag (Following F) indicating that further correction is to be performed is set. Reset the correction F) and proceed to step #300 (#;455.#4
60. #445). If the flag (fsTF) indicating that it has passed once is set in step #385, determine the previous defocus direction (LD) and the current defocus direction (TD), and if the directions are different, That is, if both direction data are 1.0 or 0.1, step #4
Proceeding to 60, tracking correction in the tracking correction mode is not performed. If the previous defocus direction (LD) and the current direction (TD) are the same direction, that is, the data for both are 0.0 or 1.
．． If it is 1, proceed to step #400 and set the follow flag (follow F
) is set (#390 to #
400. #450). If the tracking flag is not set in step #400, WR is obtained by subtracting the previous number of defocus pulses LEER from the current number of defocus pulses ERR (#430). This value WR is predetermined!
If it is larger than iAA, that is, if the defocus amount (number of pulses) is large, a tracking flag (tracking F) is set, but in this embodiment, correction is performed when WR becomes a positive value twice. Therefore, I reset the tracking correction flag (tracking correction flag) that indicates the correction in tracking mode so that it will not be corrected the first time (#4
35. #440. #445).

This predetermined ff1AA is a value determined in consideration of noise components, and may be set to O if the configuration is free of noise components. If the above WR is less than AA, the defocus amount has not become large, so no correction is made and step #
Proceed to 460. In step #400, the following flag (
If tracking F) is set, step #430
Calculate WR in the same manner as above and determine whether it is greater than AA. If it is less than AA, the lens is keeping up with the movement of the subject and there is no need to make corrections, so the amount of correction is Step #300 with WR set to 0
Proceed to (#405.#410.#425).

On the other hand, if it is determined in step #41O that WR is greater than AA, the process proceeds to step #4!5, and step #415
Then, it is determined whether the difference WR between the previous and current calculation results is greater than or equal to the setting riAX, which is set larger than the count value NZC of the near zone counter. This setting value A
To explain why X is provided, during the tracking mode, that is, when the subject is moving, the subject may move out of the area provided for focus detection due to the movement of the subject. This is to prevent if the subject moves out of this area, another object within the area will be in focus. For this reason, if the correction ff1WR is greater than or equal to the set value AX, this means that the desired subject has moved out of the area, so the amount of movement of the lens is not updated. That is, if the correction ff1WR is equal to or greater than the set value AX in step #415, a non-update flag (non-update F) that prohibits updating of the lens movement amount is set, and the tracking correction flag is reset (#425). .#445). On the other hand, correction ff1W
If R is less than AX, reset the non-update flag and set the follow-up correction flag (#417 to #419) l,
Then proceed to step #300.

In step #295, if the defocus amount Δε1 is not within the focus zone, the process proceeds to step #300, and a focus flag (focus F) indicating the focus state is reset. Next, the current number of defocus pulses Ell is set to the previous number of defocus pulses L E RR, and the current defocus direction (TD) is set to the previous direction (LD) (#300.
#305). Then, it is determined whether or not the tracking correction flag (tracking correction F) is set, and if it is set, the tracking correction ff1 is added to the defocus pulse number ERR.
2WR is added to obtain a new defocus amount, and the process proceeds to step #322 (#315. #320).

In step #322, it is determined whether a continuous shooting flag indicating that rapid shooting is in progress is set.

If the flag is not set, step #355
Proceed to. On the other hand, if the snapshot flag is set,
Proceed to step #324 and defocus pulse number (ERr
() Determine whether or not the value is 000 or more, and if it is 1000 or more, it is assumed that the subject has gone out of the focus detection range during continuous shooting, and the lens drive is not controlled and the flag MVP is set.
and proceed to the CD INT flow. If the number of defocus pulses is less than several thousand months, the process advances to step #335 and the lens is driven. At this time, the corner drive counter EN
Since the contents of the ZCNT do not change, the lens is driven based on the previous focus detection result.

In step #335, if the tracking flag (following F) is set, the process proceeds to the subroutine of calculation (2) shown in FIG. In the subroutine of calculation (■), first, it is determined whether the mode is AF priority mode, and if it is AP priority mode, Td is set.
= 150 (msec), if in release priority mode, set Td = 100 (msec) and step #22
Proceed to step 15. This Td is, when release is possible,
It is provided to drive the lens by this amount when the release button is pressed down to the second stroke and the lens drive amount is not 0 (in focus state), Td = release time lag (,50m5ec) 10T C (certain time). Release time lag (≠ a value determined by the camera. On the other hand, TC is 100 m5ec in AP priority mode and 50 m5ec in release priority mode.

This value TC is generally changed in each mode by A.
P priority mode is a mode used when you want to accurately focus on the subject, so you want to move the lens as much as possible so that the amount of defocus becomes 0, so you drive the lens by increasing this fixed time. This is because I am doing so.

On the other hand, in release priority mode, it is important to release the camera at the exact moment you want to take the picture, so this fixed time is shortened. In the next step #2215, the integration period TI is read, Td is divided by this time TI to find the ratio R, and R is added to the correction amount WR in order to find the movement amount WS on the image plane of the subject moving during Td. Multiply (#2
215. #2220). Then, the number of defocus pulses ERR is added to this value WS to obtain a new number of defocus pulses ERRT (#2225). Next, it is determined whether the AF priority mode is selected, and whether the defocus pulse number ERRT is 148 or less in the AFff destination mode, and IOθ or less in the release priority mode, and if the defocus pulse number FRRT is less than or equal to these set values. If so, a tracking focus flag (tracking focus F) indicating that a focused state has been reached in the tracking mode is set, and if the set value is exceeded, the tracking focus flag is reset and the process returns. The above setting values will be explained later in the release mode.

Then, returning to step #340 in FIG. 6, it is determined whether the tracking focus flag is set as described above to see if it is within the tracking focusing zone, and if it is within this zone, the flag AFEF indicating the end of focus detection is set. , display the focus, and set the TIN.
Proceed to the NZ flow (#335 to #350). If the tracking flag (tracking F) is not set in step #335, or if it is set but not within the tracking focus zone in step #340, the process proceeds to step #355, and the defocus pulse number ERRT It is determined whether it is within the focus zone (#355). If it is within the narrow focus zone, a narrow focus flag is set and the process proceeds to step #365; if it is not within the narrow focus zone, step #360 is skipped and the process proceeds to step #365. In step #365, it is determined whether the defocus pulse number ERRT is within the display focus zone (described later), and if it is within the display focus zone, a flag AFEF indicating the end of focus detection is set and focus is displayed. , unless it is within the display focus zone, no display is performed and the process proceeds to TINNZ. Here, the focus zone will be explained.

(1) Focus zone (#295) This is a conventional area where the amount of lens drive required to reach the in-focus state once becomes 0, and if the integration result with the lens stopped is in this area. Displays that the camera is in focus.

(2) Display focusing zone (#365) This is wider than the focusing zone in (1), and is the range in which the lens can be moved accurately into the above focusing zone during the release time lag after the release. , number of pulses 2
Defocus amount equivalent to 1 (varies depending on the lens)
It is said that Regardless of whether the lens is stopped or moving, if the defocus amount falls within this range, a display is performed and release is permitted in the AP priority mode.

(3) Follow-up focusing zone (step #340) This is the widest zone and indicates the range in which focus is displayed in the follow-up mode and release is permitted in the AF priority mode. When the lens continues to follow the movement of the subject while driving the lens in the tracking mode, the camera may not be in focus (defocus amount is 0). However, in the conventional AF priority mode, the release cannot be performed unless the lens stops. This tracking focusing zone is provided to prevent this, and the size of this zone is set to a value that allows the lens to be driven within a certain period of time equal to the release time lag.

This value will be explained in detail when the release flow is explained later.

(4) Narrow focus zone (#355) This zone is almost the same as the focus zone (1). The reason for this zone is as follows. When the lens is driven within this zone, the amount of movement CTC of the lens from the center of integration to the end of calculation is subtracted from the number of differential pulses. The number of defocus pulses is now the value at the center of integration, but it may not necessarily be the value at the center of integration due to changes in light, hand shaking, or electrical noise. Therefore, even if you subtract the amount of lens movement from this number of defocus pulses, the correct amount of defocus may not be obtained, and even if the lens is driven by this amount of defocus and then stopped, it may not be in focus. . In such a case, the lens will have to be moved again based on the result of the next focus detection, and if a similar situation occurs during this drive, the lens will have to be driven based on the result of the next focus detection. This zone is provided to prevent the lens from stopping due to detection of the in-focus state no matter how long it takes. Therefore, when the amount of defocus falls within this narrow focusing zone, focus detection is not performed and the lens is driven until the number of defocus pulses becomes zero.

On the other hand, in FIG. 2, if the lens is not stopped at step #235, the flow advances to ID0BUN shown in FIG. 8.

In the flow of ID0BUN in FIG. 8, first, it is determined whether the defocus direction calculated this time is different from the defocus direction calculated last time (#435). If the direction is reversed, stop the lens (step #455),
CD from step #55 in Figure 2 to perform the integration again.
Return to INT flow. On the other hand, step #4 in Figure 8
If the direction is not reversed in step 35, find the movement ff1cTc of the lens from the center of integration to the end of the calculation (#
435, #440). Next, the process proceeds to a subroutine for near zone A determination, which will be described later. If the near zone flag (NZF) is set as a result of the determination within that subroutine, the process proceeds to step #460; if it is not set, follow-up is performed in step #520. Reset the flag (#4
45. #450). In step #460 and subsequent steps, it is determined whether the defocus direction (LD) calculated last time and the defocus direction (TD) calculated this time are the same direction, and if they are the same direction, the process advances to step #470 and the defocus direction (TD) calculated this time is Add the driving fllTI of the lens that moved between the previous integration center and the current integration center to the pulse number ERR, and subtract the previous defocus fiLERR to find the correction amount wn (#460 to #470. #515).

Next, it is determined whether or not the following flag (following F) is set, and if the following flag is not set and furthermore, this correction amount WR is greater than or equal to the predetermined flAA, the following flag (following F) is determined.
Set the tracking correction flag (tracking correction F) and tracking correction flag (tracking correction F), respectively, and proceed to step #300 in FIG. 6 (#480
~#490).

On the other hand, in step #480, the correction ff1WR is adjusted by a predetermined amount Δ
If it is less than A, reset the tracking correction flag (tracking correction F) and proceed to step #300 (#480, #485
). When the tracking flag (tracking F) is set in step #475, it is determined whether the correction amount WR is greater than the predetermined amount AX (the count value NZC of the azone counter is large), and if it is greater than the predetermined amount, the focus It is determined that the subject has moved away from the detection area, a non-update flag (non-update F) that prohibits updating of the lens drive amount is set, a tracking correction flag (tracking correction F) is reset, and the process proceeds to step #300 ( #500. #505. #490).

Conversely, if the correction amount WR is less than the predetermined amount AX in step #500, the non-update flag (non-update F) is reset, the follow-up correction flag (follow-up correction F) is set, and step #3
Proceed to 00 (#500.#510° #490).

Returning to FIG. 2, when it is determined in step #185 that focus detection is impossible, the process proceeds to the LOWCON flow in FIG. 9. In the LOWCON flow shown in Figure 9, the microcomputer (1) first determines whether or not the following flag (following F) is set, and if the following flag (following F) is set, the non-update flag is flagged. (Non-update F) is set (#520° #525). And passing through here! It is determined whether or not the flag PIF indicating that it is the third time has been set, and if it is not set, that is, it is the third time that the passage has passed, this flag PIF is set, and the variable N1 is set to 0 as shown in Fig. 2. Proceed to the CDINT flow following step #55 (#530, #625.#
630).

In step #530, if the flag PIF is set, 1 is added to the variable Nl, and this value N
Determine whether 1 is 2 or not, and if it is not 2, the second
Proceed to the flow of CD INT following step #55 in the figure, and if it is 2, reset the following flag (following F) and non-update flag (non-updating F), and then proceed to step #55.
Proceed to step 555 (#535 to #550). Steps #520 to #550 described above. #625. With #630, if the subject moves out of the focus detection area while in tracking mode, the amount of defocus may suddenly increase or it may be determined that focus cannot be detected, so we have taken measures to prevent this. be. In other words, when the focus can be detected even if the defocus amount suddenly increases, it means that the correction ff1WR suddenly increases, and in this case, the process is performed in steps #500 to #51O in FIG. ing. On the other hand, if it is determined in step #185 of FIG. 2 that focus detection is impossible, the process proceeds to the LOWCON flow of FIG. 9.

When it is determined that focus cannot be detected in tracking mode, that is, when the subject moves out of the focus detection area,
The lens is driven based on the previously calculated defocus amount without performing the normal focus detection failure processing from step #555. On the other hand, if the follow flag is not set in step #520, the flag PIF
is reset, and the process proceeds to step #555.

After step #555, count interrupts, timer interrupts, and ENT'EVENT interrupts, which will be described later, are prohibited (#555 to #557). Next, whether or not the cause of the determination that focus cannot be detected is that the brightness of the subject is too low (low light) is detected by the output of the light receiving element provided near the photodiode of the COD. If the cause of focus detection failure is this low light, it is detected whether or not the auxiliary light emitting device (13) is installed in the camera, and if the auxiliary light emitting device (13) is installed, the auxiliary light emitting device (13) The light emission mode is set, and it is determined whether the auxiliary light flag (auxiliary light F) is set (#560 to #570). When the auxiliary light flag (auxiliary light F) is set in step #570, that is, when the auxiliary light is emitted once but the focus cannot be detected due to low light,
The microcomputer (1) waits for an interrupt to display a low contrast display indicating that focus detection is not possible and to stop focus detection (#5
70, #585, #590). Conversely, if the auxiliary light flag is not set in step #570, this flag (auxiliary light F) is set, and a long end flag (long end F) indicating a mode with a long integration time is set. The process proceeds to the flow CD I NT following step #55 in FIG. If it is determined in step #555 that the light is not low light, or if it is determined in step #565 that the auxiliary light emitting device (13) is not loaded, a low contrast display is performed (#595). Then, a flag LBF indicating the lens retraction mode is determined, and when this flag LBF is not set, a command is issued to control lens extension, whereas when the flag LBF is set, a command is issued to control lens retraction, and seven lenses are driven. After outputting a command to drive the motor, the process proceeds to the focus detection flow CDINT following step #55 in FIG. 2 and performs focus detection (#60
0. #605. #610. #615).

Next, the flow of lens drive control shown in FIGS. 10 to 13 will be explained. First, before that, speed control of the lens drive motor in the embodiment will be explained. There are five types of motor speed: speed outside the near zone (out zone), three speeds within the near zone, and step drive. In each mode, the above five types of lens speed control are performed depending on the number of defocus pulses at that time. To explain these things as shown in Table 2, the rotational speed of the motor is 20.00
Orpm (out zone), near zone 1) at 5.00 Orpm, near zone 2) at 2.50 Orpm, 1.0
There are five types of drive: near zone 3) at 0 rpm, and step drive. Of these, the step drive is used only in the non-following mode, which prioritizes accuracy, to perform lens control with high precision. The difference in lens speed with respect to the number of defocus pulses in the near zone is such that the faster the speed required to reach focus, the faster the lens speed. The faster the motor speed is shifted, the less accurate the stopping accuracy tends to be. How these speed controls are performed in the camera sequence will be explained below.

First, the flow of TINNZ shown in FIG. 10 will be explained. In step #630, the microcomputer determines whether or not the lens is stopped, and determines whether a flag (non-update F) indicating that the lens drive amount is not updated when the lens is not stopped is set. If it is set, do not update the lens drive amount and proceed to step #7.
Proceed to 00 (#630, #635). Step #63
When the lens is stopped at 0, step #680
The process advances to a near zone determination subroutine that determines whether or not the vehicle is in the near zone. This near zone subroutine is number one! It is shown and explained in the figure.

At step #2300 in FIG.
) determines whether or not the following flag (following F) is set, and if it is set, sets the count value NZC of the counter indicating the near zone range to 63, and conversely sets the non-following mode (following flag reset ), if the speed priority mode is selected, the count value NZC of the near zone counter is set to 100. In the accuracy priority mode, set the count value NZC of the near zone counter to 120 and proceed to step #2310 (#2300,
#2305. #2325-#2335). Step #2
In step 310, it is determined whether the defocus pulse IER[ is less than or equal to the set count value NZC of the near zone counter, and the count value NZ of the near zone counter is determined.
If it is less than C, a flag NZF indicating the near zone is set, and if it is equal to or greater than the count value NZC of the near zone counter, the near zone flag NZF is reset and the process returns (#2310 to #2320).

Then, the process returns to step #685 in FIG. 1O, and it is determined whether or not the near zone flag NZF is set.
When not set, the number of defocus pulses E
The value obtained by subtracting the count value NZC of the near zone counter from RR is input to the event counter EVENTCNT (#685 to #690). Kono event counter E
V E N T CNT is the encoder (11
) is subtracted by 1 each time a pulse is sent from the counter, and when the contents of the counter reach 0, an interrupt (INTEVENT) indicating entry into the near zone is executed.

After completing the manual input to the event counter EVENTCNT, the event counter set (EV
The process proceeds to a subroutine (ENTCNT set), and upon completion of this subroutine, the process proceeds to step #700. This subroutine is shown in the upper right corner of FIG. 10 and will be explained.

In this subroutine (EVENTCNT set), the interrupt (INTEVENT) by this event counter is
), disables timer interrupts and counter interrupts (CNTR interrupts) to be described later, and returns (#2350
~#2360).

At step #635 in FIG. 10, the non-update flag (
When non-update F) is not set, subtract the amount of movement CTC of the lens from the center of integration to the end of calculation from the number of defocus pulses ERR to determine the number of defocus pulses to be actually driven. Proceed to the near zone determination subroutine described above (#645, #650
). In this subroutine, the flag NZF indicating the near zone
is not ceratified, the count value NZC of the near zone counter is subtracted from the number of defocus pulses ERR and the count value of the event counter EVENTCNT is set as the count value of the event counter EVENTCNT.
Set), and through this subroutine, proceed to step #700 (#655.#670.#6
75). When the near zone flag NZF is set in step #655 or step #685, the number of defocus pulses ERR is input to the drive counter ENZCNT, and the process proceeds to the timer set subroutine shown in FIG. After completion, the process advances to step #700 (#660, #665). In this subroutine, each mode shown in Table 2 (following mode,
Regarding speed priority and accuracy priority in non-tracking mode), the motor speed is determined for the number of defocus pulses in the near zone. The speed control of the motor in this embodiment involves turning on the power to the motor depending on whether or not a pulse is sent from the encoder within a predetermined time.
The speed of the motor is changed by turning off and keeping the speed of the motor constant, and changing the predetermined time. The shorter this predetermined time is, the faster the motor speed is, and the timer equivalent to 5,000 revolutions per minute is AI, 250
The timer corresponding to 0 rotations is A2, and the timer corresponding to 1000 rotations is A3, and the relationship is AI<A2<A3.

The details of the timer I set subroutine shown in step #665 in FIG. 1O will be explained with reference to FIG. The timer is set, and in steps #2460 and #2465, count interrupt and timer interrupt are respectively permitted and the process returns. Here, a,= 61, a3= 30,
b, = 31, bt-15+c1=79, ct=
It is 31. If flag 5TEPF indicating step drive mode is set in step #2435,
Proceed to step #2470. In step #2470,
Determines whether the motor is running or stopped, and if not stopped, is the step drive flag 5TPDRF set, which indicates that a count interruption was performed by an encoder pulse at the value of the drive counter that should perform step drive? is determined, and if this flag 5TPDRF is set, this flag 5TPDRF is reset and DI is set in the timer (#2470 to #2
485). On the other hand, if the motor is stopped or the step drive flag 5TPDRF' is not set, this flag STPDRF is set and the timer is set to D2 (#2470.#2475.#
2490.2495). The driving time at this time is shorter.
DI<D2.

Referring to FIG. 10, the motor is driven in step #700. Then, it is determined whether the near zone flag NZF' is set, and if it is not set, a moving integration flag NIDF indicating that integration is to be performed while moving the lens is set (#705, #745). next,
Determine whether or not the motor is stopped. If the motor is stopped, wait a little while for the motor to rise, and then proceed to step #.
Proceed to 735, and if not stopped, immediately proceed to step #7
Proceed to step 35 (#750.#755). Step #735
Then, the microcomputer (1) determines whether the defocus pulse number ERR is within the narrow focus zone, and if it is within the narrow focus zone, the microcomputer (1) moves the lens by the remaining defocus amount without performing integration. Control waits for an interrupt, and if it is not a narrow focus zone, the process proceeds to the focus detection flow CDINT following step #55 in FIG. 2 (#735, #740). If the near zone flag NZF is set in step #705, the process advances to the flow of WNZ3 and first determines whether or not the moving integral flag (NIDF) is set, and if it is not set, the process advances to step #735. move on(#
710). On the other hand, in step #71O, the moving integral flag (
If NIDF) is set, the process proceeds to a near zone 3 determination subroutine in which it is determined whether the count value ENZCNT of the drive counter is within the number of defocus pulses of near zone 3 (see Table 2).

The details of this near zone 3 determination subroutine are shown in FIG. 15 and will be explained. First, it is determined whether or not the following flag (following F) is set, and when this flag (following F) is set, If the count value ENZCNT of the drive counter is 15 or less, set flag NZ3F indicating that it is within near zone 3 and return.
When NZCNT exceeds 15, flag NZ31? Reset and return (#2500 to #2510.
#2535). Conversely, when the speed priority mode is set in the non-following mode, the drive counter count value ENZC
If NT is 30 or less, flag NZ3F is set and 3
If it exceeds 0, reset and return. Furthermore, when the non-following mode is the precision priority mode, the flag NZ3F is set when the count value ENZCNT of the drive counter is 31 or less, and when it exceeds 3I, the flag NZ is set.
Reset 3F and return.

Returning to FIG. 10, if the near zone 3 flag NZ3F is not set in step #715, that is, if the near zone 3 area is not entered, step #712 is executed.
Go back, enter the near zone 3 area and flag NZ3F
When is set, the movement integral flag NIDF is reset (#720). Next, follow flag (follow F)
Determine whether or not is set, and if it is set, or if the following flag (following F) is not set but the speed priority mode is set, step #7
Proceed to step 35 (#725.#727). In precision priority mode, the lens stops (drive counter count value E
Step #727 until NZCNT becomes 0)
repeat. This is because the step drive in the accuracy priority mode does not have a constant speed, so movement integration cannot be performed correctly.

The above-mentioned moving integral will be explained with reference to FIG. 21.

In FIG. 21, the vertical axis represents the rotational speed of the motor, and the horizontal axis represents time. The upper part shows whether moving integration is possible depending on the state of the motor. In this example, 2
Until entering near zone 3 during deceleration from 0,00 Orpm, during step drive, and from motor stop to 20
, movement integration is prohibited during acceleration to 00 rpm. This is because acceleration and deceleration are not always constant during these periods, so the center of integration during movement is not clear, and it is thought that there are many errors in focus detection. On the other hand, when accelerating into or toward the near zone, the focus detection error is only a few encoder pulses because the motor speed is originally slow and the acceleration time is short. Even if we perform integration, it is of no practical use. Therefore, in this embodiment, the time required for focus adjustment is shortened by enabling movement integration as much as possible.

Next, returning to FIG. 1θ, the event counter interrupt INTEVENT shown in the lower right corner will be explained. The event counter (EVENCNT) subtracts 1 from the count value every time a pulse is received from the encoder (ll), and when the count value of this event counter reaches 0, the interrupt INTEVENT flow is entered. In this flow, first, in step #2550, the INTEVENT interrupt is prohibited, and flag RESF determines that the release is in progress.
If this flag REsF is set, the drive counter E
Input 40 to the count value of VENCNT, proceed to the timer R set subroutine described later, and control the rotational speed of the motor (#2550. #2555, #2570.
#2575). If the flag RESF is not set and the release is not in progress at step #2555, the count value of the near zone counter NZC is entered into the count value of the drive counter ENZCNT, and the process proceeds to the subroutine for setting the timer, which will be described later. , set the near zone flag NZF and proceed to the flow of WNZ3 with step gaff 10 or less (#2560 to #2567)
.

Next, the counter interrupt (CNTR interrupt) shown in Figure 12
Explain. This counter interrupt is executed every time a pulse is generated from the encoder (11) in FIG. When entering this flow, the microcomputer (1) first subtracts one from the count value of the drive counter ENZCNT, and determines whether the count value of the drive counter ENZCNT has become 0 (#800 to #805). and drive counter E
If the count value of VENCNT is not 0, it is determined whether the step mode flag 5TEPF indicating step drive is set (#815), and if it is set, the process advances to step #835.

If the flag 5TEPF is not set in step #815, the process advances to step #820, and if the accuracy priority mode is not set, or if the count value of the drive counter ENZCNT exceeds 6 even in the accuracy priority mode,
Assuming that step drive is not performed, the process proceeds to step #840. Here, it is determined whether or not a flag TIPASF indicating that a timer interrupt has occurred before the main counter interrupt is set, and if it is set, it is reset and the process returns. If this flag TIPASF is not set, the motor is de-energized (#
845). On the other hand, in step #820, the accuracy priority mode is selected and the count value of the drive counter ENZCNT is 6.
In the following cases, step #825 to step #83
0, sets the flag 5TEPF indicating the step mode, further sets the step drive flag 5TPDRF, and then turns off the motor in step #845 (
#830. #835. #845). Next, it is determined whether or not the flag RESF indicating that the release has been set is set, and if it is set, the process proceeds to the timer R set subroutine, and if it is not set, timer 1 is set.
The program proceeds to the set subroutine, and returns after the subroutine ends (#850 to #860). Regarding the timer R setting, it will be explained at the time of release.

In step #805, drive counter ENZCN
When the count value of T becomes 0, that is, when the lens has finished driving to the in-focus point, the motor is stopped, the step mode flag 5TEPF' is reset, and timer interrupts and count interrupts are prohibited (# 870~#88
0). Then, when the release flag RESF is set, the process returns, and when it is not set, the process proceeds to the DRVED flow described later (#885).

In this DRVED flow, first, it is determined whether or not the flag I5TDF is set, which indicates that the flow when the count value of the drive counter ENZCNT becomes 0 in the one-shot mode is set. If so, the process advances to the focus detection flow CDINT starting from the second step #55 (#895). If this flag I5TDF is not set in step #895, the process advances to step #900 and the switch (S
Determine whether it is continuous mode or one-shot mode from the state of 4), and if it is one-shot mode, set the focus flag, and further set the flag I5TDF indicating that this phase has been passed once. Proceed to focus detection flow CD INT (#900° #910. #915)
. If the continuous mode is selected in step #900, it is determined whether or not the tracking flag is set, and if it is set, the process returns and continues focus detection using the data at that time. Increase tracking ability and if not set, step #2 in Figure 6
Proceeding to the flow of INFZ below 60, control such as focus display is performed (#905).

FIG. 13 shows the flow of timer interrupt. This timer interrupt is executed when no pulse is sent from the encoder within the time set by the timer 1 set routine. In FIG. 13, the microcomputer (1) determines the flag RESF in step #950, determines whether or not this timer interrupt was performed during the release, and if the timer interrupt is not performed during the release, the microcomputer (1) executes the timer 1 set subroutine described later. If the release is in progress, the process proceeds to a subroutine for setting timer R, which will be described later (#950 to #960). Next, flag 5TEPF is determined to determine whether or not the mode is step mode, and if it is not step mode, the flag T I PASF indicating that a timer interrupt has been performed is set, the motor is energized, and the process returns ( #965~#975).

When in the step mode, it is determined whether the flag 5TPDRF indicating step drive is set, and if it is set, the motor is energized, and if it is not set, the motor is energized. Return (#975.#980.#985).

When the release button is pressed down to the second stroke and the release switch (S2) is turned on while the above-mentioned focus detection and focus adjustment are being performed, a signal changing from rHJ to rLJ is sent to the terminal (1) of the microcomputer (1). INT2) and the release interrupt flow shown in FIG. 16(a) is executed. First, the microcomputer (1) determines whether or not film winding has been completed, and if so, prohibits release interrupts and APS interrupts from step #45 in FIG. 2(a). and set the release flag RESF indicating the release mode (#l 000 to #1012
).

If film winding is not completed in step #1000, it is determined whether the release switch (S2) is turned on, and if it is turned on, step #1
000, wait for the winding to be completed, and when the switch (S2) is OFF, the CD from step #55 in Figure 2 and below.
Proceed to INT flow.

When the release flag RESF is set in step #10I2, the interrupt INTEVENT for entering the near zone from the out zone is prohibited in step #1014, and it is checked whether the near zone flag NZF is set in step #1016. judge. When the near zone flag is not set in step #l016, no value is set in the drive counter, so the count value of the drive counter is calculated by adding the count value of the near zone counter NZC to the count value of the event counter EVENTCNT. Step #1025 as value ENZCNT
Proceed to. In step #1025, the state of the switch (S6) is detected to determine whether or not the AF priority mode is set. If the mode is At' priority mode, the process proceeds to step #1110, and if the mode is release priority mode, the process proceeds to step #1030.

Next, in FIG. 16(a), in step #1025, A
When the F priority mode is selected, the process proceeds to step #1109, and it is determined whether a flag (MVF') indicating permission for release and prohibition of follow-up correction during release is set.

If it is set, it is determined in step #1110 whether a flag (REEF) indicating that the previous photographing was performed with an undetectable focus or with a large amount of defocus has been set.

If this flag (REIF) is not set, the flag (REIF) is set in step #1112 assuming that the previous release was in focus and the release operation (shooting) started, and the process proceeds to step #1190 to perform the current release. .

If the flag (REIF) is set, the process proceeds to step #1170 to prohibit release for the reason described above.

If the flag MvF indicating release permission is not set in step #1109, step #11
The process proceeds to step #1112, and it is determined whether or not the flag (AFEF) indicating the end of focus detection is set. If it is set, the process proceeds to step #1113, in which it is determined that focus detection is not possible or that the photographing is being performed at a large defocus. The flag that indicates (
REIF) and proceed to step #I 115. - Step # to prohibit release when the flag (AFEF) indicating completion of focus point detection is not set.
Proceed to 1170.

Starting with the release priority mode, first, it is determined whether it is the follow mode or not by whether the follow flag (follow F) is set, and if it is the follow mode, the process proceeds to the subroutine of calculation (2) in step #1035. This operation■
In the subroutine, the release time lag (switch (
The amount of movement of the subject is estimated during the time period from when S2) is turned on until the actual start of exposure is performed, and the value is set as the sum of this amount and the defocus amount until entering this mode (release). I'm looking for the amount of focus. This subroutine is shown in FIG. 17 and will be explained.

In the subroutine of calculation I in Fig. 17, the movement of the subject in one cycle of focus detection time, that is, the tilt of movement of the subject in the optical axis direction (converted to defocus amount) in a unit focus detection time, is calculated, and during the release time lag, the movement of the subject in the optical axis direction is calculated. Find the amount of movement (converted to defocus amount) of a moving subject. That is, in step #2600, the ratio R is obtained by dividing the release time lag time R9T by the unit focus detection time TI, and the movement amount WS during the release time lag is obtained by multiplying the ratio R by the subject movement fiWR in the unit time. This is added to the count value of the drive counter ENZCNT to obtain a new count value of the drive counter ENZCNT, and the process returns (#2600 to #2610).

Returning to FIG. 16(a), if the tracking mode is not determined in step #1030, the subroutine of calculation (2) is skipped and the process proceeds to step #1036. Then, it is determined whether the count value of the drive counter ENZCNT is 3 or less, and 3
If it is less than 3, it is determined that the focus is in focus, the motor is stopped, and the process proceeds to step #lI90; if it exceeds 3, the process proceeds to step #1140 (#1136.#1137). The flow from step #1140 described below is to drive the lens during the release time lag when release is permitted. In step #1O40,
It is determined whether the count value of the drive counter ENZCNT is 13 or less, and if it is 13 or less, a flag eIF is set to set the motor speed to lOOOrpm, and the process proceeds to the subroutine for setting timer R (#108).
0. #l090).

When the count value of the drive counter ENZCNT is greater than 13 and less than 40, the process proceeds to the timer R setting subroutine (#1045.#1090). Furthermore, drive counter E
If the count value of NZCNT is greater than 40 and less than 66, flag e2F' is set to set the motor speed to 500 Orpm, and the process proceeds to the subroutine for setting timer R (#1050° #l085. #l090).

The timer R set subroutine shown in FIG. 19 will now be explained. This is a routine that sets a timer for setting the motor speed, similar to the timer 1 set subroutine. First, in step #2780, it is determined whether or not the AP priority mode is set, and in the case of the AF priority mode, the process proceeds to step #2785. This will be discussed later. On the other hand, when the release priority mode is selected, the flag e
Determine whether or not IF is set, and if it is set, proceed to step #2760 and set timer I to A.
3 (equivalent to 1000 rpm), enable timer interrupts and count interrupts, and return (#2765, 2
770). If the flag eIF for setting I000 rpm is not set in step #2705, the flag e2 for setting 500 rpm is set in step #2710.
Determine whether or not F is set, and if it is set, proceed to step #2800 and set the flag F to correct the torque α1 that goes too far when the motor is stopped.
Determine whether e2F is set and set this flag Fe.
If 2F is set, AI is set in timer 1 (equivalent to 5000 rpm) in step #2830, and the process proceeds to step #2765. If flag Fe2F is not set in step #2800, step #2
This flag Fe2F is set in 805, and step #2
At 810, this excess amount α1 is added to the count value of the drive counter ENZCNT'r to create a new count value of the drive counter ENZCNT, and step #28
Proceed to step 30 and set timer 1 to AI. To explain the amount of overshoot, if the motor is stopped from lOOOrpm, the amount of overshoot is small enough to be ignored, but if the motor is stopped from 5000 rpm, the amount of overshoot will be large. This amount is almost unique to the rotational speed of the motor, and the variation for each lens is small, so if you add a partial value αl to the count value of the drive counter ENZCNT, the lens will reach the in-focus position. The motor starts to stop in front of you, allowing you to stop the motor correctly when the lens reaches the in-focus position.

Step #2705. Flag eIF in #2710.

If e2F are not set together, step #
At step 2745, it is determined whether or not the count value of the drive counter ENZCNT exceeds 00. If it exceeds the count value of the drive counter ENZCNT, 40 is subtracted from the count value of the drive counter ENZCNT and entered into the count value EVENTCNT of the event counter. Set (EVENT
Proceed to the subroutine of CNT set) and return (
#2730, #2735).

If the count value of the drive counter ENZCNT is 100 or less in step #2745, the process proceeds to step #2750, where it is determined whether the count value of the drive counter ENZCNT is greater than 14. If it is greater than 14, the process proceeds to step #2830. Set timer 1 to AI (500
0 rpm) and proceed to step #2765. Furthermore, in step #2750, the drive counter ENZCN
If the count value of T is 14 or less, step #2755
The count value of the drive counter ENZCNT is 4.
Determine whether or not it exceeds. And drive counter E
If the count value of NZCNT is 14 or less but greater than 4, timer l is set to A2 (2500 rpm) in step #2850.
If it is 4 or less, set timer l to A3 (equivalent to +000 rpm) in step 82760.
Furthermore, in steps #2765 and #2770, timer interrupts and count interrupts are enabled, and the process returns.

Returning to FIG. 16(a), in step #1050, when the count value h of the drive counter ENZCNT exceeds 66, the count value of the drive counter ENZCNT cannot be set to 0 (in focus) below 5000 rpm, so The release time lag is increased by an amount of time (in this example, 50 m5ec when not in AF priority mode), and the motor is driven during this time.However, in continuous shooting mode, which indicates continuous shooting mode, it is necessary to shoot as quickly as possible. The lens is not driven until a predetermined time corresponding to the increase in time lag is provided.

Therefore, in step #1055, the state of the switch (S8) is detected to determine whether the mode is continuous shooting mode or not, and if it is the continuous shooting mode, the process advances to step #1095. on the other hand,
If it is not the quick shooting mode, the process proceeds from step #1055 to step #1060, where it is determined whether or not the tracking mode is in effect. If the tracking mode is in the tracking mode, the amount of movement of the subject is calculated within the predetermined time set in step #1065. Arithmetic ■
After executing the subroutine, the process proceeds to step #l070. On the other hand, if the tracking mode is not selected in step #1060, it is determined that the subject is stationary, and step #10
65, and proceeds to step #1070, where the timer is set in the above-mentioned timer R setting subroutine according to the count value of the drive counter ENZCNT, and the timer is set in step #1070.
Wait 0m5ec and move the lens during this time. (# l
060~#1075).

Next, the subroutine of operation (2) in step #1065 is shown in FIG. 18 and will be explained. In this subroutine, first, in step #2650, it is determined whether or not the AF' priority mode is set, and if it is the AP priority mode, the time TO is set to 100m5.
ec, if in release priority mode, set time TC to 50m5
ec, in step #2665 this time TC is divided by the unit focus detection time TI to find the ratio R, and in step #2
In step 670, the defocus amount (count WR) of the object moving within the unit focus detection time is multiplied by this ratio R to obtain the follow-up delay defocus amount WS until exposure, and step #2675
Then, WS is added to the count value of the drive counter ENZCNT to obtain a new count value of the drive counter ENZCNT, and the process returns. Step #1055. #1075
．． In step #1095, proceeding from #1090, it is determined whether the motor speed is low speed (5000 rpm or less), and it is determined whether the motor speed is not low speed (i.e. 20 rpm or less).
000 rpII+), the motor does not stop immediately even if the motor stop signal is output, so a motor brake signal is output (#1095.#l 1
00).

Then, in steps #1103 and #1107, count interrupts and timer interrupts are respectively prohibited, and step #1
Proceed to I90. If the speed is low in step #1095, the process directly advances to step #1190. Step #1
025, when the AP priority mode is selected, it is determined whether the flag AFEF indicating the end of focus detection is set, and if it is not set, the release flag RES is set.
Reset F and return (#1110.#11
70).

In this embodiment, even if the in-focus state is detected again after the end of exposure, the release button will not be released if it continues to be pressed, and will be released if it is pressed again, but here, in step #1170, the release flag is If RESF is not reset, and the release flag RESF is determined in the next step after step #250, and if it is set, the process proceeds to step #1115, it is possible to release the lens immediately after focusing.

If the flag AFEF is set in step #1110, it is determined in step #1115 whether or not it is in the tracking mode, and if it is not in the tracking mode, it is determined in step #1115.
Proceed to 90. When in follow mode, step #1
120 Calculation I subroutine (shown in Figure 17) calculates the distance of the subject moving during the release time lag, and if the count value of the drive counter ENZCNT is 13 or less, a flag is set to control the motor at 100 Orpm. After setting flF, the program proceeds to the timer R set subroutine to set a timer for motor speed control, and then proceeds to step #1I90 (#1120, #112
5. #1175. #I 185).

If the count value of the drive counter ENZCNT is 21 or less in steps #11 and 25, the process proceeds from the subroutine for setting timer R in step #1185 to step #119.
Go to 0. Further step #I! Drive counter E at 40
When the count value of NZCNT exceeds 21, it is determined in step #l 145 whether or not the mode is continuous shooting mode, and if it is continuous shooting mode, shooting is performed immediately as explained even in the case of release priority mode. If so, proceed to step #1190. If it is not the continuous shooting mode in step #I 145, the API (first mode) will take a predetermined time (100m5e) to bring the lens to the focusing position.
c) Perform control to move the lens. In other words, including the release time lag (50m5ec), it is 150m5ec.
The lens is brought to the in-focus position by applying the

Here, we are currently in follow mode, so this 100m5e
In order to find the amount of defocus that the subject moves during c,
In step #1150, the process proceeds to the calculation subroutine (2) to obtain the necessary count value of the drive counter ENZCNT. Then, in order to control the speed of the motor based on this value, the timer R set subroutine ζ is advanced for 100 m5.
Wait for ec (#1150 to #1165).

Here, the case where the timer R is set in the AP priority mode will be explained with reference to FIG. 19. In the case of AF priority mode, the process proceeds from step #2780 to step #2785, and when the flag rlF' indicating 11000 rp drive is set, the process proceeds to step #2760, where timer 1 is set to A3 (equivalent to 1000 rptt+). If the flag rlF is not set at step #2785, the drive counter E is set at step #2790.
Determine whether the count value of NZCNT is 28 or less,
If it is not less than 28, the time A corresponding to 5000 rpm
Set 1 to timer 1. Similarly, drive counter EN
If the count value of ZCNT is 8 or less, step #2
Proceed to step #2760 from 795 and set timer l to A3.
If the value is greater than 8 and less than or equal to 28, the process proceeds from step #2795 to step #2850, where the timer 1 is set to A2 and the motor is controlled to 250 Orpm.

Table 3 shows the relationship between the motor rotation speed and the encoder pulses and the time required for focusing for each of the AP priority mode and release priority mode.
It is. To briefly explain the relationship between the rotation speed of this motor and the pulses, in AF priority mode, the shutter speed is higher than in release priority mode because this mode is selected so that the shutter is released when the lens reaches the focused state. Focusing accuracy is required, and the use time of the 10 Q OrpIll is lengthened to reduce stopping errors due to motor inertia.

In addition, in AP priority mode, the control system constantly monitors the rotation speed without using 20,000 rpm, which improves focusing accuracy.

On the other hand, in release priority mode, focus detection accuracy is required, but faster exposure is required, so the setting time for motor drive during release is shorter than in AP priority mode. There is.

Returning to FIG. 16(a), in step #1190, the auxiliary light emitting device (13) is set to 0FFI, and the display is set to 0FFI.
FF (#1190.#1195). Next, a mirror-up start signal and an aperture control signal are output to the exposure control circuit to perform mirror-up and aperture control to a predetermined value Av, and wait for the mirror-up to be completed (#1200 to #
1210). When the mirror up, which takes about 50m5ec, is completed, a motor stop signal is output, the motor waits for 10m5ec, and interrupts are prohibited.
An exposure start signal is output to start the first act.

(#12!5~l 230). Then, the exposure time Tv is measured, and when it reaches a predetermined Tv, an exposure end signal is output and waits for the second act to close (#235 to #I240).

Next, proceeding to FIG. 6(b), the microcomputer (1) outputs a 1-frame winding start signal in step #1243 to cause the film to be wound by 1 frame.

If it is determined in step #1245 that the continuous shooting mode is not set, the terminal (OP3) is set to "L" level to disable timer interrupts, the quick shooting flag is reset, and step #
Proceed to 1275. On the other hand, if it is determined that the mode is continuous shooting mode, the terminal (OP3) is set to rHJ level to interrupt the timer, the quick shooting flag is set, and step #1250 is reached.
Proceed to.

Then, in step #I245, it is determined whether or not the continuous shooting mode is selected, and if it is not the continuous shooting mode, the terminal (OF2) is connected to rLJ.
to prevent continuous shooting, and proceed to step #I275. On the other hand, if it is in the exposure mode, step #124
At step 7, set the terminal (OF2) to the "■ (" level) and output a timer start signal to the timer circuit (I5) in Figure 1.Next, when the focus flag is not set or the focus zone is not entered. In some cases, in order to drive only the remaining count value of the drive counter ENZCNT, counter interrupts and timer interrupts are enabled and the motor is driven in step #I2.
Proceed to 75 (#1250.#1255.#1265, #
1270). If AP is completed during this period and the focus is achieved, step #885 to step #I275 in FIG.
Return to step #1275 and loop.

When the focus flag (focus F) is set and the camera is within the focus zone, the focus is displayed in step #1260, and then the process proceeds to step #I275, where it waits for the mirror to be lowered (#1250 to #I260). .#1275).

When the mirror down is completed, a signal is output to stop the lens drive motor, and it takes 20m5 for the lens drive motor to stop.
Wait for ec, reset the flags other than the tracking flag and the continuous shooting flag, enable the release interrupt, and proceed to step #5 in Figure 2.
Also applies to CDINT flows of 5 or less (#1280~
#1295). However, steps #1280 and #1285 are not necessarily necessary here, and it is sufficient to return to CDINT while driving the lens.

In this embodiment, when continuous shooting mode is set,
If the release button is pressed repeatedly, the terminal (O
F2) reaches the rHJ level, the timer circuit (15) starts measuring time, and when the predetermined time elapses, the rLJ changes from the "■I" level.
The signal that replaces the level is the terminal (INT4) of the microcontroller (1).
) is entered. When this is input, the microcomputer (1) again starts the interrupt from step #1297 in FIG. 16(a), and the timer circuit (15)
(Connect the “L” level signal to the terminal (OF2)
Then, the release flow from step #100O is performed in the same manner.

Next, the flow of the termination interrupt shown in FIG. 20 will be explained. This is the processing flow when the lens reaches the end of the lens without detecting a sufficient contrast level for focus detection while driving the lens and detecting the contrast of the subject during low-contrast scanning. It is.

Detection of this termination is performed by placing a switch (S) on both ends of the lens (not shown).
7) is provided, and this switch (S7) switches ON1, .
3), a signal changing from the white 4 level to the rLJ level is input, and the microcomputer (1) carries out the flow of the termination interrupt shown in FIG. In this flow, first step #l350
The motor is stopped at step #1355, and it is determined whether the flag LBF for retracting the lens is set. If it is not set, it means that the lens has reached the end with the lens extended, and the flag LBF for retracting the lens is determined at step #1360. This flag LBF' is set, and the reversal drive is started in step #l365, and the process proceeds to the CDINT flow in FIG. Since contrast detection is impossible because it has been reached, step #1
At 370, the microcomputer (1) displays an indication that it is disabled.

Next, a modified example will be shown. The contents of the modified example are as follows.

l) 20. of the motor in release priority mode during release. Eliminate OOO rpm and reduce stopping error.

2) During AFfi destination mode during release, within a predetermined time,
When the count value of the drive counter ENZCNT does not become 0, the release is locked.

3) When waiting for AF priority mode during release and in accuracy priority mode, the speed of the motor is only looOrpm, and release is possible only when the count value of drive counter ENZCNT becomes 0, and if it does not become 0, release is locked. to improve focusing accuracy.

A modification resulting from the above changes is shown in FIG. 22 and will be described.

First, the change associated with (1) deletes steps #1095 to #1I07 in FIG. 16(a).

This is because 20 OOO rpm (high speed) is lost (see Figure 22). In addition to this, steps #l745 and #2730 in FIG. #2735
These high-speed modes are not available during release, so they are deleted (not shown). Furthermore, step #255 in the flow of INTEVENT
5. #2570. Delete #2575.

Next, the change associated with (2) is that between step #1150 and step #l 160 in FIG. If the number exceeds 148, the process advances to step #1170, resets the release flag RESF, and returns. To explain this value 148 with reference to Table 3, it takes eomsec to reach the number of pulses 28, so from 150 m5ec to 6
90m5ec minus 0m5ec is the time that can be driven at 500Orpm, and the number of pulses that can be driven is 4/3
X90=120, and adding the above 28 results in 148.

The change associated with (3) is that after step #1125 in FIG. 16(a), a determination step is provided as step #l 130 to determine whether or not the accuracy priority mode is selected. , the process advances to step #1145 to prohibit modes of 11,000 rp or more. Also, step #1
After step 150, a step #1152 is provided to determine whether or not the accuracy priority mode is set, and when the accuracy priority mode is set, the count value of the drive counter ENZCNT is 40 or less (150m5ecX4/I5(IQ
Step # of determining whether or not QOrpm))
l 153 and if it is 40 or less, +00Orp
The process advances to step #1175 to set the flag flF instructing m drive, and the subsequent processing is performed. If it exceeds 40, release flag RE is set in step #l170.
Reset SF and return. Step #1152
If it is not the accuracy priority mode, the process advances to step #1155 and the subsequent flow is performed.

Effects of the Invention According to the above configuration, even if the camera is in the AF priority mode, in the snapshot mode, the second and subsequent snapshots are focused in the AP operation during the previous release even if the focus is not completed. If this is remembered, the current shirt taller is possible. Therefore, when several subjects enter the shooting frame in succession, it is possible to take a picture even if the subject at the back is slightly out of focus, and it is possible to obtain the picture as the photographer intended. We can provide the best possible camera.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 2 is a flowchart showing the operation of the device shown in FIG. 1, FIG. 3 is a graph showing the offset of the event counter of the focus detection device, and FIGS. Fig. 20 is a flowchart showing the operation of the device shown in Fig. 1, Fig. 21 is a time chart showing the relationship between whether movement integration is possible or not and motor drive control, and Figs. 22 and 23 show modified examples. Flowchart, 2nd
4 and 25 are diagrams showing the principle of focus detection, Figures 26 and 27 are diagrams showing the principle of conventional tracking correction, and Figures 28 to 31 are diagrams showing the principle of tracking correction of the present invention. It is a diagram. l...Microcomputer, 2...Exposure control circuit, 3...Photometering circuit, 10...Motor control circuit, 11...Encoder, 12...Inner lens circuit, 13...Auxiliary light generator , 15'...timer. Patent applicant: Minolta Camera Co., Ltd. Agent: Two patent attorneys (Figure 2 (b)) 1! Figure '7 Figure 8 Figure 9m Tomi 11 Figure 15 Figure 316 (b) Figure 17 Figure 21 Figure 25 Figure Fox -s RIII, m Page 30 1131 Figure

Claims (1)

[Claims] (1) A focus detection means that calculates and detects the focus position, a means that sets the lens to the focus position according to the calculation result, and a continuous shooting operation while the release button is continuously pressed. The camera includes a control means for repeatedly performing an automatic focus adjustment operation at a predetermined cycle, and an automatic focus priority control means for controlling the camera so that the release operation is not performed unless the lens has completed focusing even if the release operation is performed. in a camera set to continuous shooting mode, a focus failure detection means detects that focus detection is impossible or the amount of defocus is large as a result of a focus detection calculation performed by the focus detection means; A storage means that remembers that the camera was in focus the last time the shutter was released, and a memory device that stores the fact that it was in focus when the camera was released the previous time, and a lens that does not adjust the lens if it is unable to detect focus or has a large amount of defocus at the time of shooting this time, and that it was in focus at the time of the camera's previous release. A camera equipped with a focus detection device, characterized in that it is equipped with means for permitting release.