JPH06148510A - Camera with line-of-sight detector - Google Patents

Abstract

PURPOSE:To select a focus signal with the latest line-of-sight information by eliminating the lowering of a frame speed at the time of continuous shots. CONSTITUTION:This camera is provided with a selector means PRS for selecting at least one focus signal from a plurality f focus signals obtained from a focus detector means SNS, PRS on the basis of line-of-sight information obtained from line-of-sight detector means CCD, YLED, YDR and the line-of-sight detection control means PRS for operating the line-of-sight detector means to carry out at least once line-of-sight detecting operation at the time of awaiting the completion of preparation operation for photographing during continuous shots at the time of continuous shot photographing, and the line-of-sight detector means is operated to carry out at least once line-of-sight detecting operation at the time of awaiting the completion of preparation operation for photographing, such as awaiting the completion of driving a lens or awaiting the completion of feeding a film during continuous shots, in other words, after the second frame of continuous shots at the time of continuous shot photographing.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a visual line having a visual line detecting means for detecting the gaze direction of a photographer looking into the viewfinder and a focus detecting means for repeatedly detecting the focal states of a plurality of subject areas on the screen. The present invention relates to improvement of a camera with a detection function.

[0002]

2. Description of the Related Art Conventionally, the line-of-sight direction of a photographer is detected,
Which area (position) the photographer is observing in the viewfinder, the so-called gaze direction of the photographer is detected by the line-of-sight detecting means provided in a part of the camera, and automatic focusing is performed based on the signal from the line-of-sight detecting means. Various cameras have been proposed that control various shooting functions such as adjustment and automatic exposure.

For example, Japanese Patent Application Laid-Open No. 61-61135 proposes a camera in which the distance measuring direction of the focus detecting device is controlled based on the output from the line-of-sight detecting means to adjust the focus state of the photographing system. ing.

Further, the applicant of the present application has filed Japanese Patent Laid-Open No. 1-24151
In Japanese Patent Publication No. 11, gaze detecting means for detecting the gaze direction of the photographer, focus detecting means having a plurality of distance measuring fields,
A camera having automatic exposure control means having a plurality of photometric sensitivity distributions and controlling the drive of the focus detection means and the automatic exposure control means based on the output signal from the line-of-sight detection means is proposed. .

As an autofocus mode provided in a conventional camera, there is a one-shot mode in which focus detection is performed until the photographic lens is in focus and once focus is achieved, focus detection is not performed thereafter. There are two servo modes that continue to perform focus detection regardless of the focus state of the taking lens.

The operation in the one-shot mode in the camera equipped with the above-mentioned line-of-sight detecting means is as follows.

First, when the switch SW1 is turned on by the first stroke of the release button, the gaze point in the viewfinder of the photographer is obtained by the line-of-sight detecting means before focus detection. As the procedure at this time, first, the sensor is accumulated and the image signal is read out. Then, the line-of-sight direction of the photographer is obtained from the image signal. Next, which part in the viewfinder is focused from the line-of-sight direction, that is, the gazing point is obtained. This gazing point is represented by coordinates in the viewfinder. Then, it is a mechanism for determining a distance measuring point corresponding to the coordinates in the finder.

Then, the focus state is detected by the focus detecting means with respect to the distance measuring point thus obtained by the line-of-sight detecting means,
The photographing lens is driven to the in-focus position based on the information.

Once the focus detection point is determined by the line-of-sight detection means, the focus operation is performed by focusing on only the focus state of the focus detection point until the focus is achieved.

In the one-shot mode, the line of sight is not detected during the release operation (including, of course, continuous shooting) because the release is not possible unless the subject is in focus.

The operation in the servo mode of the camera equipped with the line-of-sight detecting means is as follows.

As in the one-shot mode, the switch S
Immediately after W1 is turned on, the line-of-sight detecting means is executed to determine the distance measuring point. After that, the lens is driven, that is, the focusing operation is performed based on the information of the focus detection calculation of the distance measuring point.

Like the one-shot mode in the servo mode, the line-of-sight detection is not performed during the release operation (including, of course, continuous shooting).

[0014]

By the way, in the camera as described above, for example, in the servo mode, since the subject is often moving, there is a case where it is desired to change the composition while focusing. Further, since the subject is small and often moves, the subject may deviate from the focus detection point determined by the line-of-sight detecting means to another focus detection point.

Therefore, it is necessary to repeatedly extract the gazing point of the photographer at a certain interval, continue to detect the focus state of the area each time, and drive the photographing lens based on the information.

However, when the camera as described above is realized, when the line-of-sight detecting means for detecting the gazing point of the photographer is operated, the line-of-sight detecting sensor is accumulated and read out, the line-of-sight direction is calculated, and the gaze point is extracted. It took a considerable amount of time to execute the series of steps. Therefore, particularly during continuous shooting, there is a problem that the frame speed decreases.

(Object of the Invention) An object of the present invention is to provide a camera with a line-of-sight detection function which can select a focus signal based on the latest line-of-sight information while avoiding a decrease in frame speed during continuous shooting. That is.

[0018]

SUMMARY OF THE INVENTION The present invention includes a line-of-sight detecting means for detecting the gaze direction of a photographer looking into the viewfinder, and a focus detecting means for repeatedly detecting the focus state of a plurality of subject areas on the screen. Selection means for selecting at least one focus signal based on the line-of-sight information obtained by the line-of-sight detection means from among the plurality of focus signals obtained by the focus detection means, and the focus signal selected by the selection means. A lens driving means for driving a photographing lens based on the above, and a line-of-sight detection control for operating the line-of-sight detecting means to perform at least one line-of-sight detection operation while waiting for completion of a shooting preparation operation during continuous shooting during continuous shooting. Means is provided during continuous shooting, that is, during continuous shooting, that is, while waiting for the completion of shooting preparation operations such as waiting for lens driving completion and film feeding completion for the second and subsequent frames of continuous shooting. And so as to perform at least one of the line-of-sight detection operation by operating the detection means.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below based on the illustrated embodiments.

FIG. 1 is a view showing the schematic arrangement of a focus detection system of a camera according to an embodiment of the present invention.

In FIG. 1, MSK is a visual field mask having a cross-shaped opening MSK-1 in the center and vertically long openings MSK-2 and MSK-3 in the peripheral portions on both sides. F
LDL is a field lens and corresponds to the three openings MSK-1, MSK-2, and MSK-3 of the field mask MSK, and includes three parts FLDL-1, FLDL-2, and FL.
Made of DL-3. DP is a diaphragm, and a total of four apertures DP-1a and DP- are provided in the central portion, one pair each in the vertical and horizontal directions.
1b, DP-4a, DP-4b, and a pair of openings DP-2a, DP-2b and DP- on the left and right peripheral portions.
3a and DP-3b are provided respectively. Areas FLDL-1, FLDL of the field lens FLDL
-2 and FLDL-3 are these aperture pairs DP-
1, DP-2, DP-3 have the function of forming an image near the exit pupil of an objective lens (not shown). The AFL is composed of four pairs of eight lenses AFL-1a, AFL-1b, AFL-4a,
AFL-4b, AFL-2a, AFL-2b, AFL-
The secondary imaging lens 3a and AFL-3b is provided behind the aperture DP corresponding to each aperture. The SNS has four sensor rows SNS-1a, SN in four pairs.
S-1b, SNS-4a, SNS-4b, SNS-2
a, SNS-2b, SNS-3a, SNS-3b, which are arranged so as to receive the image corresponding to each secondary imaging lens AFL.

In the focus detection system shown in FIG. 1, when the focus of the objective lens (photographing lens) is in front of the film surface, the subject images formed on each pair of sensor rows are close to each other, and , The subject images are separated from each other. Since the relative position displacement amount of the subject image has a specific functional relationship with the defocus amount of the photographing lens, if an appropriate calculation is performed for each sensor output in each sensor row pair, the defocus amount of the photographing lens, A so-called defocus amount can be detected.

By adopting the configuration described above, for an object in which the light amount distribution changes only vertically or horizontally in the vicinity of the center of the range photographed or observed by the objective lens (not shown). It is also possible to measure the distance, and the opening MSK around the field mask other than the center
Distance can be measured even for an object located at a position corresponding to −2, MSK-3.

FIG. 2 is a diagram showing an optical arrangement of a camera having a focus detection device having the focus detection system of FIG.

In FIG. 2, LNS is a zoom photographing lens, QRM is a quick return mirror, FSCRN is a focusing screen, PP is a pentaprism, EPL is an eyepiece, and FPL is an eyepiece.
PLN is a film surface, SM is a sub-mirror, MSK is a field mask, ICF is an infrared cut filter, FLDL is a field lens, RM1 and RM2 are first and second reflection mirrors, SHMSK is a light-shielding mask, DP is a diaphragm, and AFL is AFL. Two
Next imaging lens, AFP is reflective surface AFP-1 and exit surface AF
Prism member having P-2, SNS is cover glass S
The sensor has an NSCG and a light-receiving surface SNSPLN.

The prism member AFP has a reflection surface AFP-1 on which a metal reflection film such as aluminum is deposited, and has a function of reflecting the light beam from the secondary imaging lens AFL and deflecting it to the emission surface AFP-2. Have

FIG. 3 is a circuit diagram showing a specific example of the structure of a camera equipped with the focus detection device as shown in FIGS. 1 and 2. First, the structure of each part will be described.

In FIG. 3, PRS is a control device of the camera, for example, a CPU (central processing unit), a ROM,
It is a one-chip microcomputer (hereinafter referred to as a microcomputer) having a RAM and an A / D conversion function. Microcomputer P
The RS performs a series of camera operations such as an automatic exposure control function, an automatic focus adjustment function, and film winding and rewinding in accordance with the camera sequence program stored in the ROM. For that purpose, the microcomputer PRS uses the communication signal SO,
SI, SCLK, communication selection signals CLCM, CSSDR, C
The DDR is used to communicate with peripheral circuits in the camera body and the control device in the lens to control the operation of each circuit and the lens.

SO is a data signal output from the microcomputer PRS, SI is a data signal input to the microcomputer PRS, and SCLK is a synchronous clock of the signals SO and SI.

LCM is a lens communication buffer circuit,
When the camera is operating, power is supplied to the lens power supply terminal VL and the selection signal CL from the microcomputer PRS is supplied.
When the CM is at a high potential level (hereinafter referred to as "H" and a low potential level is referred to as "L"), it serves as a communication buffer between the camera and the lens.

When the microcomputer PRS sets the selection signal CLCM to "H" and sends out predetermined data as a signal SO in synchronization with SCLK, the buffer circuit LCM causes each of SCLK and SO via the camera-lens communication contact. Of the buffer signals LCK and DCL are output to the lens LNS. At the same time, the buffer signal of the signal DLC from the lens LNS is output as a signal SI, and the microcomputer PRS inputs the signal SI as lens data in synchronization with SCLK.

DDR is a switch detection and display circuit, which is selected when the signal CDDDR is "H", and SO, SI,
It is controlled from the microcomputer PRS using SCLK. That is, the display of the display member DSP of the camera is switched based on the data sent from the microcomputer PRS, and ON / OFF states of various operation members of the camera are notified to the microcomputer PRS by communication.

SW1 and SW2 are switches interlocked with a release button (not shown). SW1 is turned on when the release button is pressed in the first step, and then S1 is pressed when the release button is pressed in the second step.
W2 turns on. Microcomputer PRS is photometric with SW1 ON,
Automatic focus adjustment is performed, and exposure control and subsequent film winding are performed using SW2ON as a trigger.

The switch SW2 is a microcomputer P
It is connected to the "interrupt input terminal" of RS, and an interrupt is generated by SW2ON even while the program is running when SW1 is ON, and control can be immediately transferred to a predetermined interrupt program.

MTR1 is a film feeding motor, MTR2 is a motor for mirror up / down and shutter spring charging, and forward / reverse control is performed by respective drive circuits MDR1 and MDR2. Microcomputer PRS to MDR
1, signals M1F, M1R, M input to MDR2
2F and M2R are signals for motor control.

MG1 and MG2 are shutter front and rear curtain running start magnets, which are energized by signals SMG1 and SMG2 and amplifying transistors TR1 and TR2, respectively, and are connected to the microcomputer P.
Shutter control is performed by RS.

The switch detection and display circuit DD
R, motor drive circuits MDR1, MDR2, and shutter control are not directly related to the present invention, and thus detailed description thereof will be omitted.

LPRS is an in-lens control circuit, and the circuit L
The signal DCL input to the PRS in synchronism with LCK is the command data from the camera to the taking lens LNS,
The operation of the lens in response to a command is predetermined. The control circuit LPRS analyzes the command according to a predetermined procedure, and performs focus adjustment and aperture control operations, and the operation status of each part of the lens (drive status of the focus adjustment optical system, drive status of the aperture, etc.) and various types at the output DLC. Parameters (open F number, focal length, coefficient of defocus amount versus movement amount of focus adjustment optical system, etc.) are output.

In this embodiment, an example of a zoom lens is shown, and when a focus adjustment command is sent from the camera,
The focus adjustment motor LTRM is driven by the signals LMF and LMR according to the drive amount and direction sent at the same time,
Focus adjustment is performed by moving the focus adjustment optical system in the optical axis direction. The amount of movement of the optical system is detected and controlled by the pulse signal SENCF of the encoder circuit ENCF that detects the pattern of the pulse plate that rotates in conjunction with the optical system with the photo coupler and outputs the number of pulses according to the amount of movement. The control circuit LPRS itself sets the signals LMF and LMR to "L" when the count value is counted by the counter in the circuit LPRS and the count value matches the movement amount sent to the control circuit LPRS.
To control.

Therefore, once the focus adjustment command is sent from the camera, the microcomputer PRS, which is the camera control device, does not need to be involved in the lens driving at all until the lens driving is completed. Also, the contents of the counter can be sent to the camera when requested by the camera.

When an aperture control command is sent from the camera, a stepping motor DMTR known for driving the aperture is driven in accordance with the number of aperture steps sent at the same time. Since the stepping motor can be open-controlled, it does not need an encoder for monitoring the operation.

ENCZ is an encoder circuit attached to the zoom optical system, and control circuit LPRS is an encoder circuit E.
The signal SENCZ from NCZ is input to detect the zoom position. Lens parameters at each zoom position are stored in the control circuit LPRS, and when a request is made from the microcomputer PRS on the camera side, the parameter corresponding to the current zoom position is sent to the camera.

SPC is a photometric sensor for exposure control that receives light from a subject through a taking lens, and its output SSPC is input to an analog input terminal of the microcomputer PRS, and after A / D conversion, according to a predetermined program. Used for automatic exposure control.

SDR is a line sensor device SN for focus detection
It is a drive circuit for S and is selected when the signal CSDR is "H" and uses the SO, SI and SCLK to control the microcomputer PR.
Controlled from S.

The signals φSEL0 and φSEL1 supplied from the drive circuit SDR to the sensor device SNS are the signals SEL0 and SEL1 from the microcomputer PRS, and φSEL0 =
When "L" and φSEL1 = "L", the sensor array pair SNS-
1 (SNS-1a, SNS-1b), φSEL0 =
When "H" and φSEL1 = "L", the sensor array pair SNS-
4 (SNS-4a, SNS-4b), φSEL0 =
When "L" and φSEL1 = "H", the sensor array pair SNS-
2 (SNS-2a, SNS-2b), φSEL0 =
When "H" and φSEL1 = "H", the sensor array pair SNS-
3 (SNS-3a, SNS-3b).

After the accumulation is completed, SEL0 and SEL1 are appropriately set, and then clocks φSH and φHRS are sent, so that SEL0 and SEL1 (φSEL0, φSE
The image signals of the sensor array pair selected in L1) are sequentially output from the output VOUT serially.

VP1, VP2, VP3 and VP4 are sensor column pairs SNS-1 (SNS-1a, SNS-1), respectively.
b), SNS-2 (SNS-2a, SNS-2b), S
NS-3 (SNS-3a, SNS-3b), SNS-4
A monitor signal from a subject brightness monitor sensor arranged in the vicinity of (SNS-4a, SNS-4b) causes the voltage to increase with the start of accumulation, whereby the accumulation control of each sensor array is performed.

Signals φRES and φVRS are sensor reset clocks, φHRS and φSH are image signal read clocks, and φT1, φT2, φT3, and φT43 are clocks for ending the accumulation of each sensor column pair.

Output VIDEO of sensor drive circuit SDR
Is the image signal amplified by the gain determined by the brightness of the subject after taking the difference between the image signal VOUT from the sensor device SNS and the dark current output. The dark current output is the output value of the light-shielded pixel in the sensor array, and the SDR holds the output in the capacitor by the signal DSH from the microcomputer PRS and performs differential amplification between this and the image signal. The output VIDEO is input to the analog input terminal of the microcomputer PRS, and the microcomputer PRS, after A / D conversion of the signal, sequentially stores the digital value at a predetermined address on the RAM.

Signals / TINTE1, / TINTE2, /
TINTE3 and / TINTE4 are sensor row pairs S, respectively.
NS-1 (SNS-1a, SNS-1b), SNS-2
(SNS-2a, SNS-2b), SNS-3 (SNS
-3a, SNS-3b), SNS-4 (SNS-4a,
A signal indicating that the charge accumulated in SNS-4b) becomes appropriate and the accumulation is completed, and the microcomputer PRS receives the signal and reads the image signal.

The signal BTIME is a signal for giving a timing for determining the read gain of the image signal amplifying amplifier in the sensor drive circuit SDR. Normally, in the circuit SDR, this signal is "H".
The read gain of the corresponding sensor row pair is determined from the voltages of the monitor signals VP0 to VP3 at the time.

CK1 and CK2 are the above clock φRES,
It is a reference clock given from the microcomputer PRS to the sensor drive circuit SDR in order to generate φVRS, φHRS, and φSH.

The microcomputer PRS sets the communication selection signal CSDR to "H" and sends a predetermined "storage start command" to the sensor drive circuit SDR to start the storage operation of the sensor device SNS.

As a result, the subject image formed on each sensor is photoelectrically converted by the four sensor row pairs, and electric charges are accumulated in the photoelectric conversion element portion of the sensor. At the same time, the brightness monitoring sensor signals VP1 to VP4 of the respective sensors rise, and when this voltage reaches a predetermined level, the sensor drive circuit SDR independently sets the signals / TINTE1 to / TINTE4 to "L".

In response to this, the microcomputer PRS receives the clock C
A predetermined waveform is output to K2. The sensor drive circuit SDR generates clocks φSH and φHRS based on CK2 and supplies them to the sensor device SNS, which outputs an image signal according to the clock, and the microcomputer PRS synchronizes with CK2 which itself outputs. The output VIDEO input to the analog input terminal is converted to A / by the internal A / D conversion function.
After the D conversion, the digital signals are sequentially stored in a predetermined address of the RAM.

Regarding the operation of the sensor drive circuit SDR and the sensor device SNS, the applicant of the present invention has previously described a focus detection device having two pairs of sensor arrays as disclosed in Japanese Patent Laid-Open No. 06451/1990.
No. 75, etc., so detailed description thereof will be omitted here.

As described above, the microcomputer PRS receives the image information of the subject image formed on each sensor array pair,
After that, a predetermined focus detection calculation is performed, and the defocus amount of the taking lens can be known.

The CCD is an image sensor for detecting the line-of-sight position of the photographer gazing at the finder.

YLEDs are infrared light emitting diodes for detecting the line of sight, and a plurality of YLEDs are arranged. The infrared light emitting diode YLED is irradiated toward the photographer's eye looking through the viewfinder of the camera, and the reflected light is imaged on the image sensor CCD for detecting the line of sight, and the line of sight position is based on the information such as the image formation. Is detected.

YDR is a line-of-sight position detecting interface circuit for performing control such as storage and reading of the line-of-sight detecting image sensor CCD and driving of the line-of-sight detecting infrared light emitting diode YLED in accordance with a command from the microcomputer PRS.

Next, the operation of the camera having the line-of-sight detecting device and the focus detecting device having the above-mentioned structure will be described with reference to the following flow chart.

FIG. 4 is a flowchart showing the overall operation of the extremely rough camera.

When power is supplied to each circuit shown in FIG. 3, the microcomputer PRS starts the operation from step (001) through step (000) in FIG. [Step (001)] The state of the switch SW1 that is turned on by pressing the release button (not shown) in the first stage is detected. If the switch SW1 is off, the process proceeds to step (002). Transition. [Step (002)] All flags and variables are initialized. [Step (003)] The "AE control" subroutine for photometry, state detection of various switches, display, etc. is executed.
Since this AE control is not directly related to the present invention, detailed description will be omitted. When this "AE control" subroutine is completed, the routine proceeds to step (004). [Step (004)] The "AF control" subroutine is executed. Here, the accumulation of the sensor, focus detection calculation, automatic focus adjustment operation of lens drive are performed, and the gazing point of the photographer is extracted. Details will be described later with reference to FIG. This "A
When the "F control" subroutine is completed, the step (0
Return to 01) and step (00
3) and (004) are repeatedly executed.

When power is supplied to each circuit shown in FIG. 3 and the switch SW2 is turned on while the microcomputer PRS is operating, an interrupt occurs and a release operation described later with reference to FIGS. 11 and 12 is executed.

FIG. 5 is a flowchart showing the "AF control" subroutine executed in the step (004).

When this "AF control" subroutine is called, the step (010) is followed by the step (011).
To start the operation from. [Step (011)] Switch SW1 is turned on to 1
It is determined whether or not it is the AF control for the first time. If it is the first AF control, the process proceeds to step (012), and if not, the process proceeds to step (014). [Step (012)] Initialize flags and variables for AF control. [Step (013)] The visual axis detection flag and variables are initialized. [Step (014)] Here, a "line of sight detection" subroutine is executed. In other words, in order to perform the gaze detection operation,
The gazing point is extracted from the accumulation and reading in the image sensor CCD, and the distance measuring point is determined by the line of sight. The details are shown in FIG.
See below. [Step (015)] Here, a "focus detection" subroutine is executed. That is, for the focus detection operation, each sensor pair SNS-1 (SNS-1a, SNS-1b),
SNS-2 (SNS-2a, SNS-2b), SNS-
3 (SNS-3a, SNS-3b), SNS-4 (SN
S-4a and SNS-4b) store and read out image signals, focus detection calculation, and determination of a focus detection point where the main subject is supposed to be located. The details are shown in FIGS. 6 and 7.
See below. [Step (016)] Here, a "distance measuring area selection" subroutine is executed. That is, the above step (01
The distance measuring point actually used from the distance measuring point information obtained from the "focus detection" subroutine executed in 5) and the distance measuring point information obtained from the "line of sight detection" subroutine executed in the step (014). To select. The details will be described later with reference to FIG. [Step (017)] Here, the above step (01
The defocus amount is calculated from the focus detection information of the focus detection points obtained in 6). [Step (018)] Here, a "lens drive" subroutine is executed. That is, the actual lens driving amount is obtained from the defocus amount, and the lens driving is performed if necessary.

After the lens driving is completed, step (01
This "AF control" subroutine is returned from 9).

6 and 7 are flow charts showing the "focus detection" subroutine executed in the step (015).

When this "focus detection" subroutine is called, it goes through step (110) and then step (111).
To start the operation. [Step (111)] The switch SW1 is turned on to 1
It is determined whether or not the AF control is performed for the first time. If it is the first AF control, the process proceeds to step (112). If not, the process proceeds to step (113). [Step (112)] The selected sensor is initialized. [Step (113)] Here, the "accumulation start" subroutine is executed.

The subroutine is a routine for starting the accumulation operation of the sensor, and specifically, the sensor drive circuit SD.
An accumulation start command is sent to R to start the accumulation operation of the sensor device SNS, and at the same time, each sensor accumulation end signal / TINTE1 to / TINTE from the drive circuit SDR.
4 is a sub-routine for permitting the interrupt function so that the microcomputer PRS can execute the "accumulation completion interrupt". As a result, each sensor (sensor array pair SNS-1 to S
When the storage of NS-4) is completed, each storage completion interrupt is executed.

Completion of accumulation of each sensor is signal / TINTE1
It can be detected by the fall of ~ / TINTE4, and these signals are connected to the "input terminal with interrupt function" of the microcomputer PRS. In the diagram of FIG. 6, the interrupt control is indicated by the broken line, and the signal / TIN
When an interrupt due to TE1 to / TINTE4 occurs, the control shifts to each interrupt routine shown in FIG. 7 via in FIG. Therefore, for example, the sensor array pair SNS-
If the charge accumulation of 1 becomes appropriate and the signal / TINTE1 from the sensor drive circuit SDR falls, it is possible to shift to the interrupt routine after step (150) of FIG. 8 in response to this.

The interrupt routine after step (150) in FIG. 7 is a routine for inputting the image signal of the sensor pair SNS-1.

In step (151), the sensor array pair SNS
After inputting the image signal of -1, the interrupt routine is returned at step (052). The image signal is input by the microcomputer P
The output VIDEO input to the analog input terminal of RS is serially A / D converted and the digital data is converted into a predetermined R
This is achieved by sequentially storing in the AM area.

Sensor column pair SNS-2, SNS-3, SN
Even when the accumulation of S-4 is completed, the interrupt control is similarly performed, and steps (153), (156) and (15) of FIG.
The process proceeds to 9) and the image signal of each sensor is input.

Since the "accumulation start" subroutine and the specific method of inputting the image signal are disclosed in Japanese Patent Laid-Open No. 2-064517, detailed description thereof will be omitted.

Returning to FIG. 6, the description will be continued.

Since the image signal input process of each sensor is interrupt controlled, it is preferentially processed whenever the accumulation is completed during execution of the focus detection calculation of steps (114) to (126) in the figure. Become. [Step (114)] It is determined whether the focus detection calculation of the sensor array pair SNS-1 is completed. If it is completed, the process proceeds to step (117), and if it is not completed, the step ( 115). [Step (115)] It is determined whether or not the interrupt processing of the image signal input of the sensor array pair SNS-1 is completed. If completed, the process proceeds to step (016), and if not completed, the step is completed. Proceed to (117). [Step (116)] A focus detection calculation based on the image signal of the sensor array pair SNS-1 is executed. A specific calculation method for detecting the defocus amount is described in Japanese Patent Application No. 61-16082.
Since it is disclosed in Japanese Patent Publication No. 4 etc., detailed description thereof will be omitted. [Step (117)] It is determined whether or not the focus detection calculation of the sensor array pair SNS-2 is finished. If it is finished, the process proceeds to step (120), and if it is not finished, the step ( 118). [Step (118)] It is determined whether or not the interrupt processing of the image signal input of the sensor array pair SNS-2 is completed, and if completed, the process proceeds to step (019), and if not completed, the step is completed. Shift to (120). [Step (119)] The focus detection calculation based on the image signal of the sensor array pair SNS-2 is executed. [Step (120)] It is determined whether or not the focus detection calculation of the sensor array pair SNS-3 is completed. If it is completed, the process proceeds to step (123), and if it is not completed, the step (123) is executed. 121). [Step (121)] It is determined whether the interrupt processing of the image signal input of the sensor array pair SNS-3 is completed, and if completed, the process proceeds to step (122), and if not completed, the step completed. Shift to (123). [Step (122)] A focus detection calculation based on the image signal of the sensor array pair SNS-3 is executed. [Step (123)] It is determined whether or not the focus detection calculation of the sensor array pair SNS-4 is completed. If it is completed, the process proceeds to step (126), and if it is not completed, the step (126) is executed. 124). [Step (124)] It is determined whether or not the interrupt process of the image signal input of the sensor array pair SNS-4 is completed, and if completed, the process proceeds to step (126), and if not completed, the step Move to (125). [Step (125)] A focus detection calculation based on the image signal of the sensor array pair SNS-4 is executed. [Step (126)] Here, it is determined whether or not the focus detection calculation corresponding to all the sensors is completed. If not completed, the process returns to step (114), and if all are completed. Moves to step (127).

To summarize the above, step (11
After the accumulation operation is started in step 3), the step (1
14) to (126) are repeatedly executed to sequentially perform focus detection calculation from the sensor into which the image signal is read. [Step (127)] The focus detection point where the main subject is likely to exist is selected from the calculation results of the focus detection calculation of each sensor. In the present embodiment, the criterion for determining that the subject is the main subject is the closest distance measuring point among the distance measuring sensors.

When the determination of the distance measuring points is completed, step (12)
The "focus detection" subroutine is returned in 8).

FIG. 8 shows the "visual axis detection" subroutine executed in the step (014).

When this "line-of-sight detection" subroutine is called, step (201) is followed by step (202).
To start the operation from. [Step (202)] Image sensor C for sight line detection
The CD is accumulated and read, and the line-of-sight data is read. [Step (203)] Based on the line-of-sight data read in the step (202), the line-of-sight direction of the photographer is obtained by a predetermined calculation. [Step (204)] It is determined whether or not the calculation result of the line-of-sight direction obtained in step (203) is defective. If defective, the process proceeds to step (208), and if not defective, step (205). ). [Step (205)] The gazing point in the viewfinder is obtained by a predetermined calculation from the line-of-sight direction obtained in step (203). [Step (206)] It is determined whether or not the calculation result of the gazing point obtained in step (205) is defective, and if defective, the process proceeds to step (208), and if not defective, step (207). ). [Step (207)] The distance measuring point corresponding to the gazing point obtained in the step (205) is obtained, and the step (20)
Go to 9).

Step (204) or step (2)
If it is determined in 06) that there is a defect, the process proceeds to step (208) as described above. [Step (208)] Eye-gaze detection failure flag EYEN
Set G to "1". Further, the clearing of the flag EYENG is performed in the step (202). Then, the process proceeds to step (209). [Step (209)] The "visual axis detection" subroutine is returned.

FIG. 9 is a flow chart showing the "distance measurement area selection" subroutine executed in step (016).

When this "range-finding area selection" subroutine is called, step (301) is followed by step (30
The operation from 2) is started. [Step (302)] Flag E indicating failure in sight line detection
It is determined whether YENG is "1". If "EYENG
= 0 ”, that is, if the line-of-sight detection is successful, step (30
Move to 3), and if “EYENG = 1”, step 3
Move to 04. [Step (303)] Since the line-of-sight detection is successful here, the focus detection point obtained in the above step (207), that is, the focus detection point corresponding to the gazing point of the photographer is selected. [Step (304)] Since the line-of-sight detection is unsuccessful here, the focus detection point obtained in the above step (127), that is, the focus detection point closest to the focus is selected, and the step (305) is performed. Move to. [Step (305)] The "distance measurement area selection" subroutine is returned.

FIG. 10 shows an interrupt process "release operation" which is executed when an interrupt occurs when the switch SW2 is turned on.
It is a flowchart of.

When an interrupt occurs, the operation from step (502) is started via step (501). [Step (502)] (Zoom) Photographic lens LNS
To the lens drive stop command. [Step (503)] Start driving the motor MTR2 to raise the mirror (quick return mirror QRM). This control is performed by outputting a normal rotation signal to the signals M2F and M2R and causing the motor MTR2 to rotate normally. [Step (504)] A diaphragm drive command is sent to the taking lens LNS in order to narrow down the lens. [Step (505)] This step stands by until the mirror is up, and when the mirror is up, the process proceeds to step (506). [Step (506)] Motor MT for Mirror Up
In order to stop R2, a brake signal is output to the signals M2F and M2R, and the motor MTR2 is braked (short-circuited at both ends). [Step (507)] In order to wait for the mirror to stabilize when the mirror is raised, nothing is done for a predetermined time. [Step (508)] In order to prevent the taking lens LNS from moving when the shutter control is performed, and in the aperture control performed in the step (504), the stepping motor DMTR is still energized. Therefore, in order to release this energization, a lens full drive stop command is sent to the taking lens LNS. This command is a command that has both the lens drive stop command and the stop energization stop. [Step (509)] The shutter is driven. The shutter speed at this time is A in step (003).
It is controlled by a value based on the Tv value obtained by E control. [Step (510)] A normal rotation signal is output to the signals M2F and M2R in order to start driving of the motor MTR2 in order to perform mirror down and charging of the shutter spring.
Further, the mirror down completion position and the shutter spring charge completion position are the switch CMSP1 and the switch C (not shown).
Depending on the combination of MSP2, mirror down completion position,
Check the shutter spring completion position.

Further, for this mirror down and shutter spring charge control, it is determined whether or not the mirror is up, the shutter spring charge is completed, the motor stop control, etc. during the interrupt processing every 1 ms. I do. The contents of this interrupt processing will be described later with reference to FIG. Further, the flag MRDNEND indicating the mirror-down position and the flag CGEND indicating completion of shutter spring charging are cleared. [Step (511)] Since the diaphragm of the taking lens LNS is currently in the closed state, a command to open the diaphragm is sent to the taking lens LNS in preparation for the next photometry. [Step (512)] Signals M1F and F1 are driven to drive the motor MTR1 to feed one film of film.
1R outputs a normal rotation signal.

The procedure for feeding one frame of film will be described below.

In order to know the film feed amount, a photo reflector (not shown) is provided, and the number of perforations of the film is counted by this photo reflector. Since one frame of film has eight perforations, if the film is continuously fed until eight output pulses of the photo reflector are emitted, one frame of film is fed. The output of this photo reflector is the microcomputer PRS.
It is connected to the interrupt input terminal of and the interrupt is set to occur at the rising edge of this signal. The number of times this interruption occurs is counted, and when the number of times reaches a predetermined number (8 times), it is determined that the feeding of one frame has been completed, and the film feeding is ended. The contents of this interrupt processing will be described later with reference to FIG. 10A. Also, a flag W indicating that the film feeding is completed
Clear INDEND. [Step (513)] It is determined whether or not the mirror is at the mirror down position, and the process waits at this step until the mirror is at the down position. [Step (514)] It is determined whether or not the switch SW2 is turned on, that is, whether or not continuous shooting is being performed. When the switch SW2 is ON, that is, during continuous shooting, step (51
If the switch SW2 is OFF, that is, if continuous shooting is not being performed, the process proceeds to step (521). [Step (515)] Since it is necessary to perform photometry even during continuous shooting, the "photometry" subroutine is called.

In this "photometric" subroutine, the photometric sensor SPC receives light from the subject, and the sensor SPC
Output of A is converted into A / D and used for automatic exposure control according to a predetermined program.
Calculate v and. [Step (516)] The "focus detection" subroutine described above is called in order to measure the distance even during continuous shooting. [Step (517)] It is determined whether or not the shutter spring has been charged and the film has been fed, that is, whether or not the lens can be driven. If the lens cannot be driven, step (517) Returning to 516), the "focus detection" subroutine is called again. If the lens can be driven, that is, if the charging of the shutter spring and the film feeding are both completed, the step (51
Go to 8). [Step (518)] Since the lens can be driven, the step (5) is performed on the taking lens LNS.
A command for driving the lens by the amount of pulses corresponding to the defocus amount obtained in 16) is sent. [Step (519)] Here, the "line-of-sight detection" subroutine described above is called.

The purpose of this is to find in advance the gazing point and the distance measuring point in the viewfinder of the photographer, which are necessary for the control of the next photometry and distance measuring while waiting for the end of the lens driving, and the time is lost. This is because it is suppressed as much as possible and the decrease of the piece speed is prevented. [Step (520)] It is determined whether or not the lens drive is completed. If the lens drive is not completed, the process returns to step (519) to call the "visual axis detection" subroutine again. On the other hand, if the lens driving is completed, the process proceeds to step (521). [Step (521)] It is determined whether the switch SW2 is turned on, that is, whether or not continuous shooting is being performed. If continuous shooting is in progress, the process returns to step (503) to perform the release operation again. Also, the switch SW2 is OF
F, that is, if it is determined that continuous shooting is not in progress, step (52
Go to 6).

If it is determined in step (514) that the switch SW2 is OFF, that is, that continuous shooting is not in progress, the process proceeds to step (522) as described above. [Step (522)] It is determined whether or not the charging of the shutter spring is completed. If completed, the process proceeds to step (525), and if not completed, step 52 is performed.
Move to 3. [Step (523)] Here, it is determined whether or not the film feeding is completed, and if it is completed, the step (5)
24), and if not completed, returns to step 522. [Step (524)] It is again determined whether or not the charging of the shutter spring is completed. If completed, the process proceeds to step (526), and if not completed, the process waits in this step until completed. And step (526)
Move to. [Step (525)] Similar to step (523),
It is determined whether or not the film feeding is completed. If completed, the process proceeds to step (526), and if not completed, the process waits in this step until completed. Then, the process proceeds to step (526).

That is, the above steps (521) to (52)
In 4), the process waits until the charging of the shutter spring and the film feeding are both completed, and if both are completed, the process proceeds to step (526). [Step (526)] Performs various procedures for ending interrupt processing, initialization of some variables, flags, etc.,
Returning to step (001) in FIG.

Next, a description will be given of the processing of the interrupt generated by the rising edge of the output of the photo reflector (not shown) during the film feeding control.

FIG. 12 is a flow chart showing the operation of the interruption process "film control".

When an interrupt occurs, step (601)
After that, the operation from step (602) is started. [Step (602)] It is determined whether or not the feed amount for one frame of film has been reached, that is, whether or not the interrupt processing has been performed for the eighth time, and if one frame has not been reached, the process proceeds to step (606). If the film has reached one frame, the process proceeds to step (603). [Step (603)] A brake signal is output to the signals M1F and M1R in order to quickly finish the film feeding. [Step (604)] A flag WINDOWD indicating that the film feeding for one frame is finished is set to "1" and the fact that the film feeding is finished is stored. [Step (605)] A stable film feeding interrupt is prohibited so that an interruption occurs at the rise of the photoreflector output, and a procedure for ending the film feeding control is performed. [Step (606)] This interrupt processing "film control" is returned.

Next, at the time of shutter spring charge control, 1 is set.
The interrupt processing of the interrupt generated every ms will be described.

FIG. 13 is a flow chart showing the operation of the interrupt processing "charge control".

When an interrupt occurs, step (701)
After that, the operation from step (702) is started. [Step (702)] It is determined whether or not the mirror is currently in the mirror down position. If it is not in the mirror down position, the process proceeds to step (704), and if it is in the mirror down position, the process proceeds to step (703). [Step (703)] The flag MRDNEND indicating the mirror-down position is set to "1" to store that the mirror-down position is present. [Step (704)] It is determined whether or not it is at the shutter charge completion position, and if it is not the shutter spring charge completion position, the process proceeds to step (708), and if it is the shutter spring charge completion position, the process proceeds to step (705). To do. [Step (705)] A brake signal is output to the signals M2F and M2R in order to quickly stop the motor drive. [Step (706)] The flag CGEND indicating the completion of the shutter spring charging is set to "1" to store the completion of the shutter spring charging. [Step (707)] In Step (509), 1
A procedure for prohibiting the interrupt generated every ms and ending the charge spring charge control and the mirror down control is performed. [Step (708)] This interrupt processing "charge control" is returned.

According to this embodiment, when continuous shooting is selected, preparation for shooting such as waiting for lens driving completion, film feeding completion waiting, and mirror-up completion waiting after the second frame of shooting is completed. Since the line-of-sight detection means is operated again to detect the line-of-sight while waiting for the end of the operation, it is possible to prevent the frame speed from decreasing during continuous shooting while using the latest line-of-sight information for focus adjustment. Therefore, it is possible to eliminate the problem of missing a photo opportunity.

[0101]

As described above, according to the present invention,
Line-of-sight detection means for detecting the gaze direction of the photographer looking into the viewfinder, focus detection means for repeatedly detecting the focus state of a plurality of subject areas in the screen, and a plurality of focus signals obtained by the focus detection means Selection means for selecting at least one focus signal based on the line-of-sight information obtained by the line-of-sight detection means, and a lens driving means for driving the photographing lens based on the focus signal selected by the selection means, During continuous shooting, a line-of-sight detection control unit that operates the line-of-sight detection unit to perform at least one line-of-sight detection operation while waiting for the completion of the shooting preparation operation during continuous shooting is provided. That is, at least once after the completion of the shooting preparation operation such as waiting for lens driving completion and film feeding completion waiting for the second and subsequent frames of continuous shooting, the line-of-sight detecting means is operated. So that to execute the linear detection operation.

Therefore, it is possible to select the focus signal based on the latest line-of-sight information while eliminating the decrease in frame speed during continuous shooting.

[Brief description of drawings]

FIG. 1 is a perspective view showing a focusing optical system of a camera according to an embodiment of the present invention.

FIG. 2 is a diagram showing an optical arrangement of a camera including the focusing optical system of FIG.

FIG. 3 is a block diagram showing a circuit configuration of a camera according to an embodiment of the present invention.

FIG. 4 is a flowchart showing a schematic operation of the camera of one embodiment of the present invention.

5 is a flowchart showing the "AF control" operation of FIG.

FIG. 6 is a flowchart showing the “focus detection” operation of FIG.

FIG. 7 is a flowchart showing an operation performed by an interrupt during the operation of FIG.

FIG. 8 is a flowchart showing the “gaze detection” operation of FIG.

FIG. 9 is a flowchart showing the “distance measurement area selection” operation of FIG. 5;

FIG. 10 is a flowchart showing a “release operation” performed when the switch SW2 is turned on in the embodiment of the present invention.

FIG. 11 is a flowchart showing a continuation of the operation shown in FIG.

FIG. 12 is a flowchart showing an operation of interrupt processing “film control” in one embodiment of the present invention.

FIG. 13 is a flowchart showing the operation of interrupt processing “charge control” in one embodiment of the present invention.

[Explanation of symbols]

 PRS microcomputer SNS Focus detection sensor device SDR Sensor drive circuit CCD Image sensor for line-of-sight detection SPC Photometric sensor YLED Infrared light emitting diode YDR Interface circuit for line-of-sight position detection

Claims (4)

[Claims] 1. A line-of-sight detecting means for detecting a gaze direction of a photographer looking into the viewfinder, a focus detecting means for repeatedly detecting focus states of a plurality of subject regions on the screen, and the focus detecting means. Selection means for selecting at least one focus signal based on a signal obtained by the line-of-sight detection means from a plurality of focus signals, and a lens for driving the photographing lens based on the focus signal selected by the selection means With a line-of-sight detection function, which includes a drive unit and a line-of-sight detection control unit that operates the line-of-sight detection unit to perform at least one line-of-sight detection operation while waiting for completion of a shooting preparation operation during continuous shooting camera. 2. The camera with a line-of-sight detection function according to claim 1, wherein the waiting for the completion of the shooting preparation operation is the waiting for the lens driving completion. 3. The camera with a line-of-sight detection function according to claim 1, wherein the waiting for completion of the shooting preparation operation is waiting for the end of film feeding. 4. The camera with the line-of-sight detection function according to claim 1, wherein the waiting for completion of the shooting preparation operation is waiting for the completion of mirror up.