JPH09281385A - Camera with line-of-sight detection function - Google Patents

Abstract

(57) [Abstract] [PROBLEMS] To minimize a release time lag when a release button is operated for the purpose of starting a shooting operation and to have a strong shutter chance. SOLUTION: Power supply is started when a first switch means for starting a shooting preparation operation is closed, and power supply is stopped when a predetermined time elapses, and power supply means 112 and 113, While the power is being supplied,
A control means 100 for causing the visual axis detection means 14 and 101 to repeatedly perform visual axis detection is provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a first release button.
The first switch means for starting the photographing preparation operation that is closed by pressing up to the second stage, the second switch means for starting the shooting operation that is closed by pressing the release button up to the second step, and detecting the line of sight. The present invention relates to an improvement of a camera with a visual line detection function, which includes a visual line detection means.

[0002]

2. Description of the Related Art Conventionally, various devices (for example, eye cameras) for detecting a so-called line of sight (visual axis) for detecting a "position on an observing surface" observed by an observer have been provided.

As a method of detecting the line of sight, for example, in Japanese Unexamined Patent Publication No. 1-274736, a parallel light flux from a light source is projected onto the anterior segment of an eyeball of an observer to form a corneal reflection image by reflected light from the cornea. The visual axis is obtained by using the imaging position of the pupil.

Further, which region (position) in the finder field of view the observer is observing, 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 from this line-of-sight detecting means. Various cameras have been proposed in which various photographing functions such as automatic focus detection and automatic exposure are controlled on the basis of the signal.

For example, in Japanese Patent Laid-Open No. 61-61135, the signal projection direction for focus detection is controlled based on the output from the line-of-sight detection means, and the focus state of the photographing system is adjusted by measuring the distance. A camera that has been proposed is proposed.

Further, in Japanese Patent Laid-Open No. 1-241511, a line-of-sight detecting means for detecting a gaze direction of a photographer, a focus detecting means having a plurality of distance measuring (focus detecting) fields of view, and a plurality of photometric sensitivity distributions. And an automatic exposure control unit having the above-mentioned, and the camera which controls the drive of the focus detection unit and the automatic exposure control unit based on the output signal from the line-of-sight detection unit is proposed.

In the above-mentioned line-of-sight detecting means, the reflected light from the eyeball is received by the area image sensor consisting of several thousand pixels, the image signal is read out, and the feature from the eyeball image is extracted.

Further, in the autofocus operation of the autofocus camera incorporating the above-mentioned line-of-sight detecting means, when the switch SW1 which is turned on by lightly pressing the release button is turned on, the line-of-sight detecting means is used to detect the viewfinder of the photographer before focus detection. It seeks the point of gaze inside.

In this procedure, the eyeball illuminating light of the line-of-sight detecting means is emitted, the reflected light from the eyeball is received by the area image sensor and accumulated, and then the image signal is read to obtain the line-of-sight direction of the photographer. Then, 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 finder, and the corresponding distance measuring point (focus detection point) is determined from this coordinate.

More recently, a device has been devised to detect the line of sight at high speed while maintaining high accuracy.

[0012] For example, in an autofocus camera equipped with a line-of-sight detecting means, a servo mode, which is a focusing operation mainly used when photographing a moving subject, repeatedly performs focus detection and lens driving at predetermined intervals, Focus.

At this time, the range-finding point to be focused is determined by repeatedly detecting the line of sight, but in the second and subsequent line-of-sight detection operations, the eyeball position on the area image sensor can be known from the previous line-of-sight detection result. A method of limiting an area for reading an image signal on the area image sensor has been considered.

[0014]

The above-mentioned conventional example is the use of the line-of-sight detection device in a camera, and operates and controls the function mounted in the camera according to the line-of-sight detection information.

At this time, the gaze detecting device is required to have a high speed. This is because, for example, in an application to a focus detection device, it is necessary to instantly adjust the focus to a region (portion) intended by the photographer in the photographing screen.

However, in the conventional autofocus camera equipped with the visual axis detecting device, when the release button is pressed, the visual axis is detected before the focus adjustment, so that the photographer intends to release the release button to the end. Despite pressing the button, it took time to focus, and there was a feeling of discomfort compared to when the line-of-sight detection was not performed, and it was difficult to capture a photo opportunity, and it was not possible to use it with confidence.

(Object of the Invention) A first object of the present invention is to provide a camera with a line-of-sight detection function that minimizes a release time lag when a release button is operated to start a photographing operation and is strong against shutter chances. To do.

A second object of the present invention is to perform a photographing process with substantially the same responsiveness as in the case of automatically determining the focus detection position and proceeding with the photographing process even when the focus detection position is selected by the line of sight. It is to provide a camera with a line-of-sight detection function that can advance.

[0019]

In order to achieve the first object, the present invention according to claim 1 provides a first release button.
The first switch means for starting the photographing preparation operation that is closed by pressing up to the second stage, the second switch means for starting the shooting operation that is closed by pressing the release button up to the second step, and detecting the line of sight. In a camera with a line-of-sight detection function including line-of-sight detection means, power supply is started when the first switch means is closed, and power supply is stopped after a lapse of a predetermined time. While the power is being supplied, a control means for causing the visual axis detecting means to repeatedly perform visual axis detection is provided, and the first switch means for starting the photographing preparation operation is closed to supply power. By doing so, the visual axis detection operation is repeatedly performed, and while the power is being supplied, the focus detection position at which the visual axis is input is continuously monitored, and when the second switch means is closed, the image is taken immediately. motion And to be able to start. In other words, even if the first switch means is closed again to perform the photographing operation, the visual axis detection means is not newly activated from the beginning, but repeated visual axis detection is performed while power is being supplied. At the same time, the accumulation time and the calculation processing time for detecting the line of sight at this time are shortened.

Similarly, in order to achieve the above first object,
According to a second aspect of the present invention, there is provided a first switch means for starting the photographing preparation operation which is closed by pressing the release button up to the first stage, and an imaging operation which is closed by pressing the release button up to the second stage. In a camera with a line-of-sight detection function, which includes a second switch unit for starting and a line-of-sight detection unit for detecting a line of sight, when the first switch unit is closed, a timekeeping operation is started and is predetermined. A timer means for ending the operation after the time is counted, and a control means for causing the eye-gaze detecting means to repeatedly perform the eye-gaze detection while the time-measuring means is performing the time-of-day preparatory operation start. First of
After the switch means is closed, the visual axis detection operation is repeatedly performed for a predetermined time, and during this predetermined time, the focus detection position at which the visual axis is input is continuously monitored and the second switch means When it is closed, the shooting operation can be started immediately. That is, even if the first switch means is closed again to perform the shooting operation,
Instead of newly operating the line-of-sight detection means from the beginning,
The line-of-sight detection is repeatedly performed during a predetermined time, and the accumulation time for the line-of-sight detection at this time and the calculation processing time are shortened.

In order to achieve the second object,
According to a third aspect of the present invention, there is provided a first switch means for starting a photographing preparation operation which is closed by pressing the release button up to the first step, and an imaging operation which is closed by pressing the release button up to the second step. In a camera with a line-of-sight detection function, which includes a second switch unit for starting and a line-of-sight detection unit for detecting a line of sight, the first switch unit is closed so that the line-of-sight detection unit has a predetermined interval. To repeatedly perform line-of-sight detection, and when this repeated line-of-sight detection is being performed,
When the first switch means is closed again, the focus detection position is determined by using the result of the line-of-sight detection performed immediately before, the focus detection information is calculated, and the adjustment is performed based on this. In most cases, when the first switch means is closed again, the release button is pressed at once all at once until the second switch means is closed.
In other words, since it is almost the case that the release button operation is intended to start the photographing operation, the line-of-sight detection is not performed when the first switch means is closed this time, and the result of the line-of-sight detection performed immediately before is displayed. The focus detection position is determined by using the focus detection position, and the focus adjustment is performed based on the focus detection information obtained here.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on illustrated embodiments.

FIG. 1 is a configuration diagram showing a main part of a single lens reflex camera according to a first embodiment of the present invention, FIG. 2 is a diagram showing an upper surface and a back surface of the single lens reflex camera of FIG. 1, and FIG. 3 is a diagram showing the inside of a viewfinder of the camera of FIG.

1 to 3, reference numeral 1 denotes a taking lens, which is illustrated as two lenses 1a and 1b for convenience of illustration.
Actually, it is composed of many lenses.

Reference numeral 2 is a main mirror, which is obliquely installed in the photographing optical path or retreated according to the observation state and the photographing state. A sub-mirror 3 reflects a light beam transmitted through the main mirror 2 toward the lower side of the camera body. Reference numeral 4 is a shutter, and 5 is a photosensitive member, which comprises a solid-state image pickup device such as a silver salt film or a CCD or an image pickup tube such as a vidicon.

Reference numeral 6 denotes a focus detection device, which is a fold lens 6a and reflection mirrors 6b and 6 arranged near the image plane.
c, a secondary imaging lens 6d, a diaphragm 6e, and a line sensor 6f such as a CCD including a plurality of photoelectric conversion elements.

The focus detection device 6 in this embodiment employs a well-known phase difference method, and as shown in FIG. 3, distances are measured in a plurality of regions (5 places) within the observation screen (in the viewfinder field). As a point, the focus detection point is configured to be capable of focus detection.

Reference numeral 7 is a focusing plate arranged on the planned image forming surface of the taking lens 1, 8 is a pentaprism for changing the optical path of the finder, and 9 and 10 are image forming lenses and photometry for measuring the brightness of the subject in the observation screen. In the sensor, the image forming lens conjugately connects the focusing plate 7 and the photometric sensor via the reflected light path in the penta roof prism 8.

Reference numeral 11 denotes an eyepiece lens arranged behind the exit surface of the penta roof prism 8, which has a light splitter 11a and is used for observing the focusing plate 7 by the eye 15 of the photographer. The light splitter 11a is formed of, for example, a dichroic mirror that transmits visible light and reflects infrared light. 1
Reference numeral 2 is a light receiving lens, and 14 is an image sensor in which a photoelectric element array such as CCD is two-dimensionally arranged so as to be conjugated with the vicinity of the pupil of the photographer's eye 15 at a predetermined position with respect to the light receiving lens 12. The image sensor 14 and the light receiving lens 12 constitute one element of the light receiving means.

Reference numerals 13 (13a to 13d) each denote an infrared light emitting diode which is an illuminating light source (projecting means) of the photographer's eye 15, and is provided around the eyepiece lens 11 as shown in FIG. 2B. It is arranged.

Reference numeral 21 is a high-intensity superimposing LED that can be visually recognized even in a bright subject. The light emitted from the superimposing LED 21 is reflected by the projection prism 22 and the main mirror 2 to focus the focus plate 7. Is bent in the vertical direction by the micro prism array 7a provided in the display section of
It reaches the photographer's eye 15 through the pentaprism 8 and the eyepiece lens 11. Therefore, the minute prism array 7a is formed in a frame shape at a position corresponding to the focus detection area of the focusing plate 7, and the five superimposing LEDs 21 (each of which are LED-L1, LED-L2, LE) corresponding thereto are formed.
D-C, LED-R1, LED-R2).

As a result, as can be seen from the viewfinder field view shown in FIG. 3, the distance measuring point marks 200, 2 respectively.
01, 202, 203, and 204 illuminate in the finder field to display the focus detection area (distance measuring point) (hereinafter,
This is called the superimpose display).

Reference numeral 23 is a field mask for forming a finder field area, and 24 is an LCD in the finder for displaying photographing information outside the field of view of the finder, which is an illumination LED (F-LE).
D) Illuminated by 25, LCD 24 in the viewfinder
The light transmitted through is guided by the triangular prism 26 into the finder and displayed outside the finder field of view of FIG. 3, and the photographer observes the photographing information. 27 is a posture detection means, which is a posture detection sensor for detecting the posture of the camera.

Reference numeral 31 denotes an aperture provided in the taking lens 1, 32
Is a diaphragm driving device including a diaphragm driving circuit 111 described later, 3
Reference numeral 3 is a lens driving motor, and 34 is a lens driving member including a driving gear and the like. A photocoupler 35 detects the rotation of the pulse plate 36 interlocked with the lens driving member 34 and transmits it to the lens focus adjustment circuit 110. The focus adjustment circuit 110 indicates this information and the lens drive amount from the camera side. The lens driving motor is driven by a predetermined amount based on the information to move the taking lens 1 to the in-focus position.
A mount contact 37 serves as an interface between a known camera and lens.

In FIG. 2, reference numeral 41 is a release button, 42 is a monitor LCD as an external monitor display device, and a fixed segment display portion 42a for displaying a predetermined pattern and a 7-segment display portion 42b for displaying variable numerical values. And consists of. Reference numeral 43 is an AE lock button for holding a photometric value, and 44 is a mode dial for selecting a shooting mode or the like. Reference numeral 45 is an electronic dial. The other operating members are omitted because they are not particularly necessary for understanding the present invention.

FIG. 4 is a block diagram showing a main part of an electric circuit built in the single-lens reflex camera having the above-mentioned structure.

FIG. 4 is a block diagram showing the configuration of electrical main parts of a camera to which the first embodiment of the present invention is applied. First, the structure of each part will be described. The same parts as those in FIG. 1 are designated by the same reference numerals.

In FIG. 4, PRS is a camera control circuit, for example, a CPU (central processing unit), RA
This is a one-chip microcomputer (hereinafter, referred to as a microcomputer) in which an M, a ROM, an in-finder port, and the like are arranged.

The microcomputer PRS100 includes a line-of-sight detection path 101, a photometric circuit 102, an automatic focus detection circuit 103,
A signal input circuit 104, an LCD drive circuit 105, an LED drive circuit 106, an IRED drive circuit 107, a shutter control circuit 108, and a motor control circuit 109 are connected, and a camera sequence program and control stored in a ROM and an EEPROM. The series of operations of the camera is performed by controlling the above-mentioned circuits according to the parameters.

Signals are transmitted to the focus adjusting circuit 110 and the diaphragm driving circuit 111 arranged in the photographing lens 1 through the mount contact 37 shown in FIG.

EEPR attached to the microcomputer PRS100
OM (electrically erasable programmable ROM) 100a
Includes line-of-sight correction data (hereinafter,
It is stored as a series of control parameters for the camera, including calibration data) and adjustment values for exposure control and focus adjustment.

The line-of-sight detection circuit 101 A / D outputs the output of the eyeball image from the image sensor 14 (CCD-EYE).
After conversion, this image information is transmitted to the microcomputer PRS100. As will be described later, the microcomputer PRS100 extracts each feature point of the eyeball image necessary for sight line detection according to a predetermined algorithm, and further calculates the photographer's sight line from the position of each feature point. The microcomputer PRS100, the visual axis detection circuit 101, and the image sensor 14 constitute one element of the visual axis detection device.

The photometric circuit 102 amplifies the output from the photometric sensor 10, performs logarithmic compression and A / D conversion, and outputs it to the microcomputer PRS100 as brightness information of each sensor. The photometric sensor 10 includes an SPC-L for photometry of a left area 210 including the left focus points 200 and 201 in the finder screen shown in FIG. 3 and a central area 21 including a central focus area 202.
SPC-C for metering 1 and distance measuring points 203, 20 on the right side
It is composed of four photodiodes, that is, an SPC-R that photometers the right side region 212 including 4 and an SPC-A that photometers these peripheral regions 213.

The line sensor 6f includes five sets of line sensors CCD-L2, CCD-L1, CCD-C and CC corresponding to the five distance measuring points 200 to 204 on the screen as described above.
This is a known CCD line sensor composed of D-R1 and CCD-R2. The automatic focus detection circuit 103 A / D converts the voltage obtained from these line sensors 6f and sends it to the microcomputer PRS100.

SW1 is a switch for starting photometry, AF (autofocus), line-of-sight detecting operation, etc., that is, for starting the shooting preparation operation, SW2 is a release switch for starting the shooting operation, and SW-ANG is Attitude detection switch detected by the line-of-sight detection sensor 27, SW-AEL is an AE lock switch that is turned on by pressing the AE lock button 43, and SW-DIAL1 and SW-DIAL2 are dials provided in the electronic dial already described. It is a switch.

The switch SW1 is a switch which is turned on by pressing the release button 41 in the first step (first stroke), and the release switch SW2 is subsequently pressed by the second step of pressing the release button 41 (second stroke). This is a switch that turns on. These switches SW1, S
One of both W2 is grounded and the other is connected in parallel to the terminal of the microcomputer PRS100. Microcomputer PRS to which these switches SW1 and SW2 are connected
The terminal 100 is connected to the positive terminal of the battery by a pull-up resistor (not shown).

The status signals of the various switches described above are input to the signal input circuit 104.
The switch state is detected without being affected by chattering that occurs when the OFF state is switched.

Dial switches SW-DIAL1 and SW
-DIAL2 is input to the up / down counter built in the signal input circuit 104 and counts the rotation click amount of the electronic dial 45. SW-M1 to M4 are also dial switches provided in the mode dial 44 already described. The signals of these switches are input to the signal input circuit 104 and transmitted to the microcomputer PRS100 via the data bus.

When the microcomputer PRS100 learns that the switch SW1 is turned on, it pulls down the terminal connected through the resistor to turn on the transistor PTR112 to LOW level. Then, when a predetermined time has elapsed since the last time the switch SW1 was turned on by the built-in timer, power is supplied to the electric elements that have been powered off, and a series of controls such as photometry and focus detection are started. , Resets the built-in timer that controls power supply and restarts clocking. Then, when a predetermined time has elapsed according to the time measured by the built-in timer, the transistor PTR112 is turned off to stop the power supply to the electric element. Further, when the switch SW2 is turned on, the release operation including exposure control and subsequent film winding is performed by using this as a trigger.

The power supply circuit 112 is a constant voltage power supply, to which a battery output VBAT (not shown) is input, and its output is connected to the power supply terminal of the microcomputer PRS100 and the signal input circuit 104. Further, under the control of the microcomputer PRS100, after being output to VCC via the transistor PTR113, it is supplied to each electric element. In the figure, VCC is connected to all electric elements, but its description is omitted.

Reference numeral 105 denotes a known LCD drive circuit for driving the liquid crystal display element LCD to display, and the microcomputer PR
In accordance with the signal from S100, the display of the aperture value, shutter speed, set shooting mode, etc. is simultaneously displayed on both the monitor LCD 42 and the in-finder LCD 24.

The LED drive circuit 106 is an LED for illumination.
(F-LED) 22 and LED 21 for superimpose
Is turned on and off. The IRED drive circuit 107 selectively lights the infrared light emitting diodes (IRED1 to 6) 13a to 13d according to the situation.

The shutter control circuit 108 controls the magnet MG-1 which runs the front curtain and the magnet MG-2 which runs the rear curtain when energized to expose the photosensitive member with a predetermined amount of light. The motor control circuit 109 controls a motor M1 that winds and rewinds the film and a motor M2 that charges the main mirror 2 and the shutter 4.
These shutter control circuit 108 and motor control circuit 109
The series of camera release sequences operates.

FIG. 5 is a diagram for explaining the principle of the visual axis detection method. 6A is a schematic diagram of an eyeball image projected on the surface of the image sensor 14, and FIG. 6B is the same diagram as FIG.
The image signal output of the image sensor 14 on a straight line passing through the ends a and b of the iris shown in FIG.

In FIG. 6 (A), 17 is the iris portion of the eyeball, 19 is the pupil, and e and d are the corneal reflection images of the eyeball illumination light source.

In the figure, 13a and 13b are light sources such as light emitting diodes that emit infrared light insensitive to the observer, and each light source is substantially symmetrical with respect to the optical axis of the light receiving lens 12 in the x direction. It is placed and divergently illuminates the eyes of the observer. A part of the illumination light reflected by the eyeball is focused on the image sensor 14 by the light receiving lens 11.

Next, the visual axis detection method will be described with reference to FIGS. 5 and 6A and 6B.

The infrared light emitted from the light source 13b illuminates the cornea 16 of the eyeball 15 of the observer. At this time, the cornea 16
The corneal reflection image d (virtual image) formed by a part of the infrared light reflected by the surface of the light is condensed by the light receiving lens 11 and imaged at the position d ′ on the image sensor 14. Similarly, light source 5
The infrared light emitted from a illuminates the cornea 16 of the eyeball. At this time, the corneal reflection image e formed by a part of the infrared light reflected on the surface of the cornea 16 is condensed by the light receiving lens 11 and imaged at the position e ′ on the image sensor 14.
Further, the light flux from the ends a and b of the iris 17 is received by the light receiving lens 1
The images of the end portions a and b are formed at the positions a ′ and b ′ on the image sensor 14 via 1.

When the rotation angle θ of the optical axis of the eyeball 15 with respect to the optical axis of the light receiving lens 11 is small, and the x coordinates of the ends a and b of the iris 17 are xa and xb, the coordinate xc of the center position c of the pupil 19 is represented. Is expressed as xc≈ (xa + xb) / 2.

Since the x-coordinate of the midpoint of the corneal reflection images d and e and the x-coordinate xo of the center of curvature O of the cornea 16 substantially coincide with each other, the x-coordinates of the corneal reflection image generation positions d and e are xd, x
e, the standard distance between the center of curvature O of the cornea 16 and the center C of the pupil 19 is / OC, and the coefficient considering the individual difference for the distance / OC is A, the rotation angle θ of the optical axis of the eyeball 15
Substantially satisfies the relational expression of (A * / OC) * SIN θ≈xc (xd + xe) / 2 (1). Therefore, as shown in FIG. 6A, by detecting the position of each feature point of the eyeball 15 projected onto the image sensor 14 (corneal reflection images d and e and iris edges a and b). The rotation angle θ of the optical axis of the eyeball 15 can be obtained. At this time, the expression (1) is rewritten as β * (A * / OC) * SINθ≈ (xa ′ + xb ′) / 2− (xd ′ + xe ′) / 2 (2). However, β is a magnification determined by the position of the eyeball with respect to the light receiving lens 11, and is substantially obtained as a function of the interval | xd′−xe ′ | of corneal reflection images.

The rotation angle θ of the optical axis of the eyeball 15 can be rewritten as θ≈ARCSIN {(xc′−xf ′) / β / (A * / OC} (3), where xc′≈ (xa ′ + xb ′) ) / 2 xf'≈ (xd '+ xe') / 2.

Since the optical axis of the eyeball of the observer and the visual axis do not coincide with each other, when the horizontal rotation angle θ of the optical axis of the eyeball of the observer is calculated, the optical axis of the eyeball and the visual axis of the eyeball are calculated. By correcting the angle difference α, the horizontal line of sight θx of the observer can be obtained. Letting B be a coefficient that takes into account individual differences with respect to the correction angle α between the optical axis of the eyeball and the visual axis, the horizontal line of sight θx of the observer is calculated as θx = θ ± (B * α) (4) To be Here, if the angle of rotation to the right with respect to the observer is positive, the sign ± is selected as + when the eye of the observer looking into the observation device is the left eye, and when the eye of the observer is the right eye. Further, in the figure, an example in which the observer's eyeball rotates in the z-x plane (for example, horizontal plane) is shown, but when the observer's eyeball rotates in the y-z plane (for example, vertical plane) Can be similarly detected. However, since the vertical component of the line of sight of the observer matches the vertical component θ ′ of the optical axis of the eyeball, the vertical line of sight θy is θy = θ ′.

Further, in the single-lens reflex camera, the position (xn, yn) on the focus plate viewed by the observer from the line-of-sight data θx, θy is xn≈m * θx≈m * [ARCSIN {(xc'-xf ′) / Β / (A * / OC)} ± (B * α)] (5) yn≈m * θy However, m is a constant determined by the finder optical system of the camera.

Here, the coefficient for correcting the individual difference of the line of sight, that is, the individual difference correction coefficient is A, and the value of B fixes the photographer's eye on the index arranged at a predetermined position in the viewfinder of the camera. It is obtained by matching the position of the index with the fixation point position calculated according to the equation (5).

The calculation for obtaining the line-of-sight and gazing point of the photographer in the present embodiment is executed by executing the program of the microcomputer of the line-of-sight calculation processing device based on the above equations.

The position of the line of sight of the photographer looking through the viewfinder of the camera on the focus plate is correctly calculated, and the line-of-sight information is used for focus adjustment of the photographing lens, exposure control, or the like.

Next, the operation will be described with reference to the flow charts shown in FIGS.

First, FIG. 7 shows the main operation of the camera.
This will be described with reference to the flowchart of.

When the mode dial 44 is rotated to set the camera to the predetermined photographing mode from the inoperative state, the signal input circuit 104 detects the rotation operation of the mode dial 44 and communicates with the microcomputer PRS100 (step # 001).

In step # 002, the signal input circuit 10
In response to the signal from 4, the microcomputer PRS100 initializes flags, registers, ports, etc., reads data from the built-in ROM as needed, stores the data in a predetermined position in the memory, and monitors it. LCD4
2, a series of initialization operations such as transmitting data such as the shooting mode of the camera to the LCD drive circuit 105 is performed. At this time, appropriate values are respectively assigned to the registers in the microcomputer PRS100, and SW0F,
Flags in the microcomputer PRS100 such as W1F, PTRF, AFF, and TIMERF are cleared to "0", and each output port is also initialized.

When the initialization operation is completed, the release button 41
It is checked whether or not the switch SW1 which is operated by pressing in the first step is ON (step # 003). If the switch SW1 is on, then the flag PTRF is checked (step # 007). This flag PTRF indicates the state of the port of the microcomputer PRS100 connected to the base of the transistor PTR113 via a resistor. When it is "0", the transistor PTR113 turns off, and when it is "1", the transistor PTR11.
3 turns on.

When the mode dial 44 is rotated to set the camera from the inoperative state to the predetermined photographing state, the flag PTRF is still "0". Therefore, the microcomputer P connected to the above-mentioned transistor PTR113
The port of RS100 is pulled down to LOW level to turn on the transistor PTR113, and the flag PT
"1" is set to RF (step # 008). When the transistor PTR113 is turned on, power is supplied from the power supply circuit 112 to VCC, and power is supplied to electric elements such as the photometry circuit 102 and the automatic focus detection circuit 103 that are supplied only when necessary.

The focus adjustment circuit 110 and the diaphragm drive circuit of the photographing lens 1 mounted via the mount 37 store the data required for a series of data processing such as photometric calculation and focus adjustment control with each electric element supplied with power. It communicates with 111 and stores it in a predetermined location of the memory (step # 009).

Then, the timer built in the microcomputer PRS100 which determines the duration for which the transistor PTR113 is kept on is set and operated, and "1" is set in the flag TIMEF indicating that the built-in timer is in the time counting operation ( Step # 010). The flag TIMEF is set to "1" while the timer is operating, and is set to "0" before the time is completed or before the time is started.

Here, the time counted once by the timer built in the above-mentioned microcomputer PRS100 is the same as that in step # 003.
To step # 030 or step # 00
This time is longer than the time required to perform the processing operations from Step 3 to Step # 045 and return to Step # 003 again.

Subsequently, in the "setting" subroutine, information is input by operating each switch and display based on the input information is performed (step # 011).

Then, in step # 012, the output from the photometric circuit is converted into a digital value by the A / D converter incorporated in the microcomputer PRS100 and taken in to obtain photometric data, and the information from the above-mentioned taking lens is used. hand,
At that time, a series of photometric processing such as calculation of optimum exposure control information is performed by calculation according to the shooting mode of the camera set. Then, the microcomputer PRS100 outputs the obtained photometric processing result to the LCD drive circuit 105 and displays it on the in-finder LCD 24 and the monitor LCD 42.

At step # 015, line-of-sight detection is executed. A detailed description of the gaze detection will be given later.

At this time, the LED drive circuit 106 is the L for illumination.
The ED (F-LED) 25 is turned on, and the LCD drive circuit 1
Reference numeral 05 indicates that the line-of-sight input mark 78 of the LCD 24 in the finder is turned on so that the photographer can confirm on the outside 207 of the finder screen that the camera is performing line-of-sight detection.

In step # 016, the line-of-sight detection circuit 10
The line of sight detected in 1 is converted into the gazing point coordinates on the focus plate 7, the microcomputer PRS100 selects a distance measuring point close to the obtained gazing point coordinates, and sends a signal to the LED drive circuit 106 to superimpose. The distance measuring point mark is made to blink by using the pause LED 21.

As described above, the fact that the distance measuring point is selected by the line-of-sight information is indicated by blinking the distance measuring mark in the viewfinder to notify the photographer, so that the photographer can select as desired. You can check whether or not.

In step # 019, the photographer sees that the distance measuring point selected by the photographer's line of sight is displayed and further sees whether or not the switch SW1 is continuously pressed. That is, if the selected focus detection point does not match the intention, the photographer recognizes that it is incorrect and releases the release button 41 to turn off the switch SW1. If they match, the switch SW1 is continuously operated. Because it keeps pushing. If the switch SW1 is off, the process proceeds to step # 041.

When the photographer sees that the distance measuring point selected by the line of sight is displayed and continues to turn on the switch SW1, the process proceeds to step # 021, and in this step # 021, a series of AF is performed. Perform processing and AF operation.
That is, the automatic focus detection circuit 103 uses the detected line-of-sight information to detect the focus of one or more focus detection points.
If the focus adjustment state of the selected focus detection area is not in focus, the microcomputer PRS100 causes the lens focus adjustment circuit 11
A signal is sent to 0 to drive the taking lens 1 by a predetermined amount. After driving the lens, the automatic focus detection circuit 103 performs focus detection again, and if the subject is not in focus, drives the taking lens 1 again to perform focus adjustment.

In the next step # 022, the taking lens 1
Is in focus, that is, it is determined whether or not focus adjustment was possible.
When the photographic lens 1 is focused and focused at a predetermined distance measuring point, the microcomputer PRS100 sends a signal to the LCD drive circuit 105 to turn on the focus mark 79 of the LCD 24 in the finder and the LED drive circuit 10
A signal is also sent to 6 to display a focus on the focus detection point 201 which is in focus. At this time, the blinking display of the focus detection point selected by the line of sight is turned off, but the focus detection displayed focus point and the focus detection point selected by the line of sight are often coincident with each other. In order to let the photographer recognize that this has been done, the focusing distance measuring point is set to a lighting state.

If it is determined in step # 022 that the taking lens 1 is out of focus, that is, if the focus cannot be adjusted, the process proceeds to step # 023 and the microcomputer PRS10 is operated.
0 sends a signal to the LCD drive circuit 105 to blink the focus mark 79 of the in-viewfinder LCD 24 to warn the photographer that the focus adjustment is NG (disabled) and the focus cannot be achieved.

Further, in step # 024, it is detected whether or not the switch SW1 is off, and the switch SW1 is detected.
1 is on, that is, the photographer releases the release button 41.
While pressing, the focus adjustment NG display is continued. Then, the photographer releases the release button 41 and the switch SW
When 1 is turned off, the process proceeds to step # 041.

In step # 025, the photographer sees the focused focus detection point displayed in the viewfinder, recognizes that the focus detection point is not correct, and releases the release button 41 to release the switch SW1. When turned off, the process proceeds to step # 041.

Further, when the switch SW1 is still on, in step # 026, the result obtained in the "photometry" of step # 012 and the above step # 0
The exposure control value is determined from the focus state of each focus detection point, the focus of which is adjusted in 021.

At the following step # 030, the switch SW
2 is turned on. If the switch SW2 is turned on, the process proceeds to step # 040 to perform a release process.

In the release processing of step # 040, first, the motor M2 is energized via the motor control circuit 109 to raise the main mirror 2 and the diaphragm 31 is narrowed down, and then the magnet MG1 is energized to energize the shutter 4. Open the first curtain. The aperture value of the aperture 31 and the shutter speed of the shutter 4 are determined from the exposure value detected by the photometric circuit 102 and the sensitivity of the film 5. After a lapse of a predetermined shutter time, the magnet MG2 is energized via the shutter control circuit 108 to close the rear curtain of the shutter 4. When the exposure of the film 5 is completed, the motor M2 is energized again to perform mirror down and shutter charging, and
Power is also supplied to 1 to feed the film frame, and a series of release processing operations is completed.

In step # 030, the switch S
When W2 is off, as described above, step # 00.
Then, the process goes to 3 to check again whether the switch SW1 is on. Then, in step # 003, the switch SW is turned on again.
It is checked whether or not 1 is on. If it is off, the process proceeds to step # 041. Steps # 019 and # 02
Even when the switch SW1 is OFF in 4 and # 025, the process proceeds to step # 041 as described above. Then, in this step # 041, the flag SW1F is set to "0".

In the following step # 042, the flag TIM is set.
Check the EF. If the flag TIMEF is not "1", it means that the built-in timer has already finished counting the predetermined time, and upon completion of the timing, the microcomputer PRS100 turns off the transistor PTR113. At this time, the camera is in a power supply stop state in which power supply by VCC is stopped so that unnecessary power is not consumed, and whether or not the switch SW1 is turned on again in order to determine whether or not the camera is in the shooting state. Return to the operation for checking whether or not, that is, step # 003.
Return to

In step # 043, the flag TIME is set.
When F is “1”, in the next step # 043,
Check whether the built-in timer has finished timing. If the built-in timer has not finished timing, it means that the camera is in the shooting state, and the process moves to step # 010 again. If the built-in timer has finished measuring time, as described above, processing is performed to put the camera into a shooting preparation state so as not to consume extra power.

That is, first, in step # 044, the flag TIMEF is set to "0" to indicate that the built-in timer has been timed, and then in step # 045, the transistor PTR113 is turned off. Furthermore, the flag PT
RF is set to "0" to perform a process indicating that the transistor PTR113 is off, and the camera is ready for shooting.

Then, the process returns to step # 003, and the switch S is pressed to determine whether or not the camera is set in the photographing state.
The procedure returns to the operation for checking whether W1 is on.

As described above, the main operation of the camera is to detect the line of sight (step # 015) and measure the distance when the switch SW1 is turned on while the power supply transistor PTR113 is off and the power supply is stopped. Once the power supply is started once the selection (step # 016), AF (step # 021) and processing proceed, the timer allows the photographer to release before the power supply is stopped again after a predetermined time elapses. Even if the switch SW1 is off by releasing the finger from the button 41, the setting (step # 011),
Photometry (step # 012), line-of-sight detection (step # 01
5) and distance measuring point selection (step # 016) are repeated in this order.

FIG. 8 is a flow chart showing the line-of-sight detection operation, and the line-of-sight detection operation will be described in detail below using this.

In the flow chart shown in FIG. 8, when the visual axis detection circuit 101 receives a signal from the microcomputer PRS100, the visual axis detection circuit 101 executes visual axis detection. This corresponds to the operation in step # 015 in FIG.

When line-of-sight detection is started, data initialization is executed in step # 051 through step # 050 in FIG.

The variable EYEMIN is a variable for storing the minimum luminance value in the photoelectric conversion signal of the eyeball reflection image, and assuming that the resolution of the A / D converter built in the microcomputer PRS100 is 8 bits, As the signal is read, the lowest value is sequentially compared and updated. As the initial value, “255” indicating the maximum value of 8 bits is stored.

The variable EDGCNT is a variable for counting the number of extracted edges of the boundary between the iris and the pupil.

Variables IP1, IP2, JP1, JP2
Is a corneal reflection image of the light emitting diodes 5a and 5b (hereinafter, P
Image (Purkinje image)) is a variable that represents the position of
Horizontal direction (X axis) range IP1 to IP2, horizontal direction (Y axis)
There are two P images in the area of the eyeball reflection image surrounded by the ranges JP1 and JP2.

The number of pixels of the image sensor (also referred to as an area sensor) 14 is 150 pixels in the horizontal direction and 10 pixels in the vertical direction.
Assuming a size of 0 pixels, variables IP1, IP2,
JP1 and JP2 are at the exact middle position (75,5
0) is stored as an initial value.

After data initialization, the next step # 05
Move to 2.

At step # 052, the light emitting diodes 5a and 5b for P image and the light emitting diodes 5c and 5c for eyeball illumination are
Turn on 5d. Then, in the next step # 053,
The accumulation operation of the area sensor 14 is started.

Since the control of the area sensor 14 is not directly related to the present invention, detailed description will be omitted.

In step # 054, the end of storage of the area sensor 14 is awaited. When a predetermined charge is accumulated according to the incident light and the accumulation is completed, in the next step # 055,
Turn off the light emitting diode.

From the next step # 058 onward, the reading of the photoelectric conversion signal of the area sensor 14 is started.

In step # 058, so-called "loop processing" is executed in which the processing within the frame is executed while counting up the loop variable J from "0" to "99".

In the loop processing in step # 058, first in step # 059, the photoelectric conversion signal of one line in the lateral direction (X axis) of the area sensor 14 is read.
Reading one line is in a subroutine format,
This subroutine "reading one line" is shown in FIG.
This will be described with reference to the flowchart of.

When the subroutine "read one line" is called, the next step # 101 is executed through step # 100) in FIG.

Step # 101 and steps within the frame #
Reference numeral 102 represents the same loop processing as in step # 058 described above, and in step # 101, the above-mentioned step # 0.
The same loop processing as 58 is shown. Further, in step # 101, the variable K is incremented from “0” to “3”, and in step # 102, the variable I is incremented.
Counting up from "0" to "149",
The processing within each frame is executed. Therefore, step # 101 and step # 102 represent so-called “nested” loop processing of variable K and variable I.

In step # 103 in the loop processing of step # 102, the re-storing work of the array variable IM (i, k) is performed.

In this embodiment, the microcomputer PRS100 is used.
However, in general, the storage capacity of the built-in RAM of the microcomputer is not large enough to store all the pixel information of the area sensor at once.

Therefore, in the present embodiment, the image signals output from the area sensor 17 are sequentially read out, but only the latest image signals corresponding to 5 lines in the horizontal direction (X axis) are stored in the built-in RAM of the microcomputer PRS100. It is stored and the process for detecting the line of sight is executed every time one line is read.

The contents executed in the double loop processing from step # 101 to step # 103 is that the image signal data for the past five lines stored is updated in order to read a new image signal for one line. It is a task to do. That is,
Of the array variables IM (i, k), IM (i, 0) [i =
0-149] is the oldest, and IM (i, 4) [i
= 0 to 149] represents the most recent one-line image data, and the data is updated as follows to generate a new one-line image signal IM (i, 4) [i = 0 to 149]. Prepare to store in.

IM (i, 0) ← IM (i, 1) IM (i, 1) ← IM (i, 2) IM (i, 2) ← IM (i, 3) IM (i, 3) ← IM (I, 4) [i = 0 to 149] Now, when the loop process for updating the data in steps # 101 to # 103 ends, the next step # 1
The loop processing of 04 is executed.

In the loop processing of step # 104, the image signal of one line (designated pixel) in the horizontal direction (X axis) of the area sensor 17 is sequentially A / D converted and R
It is stored in AM and the minimum value of the image signal is detected.

At the first step # 105 in the loop of step # 104, the built-in A / D of the microcomputer PRS100 is
Digital value ADC obtained by A / D converting the image signal from the converter
Is taken out, the value is temporarily converted, and the variable EYEDT
To be stored. Then, in the next step # 106, the value of the variable EYEDT is stored in the array variable IM (i, 4).
The variable i is counted up from the variable “0” to “149” in the outer loop processing step # 104.

Step # 107 and step # 108 are
This is a process of detecting the minimum value of the image signal. Variable EYEIN
Is a variable that holds the minimum value of the image signal, and step # 1
07), from the variable EYEMIN to the variable EYEDT
Is smaller, the process branches to step # 108) and the variable EYEMIN is updated with the value of this small variable EYEDT.

When the loop processing of steps # 104 to # 108 is completed and the storage of the image signal for one new line and the detection of the minimum value are completed, the subroutine "read one line" is executed in the next step # 109. To return.

Returning to the flowchart of FIG. 8, when the subroutine "reading one line" of step # 059 is completed, the process proceeds to the next step # 060, and the loop variable J of the outer loop processing step # 058 is "5". Check whether the above.

The loop variable J represents the pixel line of the area sensor 17 in the vertical direction (Y axis). Step # 060
If the loop variable J is "5" or more, step #
Branch to 061. This is because when the number of lines of the read image signal becomes 5 or more, the vertical direction (Y
This is because it becomes possible to process (axis).

In step # 061, which is a branch destination, a subroutine "detection of P image" is executed.

The subroutine "detection of P image" is a process for detecting the position of the above-mentioned corneal reflection image (P image), and is executed every time one line of the area sensor 17 is read in the lateral direction (X axis). To do. The flowchart is shown in FIG. 10, which will be described below.

When the subroutine "P image detection" is called, the loop processing of step # 201 is executed after step # 200. In the loop processing, the position of the P image in the image data (stored in the array variable IM (i, k)) is searched,
If found, its position on the area sensor 17 is stored. In this embodiment, since two P images are generated, the number of pieces of position information to be stored is also two.

In the first step # 202 in the loop,
It is determined whether the image data at the predetermined position satisfies the condition for the P image. The conditions are as follows.

"P image condition" of step # 202) IM (1,2)> C2 and IM (1,1)> C2 and IM (1,3)> C2 and IM (I-1,2)> C2 IM (I + 1,2)> C2 However, C1 and C2 are square value constants, and have a relationship of C1 ≧ C2. For example, C1 = 230 and C2 = 200. A variable I is a loop variable for loop processing and represents the position of the area sensor 17 in the horizontal direction (X axis).

With the above conditions, paying attention to the fact that the P image is like a spot image as shown in FIGS. 6 (A) and 6 (B), the horizontal / vertical directions (X / Y axes) in both directions. As defined in. When this condition is satisfied, it is considered that the P image exists at the position (1,2).

As described above, the array variable IM (i, k) is updated each time the area sensor reads one line in the horizontal direction (X axis), and the vertical direction (Y axis) position J line is IM.
It is stored in (i, 4) [i = 0 to 149]. Therefore, the address (1, 2) for the variable IM is the position (I, J-2) on the area sensor 17.

At step # 202, if there is image data satisfying the P image condition, and if the process does not branch to step # 203 and thereafter, the outer loop variable I is incremented.

Step # 203 and subsequent steps are the processes for determining the existence range of the two P images (range in the X-axis direction [IP1 to IP2], range in the Y-axis direction [JP1 to JP2]).

First, in step # 203, a variable I and a variable IP representing the lateral (X-axis) position of the area sensor 17 are displayed.
1 is compared, and if I <IP1, the process branches to step # 204. That is, if the position of the variable I is on the left side of the position of the P image position IP1 on the left side in the horizontal direction in the existence range of the P image, the variable IP1 is rewritten.

At step # 204, the value of the variable I is stored in the variable IP1, and the vertical position (J-2) at that time is stored in the variable JP1. In subsequent steps # 205 and # 206, it is determined whether or not the P image position IP2 on the right side in the horizontal direction of the P image existing range and JP2 representing the vertical position thereof are updated.

As described above, in the loop process of step # 201, the position I in the horizontal direction (X axis) is changed from "0" to "1".
When the processing for each line is completed up to 49 ", the process proceeds to the next step # 207.

At step # 207, the variables XP1, XP2, YP1 and YP2 to be referred to in the subsequent processing are calculated according to the equations in the figure. The meanings of these variables will be described in detail in the explanation of the least squares estimation subroutine for the circle in FIG. 14. Briefly speaking, when detecting the center of the pupil,
This is used to eliminate false pupil edge information generated around the P image position.

When the processing in step # 207 is completed, the subroutine "P image detection" is returned in step # 208.

Returning again to the flowchart of FIG.

When the subroutine "P image detection" in step # 061 is completed, the subroutine "pupil edge detection" is executed in step # 062. The "pupil edge detection" is a subroutine for detecting the position of the pupil edge (border between the iris and the pupil) in the eyeball reflection image, and its flowchart is shown in FIG. 11, which will be described below.

When the subroutine "pupil edge detection" is called, the process proceeds to step # 300 and then to the next step #.
The loop process 301 is executed. Step # 301 is
As in step # 201 of FIG. 10, the area sensor 17
Is a loop process in which a variable I representing the position in the horizontal direction (X axis) is used as a loop variable.

In the loop processing of step # 301, it is searched whether or not the image data has a feature representing the edge of the pupil, and if there is, the position information is stored. The pupil edge position information is stored in the array variable EDGDTP (m, n). The data format of the array variable EDGDT (m, n) is set as follows.

EDGDT (m, 1) ... Luminance of the mth edge point EDGDT (m, 2) .... X-axis coordinate of the mth edge point EDGDT (m, 3). However, m is the order of the edge points found during the sequential processing of pupil edge detection. Therefore, if m edges are detected, the capacity of the array variable EDGDT requires about [M × 3] bytes. In the flowchart, the number of detected edges is counted by the variable EDGCNT.

Now, the first step # 302 in the loop
Then, it is determined whether or not there is an edge point detected in the past in the vicinity of the image data IM (I, 2). The more detailed explanation is as follows.

The loop variable I of the outer loop processing represents the lateral (X-axis) position of the area sensor 17, and the address (I, 2) for the array variable IM (i, k) that stores the image data. Is the point (pixel coordinate) that is about to be detected whether or not it is the pupil edge. It will be checked from the array variable EDGDT (m, n) that stores edge position information whether or not each point adjacent to the point (I, 2) has been determined to be a pupil edge in the course of past sequential processing. It is what

The determination condition of step # 302 will be described in detail as follows.

"Judgment condition" in step # 302 Becomes {EDGDT (m, 2), EDGDT (m, 3)}
Exists. However, m = 0 to (EDGCNT-1).

The coordinates currently being tested are:
Since it is {(I), (J-2)}, the above-mentioned coordinates represent the positions of the left side, the upper left side, the upper side, and the upper right side in order with respect to the current coordinates.

Further, EDGDT (m, 2), EDGDT
(M, 3) is the X-axis coordinate of the m-th edge point, Y
Since the axis coordinates are represented, the above condition is, after all, determined whether or not there is an edge point at the position of the left side, the upper left side, the upper side, and the upper right side of the current coordinate.

At step # 302, the coordinates (I, J
If it is determined that there is an edge point in the vicinity of -2),
Go to step # 304, otherwise step # 3
The process branches to 03, and the pupil edge is determined using different conditions.

The case where there is no edge point in the vicinity will be described first.

At step # 303, it is determined whether or not the image data of the coordinate (I, J-2) currently to be verified satisfies the condition of the pupil edge (the judgment condition at step # 303 is referred to as "edge condition 1"). Is being determined. Note that the image data at coordinates (I, J-2) is stored in the array variable IM (I, 2).

The judgment conditions are as follows.

"Edge condition 1" in step # 303 1. {IM (I-1,2) -IM (1,2)}> C3 and {IM (I-2,2) -IM (I-1,2)} <C3 and IM (I, 2) <a 2. {IM (I + 1,2) -IM (1,2)}> C3 and {IM (I + 2,2) -IM (I + 1,2)}> C3 and IM (I, 2) <a3. 3. {IM (I, 1) -IM (1,2)}> C3 and {IM (I, 0) -IM (I, 1)}> C3 and IM (I, 2) <a4. {IM (I, 3) -IM (1,2)}> C3 and {IM (I, 4) -IM (I, 3)}> C3 and IM (I, 2) <a Above 1. ~ 4. If is satisfied, the coordinate (I, J-2) is regarded as an edge point. However, if a = EYEIN + 4, EYE
MIN is the lowest luminance value in the image data until the current sequential processing.

The values of C3 and C4 are, for example, C3 =
3, C4 = 20.

The above condition is characterized in that there is a predetermined brightness difference continuously at the pupil edge (border between the iris and the pupil), and at the same time, the pupil part has the lowest brightness in the eyeball reflection image. . Above 1. And 2. The condition (3) is that the edge of the area sensor 17 in the lateral direction (X axis) is extracted, and the above 3. And 4. The condition is to extract edges in the vertical direction (Y axis).

When the coordinate (I, J-2) is extracted as the pupil edge point, steps # 303 to #
The flow branches to 305 to store the brightness value and coordinates of the edge point.

In step # 305, information is stored in the array variable EDGDT (m, k) for storing edge position information as follows.

EDGDT (EDGCNT, 1) ← IM (I, 2) EDGDT (EDGCNT, 2) ← I) EDGDT (EDGCNT, 3) ← J-2 Note that IM (I, 2) was detected at the EDGCNT position. The brightness of the edge point, I is the same X coordinate, and (J-2) is the same Y coordinate.

Then, the variable EDGCNT for counting the number of detected edge points is incremented by one.

When the process of step # 305 ends, the loop variable I (lateral direction, which represents the coordinate of the X axis) of the outer loop process is counted up, and the flowcharts of step # 302 and thereafter are executed again.

Now, a case will be described in which it is determined in step # 302 that there is an edge point near the current coordinate (I, J-2).

In this case, the process branches to step # 304, and as in step # 303, the image data of the coordinates (I, J-2) currently to be verified is the condition of the pupil edge (the judgment condition in step # 304). Is described as “edge condition 2”).

Here, the “edge condition 2” is set so to speak, as it were, than the “edge condition 1”. In this embodiment, the values C3 and C4 are the same as in the conditional expression,
3 ', C4', and changed as follows.

By setting C3 '= 2 and C4' = 30, the rate of being judged as an edge is improved as compared with "edge condition 1".

The reason for preparing two types of edge judgments in this way is that edge points do not exist independently in the first place but are continuous, and if a certain point is an edge point, its vicinity is It is based on the viewpoint that they are likely to be at the same edge point.

If the edge point is determined in the "edge condition 2" of step # 304, the process branches to step # 305 and the information of the coordinates is stored.

As described above, the loop variable I is "14".
The loop process of step # 301 is executed until the number becomes 9 ″, and when the edge detection process for one line in the horizontal direction (X axis) of the area sensor 17 is completed, the process proceeds to step # 306, and the subroutine “pupil edge "Detection" is returned.

Returning again to the description of FIG.

When the subroutine "pupil edge detection" in step # 062 is completed, the loop variable J in the outer loop processing step # 058 (vertical direction of the area sensor 17,
Counts up (representing the Y-axis coordinate) and J is "99"
The processings of step # 059 and thereafter are executed again until it becomes.

When the loop variable J becomes "99" and the reading and processing of the designated pixel by the area sensor 17 are completed, the process proceeds from step # 058 to step # 062.

In steps # 063 to # 065, the center coordinates of the pupil and the line of sight are detected from the P image position and the pupil edge information detected in the loop processing of step # 058.

First, in step # 063, a subroutine "pupil estimation range setting" is called.

In addition to the edge points that actually represent the pupil circle (the circle formed by the boundary between the iris and the pupil), the plurality of pupil edge points detected by the "pupil edge detection" subroutine of step # 062 , False edge points caused by various noises are also included.

The "pupil estimation range setting" is a subroutine for limiting the probable edge point coordinate range based on the P image position information in order to eliminate the false edge points. As shown in FIG. 12, this will be described below.

When the subroutine "pupil estimation range setting" is called, through step # 400, step # 4
Execute 01.

In step # 401, the P image position range described previously in the "P image detection" subroutine, that is, IP1 to IP2 in the horizontal direction (X axis) and JP in the vertical direction (Y axis).
Using the information of 1 to JP2, the pupil circle coordinate range IS1,
IS2, JS1, and JS2 are calculated according to the following formula.

IS1 ← IP1-20 IS2 ← IP2 + 20 JS1 ← (JP1 + JP2) / 2-20 JS2 ← (JP1 + JP2) / 2 + 40 Probable pupil edge points are in the lateral direction (X axis) range IS1 to IS2 of the area sensor 17. It is set as a point existing in the range JS1 to JS2 in the vertical direction (Y axis).

In the optical system of this embodiment, as shown in FIG. 6 (A), the two P images are always present in the upper part of the circle of the pupil circle. To establish.

After the calculation in step # 401, the process proceeds to step # 402, and the subroutine "set pupil estimation range" is returned.

Returning to FIG. 8, the subroutine "pupil center detection" in step # 062 is called next.

"Detection of pupil center" is a subroutine for estimating the shape (coordinates and size of the center) of the pupil circle from the coordinates of probable pupil edge points, and the flowcharts thereof are shown in FIGS.

For estimating the shape of the pupil circle, the “least square method” is used.
Is used. I will explain the idea first.

As is well known, the circle formula is given by (X−a) ² + (Y−b) ² = C ² (10) where the center coordinates are (a, b) and the radius is c. To be

A plurality of observation points (x1, y1), (x2, y
2) Considering that a, b, and c are determined from (xn, yn) so that the error amount ER in the following equation is minimized.

ER = Σ [(xi−a) ² + (yi−b) ² −C ² ] ... (11) ER is the normal direction of the circle determined by each observation point and a, b, c. It is the sum of squares of the distance (error) and minimizes this.

ER is partially differentiated by a, b, and c, and is set to 0.

ΔER / δa = Σ [-4 (xi-a) ³ -4 (xi-a) (yi-b) ² + 4c ² (xi-a)] = 0 (12) δER / δb = Σ ^{[-4 (xi-b) 3} -4 (xi-a) 2 (yi-b) + 4c 2 (xi-b)] = 0 ...... (13) δER / δc = Σ [-4c 3 -4 (yi ^{-b) 2 c + 4c (xi} -a) 2] = 0 ...... (14) where the f = 1~ny.

From the above equation (14), δER / δc = ΣC ² = Σ [(xi-a) ² + (yi-b) ² ] / n = 0 (15) The above equation (15) is changed to the equation (15). 13) and (14), where X1 = Σxi ... (16) X2 = Σxi ² (17) X3 = Σxi ³ (18) Y1 = Σyi (19) Y2 = Σyi ² (20) Y3 = Σyi ³ (21) Z1 = Σxiiy (22) Z2 = Σxi ² yi (23) Z3 = Σxii ² (24) Further, V1 = X2-X1 ² / n (25) V2 = Y2-Y1 / n (26) W1 = X3-Z3 (27) W2 = Y3-Z3 (28) W3 = (X2 + Y2) / n (29) W4 = Z1-X1Y1 / n (30) W5 = (Z1- 2 · X1Y1 / n) Z1 (31) W6 = X1Y2 (32) W7 = X2Y1 (33) When arranged as follows, the center coordinates a and b of the circle are a = {W1V2-W2W4 -(W6-Y1Z1) W3} / 2 (X2V2-W5-W6X1 / n) ... (34) b = {W2V1-W1W4- (W7-Y1Z1) W3} / 2 (X2V2-W5-W7X1 / n) … Calculated by (35).

[0189] Also, although not directly related to the calculation of the line of sight (fixation point), the radius c is calculated as c = {W3-2 (aX1 + bY1 ) / n + a 2 + b 2} 1/2 ... (36).

In the embodiment of the present invention, the error amount E is further added.
R is used for the reliability determination of pupil center detection, and ER is given by the following equation.

[0191] ^{ER = X4-4aX3 + 2 (2a 2} + d) X2-4adX1 + Y4-4bY3 + 2 (2b 2 + d) Y2-4dbY1 +2 (Z4-2aZ3-2bZ2 + 4abZ1) + d 2 n ......... (37) However, X4 = Σxi ⁴ (38) X4 = Σyi ⁴ (39) Z4 = Σxi ² yi ² (40) d = a ² + b ² + c ² (41)

Now, the flowcharts of FIGS. 13 to 15 will be described in accordance with the above-described proof of the numerical calculation.

When the subroutine "pupil center detection" is called, the "circle least square estimation" subroutine of step # 501 is called after step # 500 shown in FIG.

"Least square estimation of circle" is a subroutine for calculating the ER of the central coordinates (a, b) of the pupil circle and the error amount according to the above equation, and its flowchart is shown in FIG. explain.

In the same sub-routine, the minimum luminance is further reviewed and the false pupil edge due to the P image is eliminated.

When the subroutine "least square estimation of circle" is called, the process goes through step # 600 to step # 60.
Move to 1.

At step # 601, the work variables of the above least squares estimation formula are initialized. The next step # 602 is a loop process in which the variable L is a loop variable, and is the part that performs the first half of the least squares method calculation based on the stored pupil edge information.

Now, as the pupil edge point, (EDGCN
T-1) pieces of information are stored in the array variable EDGDT. The loop variable L represents the stored order.

At the first step # 603 in the loop processing, the brightness values EDGDT (L, 1) of the Lth edge point are compared with (EYRMIN + C5), and if the brightness value is larger, the process branches and the current leap variable is reached. The process of L is completed.

In this embodiment, since the photoelectric conversion signal of the area sensor 17 is read and the sequential processing is performed, the lowest luminance value used in the edge point detection portion is also the lowest until that point. It is just a brightness value.

Therefore, the points detected as edge points are also
Actually, it is not determined by the true minimum luminance value, and there may be a point that is actually not suitable as an edge point. Therefore, the purpose of this step is to determine the lowest luminance value again based on the finally determined lowest luminance value, and to eliminate points that are not suitable as pupil edges.

The value C5 is, for example, C5 = 20.

If it is determined in step # 603 that the luminance value is small, the process proceeds to step # 604), and the horizontal (X-axis) coordinates and the vertical (Y-axis) coordinates are set to variables X and Y, respectively. Store temporarily.

In the next step # 605, it is determined whether or not the horizontal coordinate X of the L-th edge point is within the horizontal range IS1-IS2. IS1 and IS2 are values obtained by the subroutine "setting of pupil estimation range". Edge points that are not within this range are branched so as not to be recognized as edge points of the pupil, and the processing of the current loop variable L ends. To do.

At the next step # 606, the same judgment is made in the vertical direction. If the L-th edge point exists in the pupil estimation range, the process proceeds to step # 607.

Steps # 607 and # 608 are
It is determined whether the coordinates of the L-th edge point are near the P image.

XP1, XP2, YP1 and YP2 are values determined in the subroutine "P image detection", and the coordinates of the edge points are in the horizontal directions XP1 to XP2 and the vertical range Y.
If it is in P1 to YP2, the process branches to end the processing of the current loop variable L.

This is because in the optical system of the present embodiment, two P images are present in the upper part of the pupil circle, so that the "tail" of the P image having a spot image shape is formed. This is because it is easy to meet the above-mentioned condition of the pupil edge, and it is excluded that the portion is detected as a false pupil edge.

The coordinate information of the edge point that has passed the above determinations in steps # 603 to # 608 is used for the calculation of the least squares method in step # 609.

The calculation in step # 609 is performed by the above equation (1
6) to (24) and (38) to (40) are executed, and the number N of edge points used in the calculation is counted up.

When all the stored edge points (EDGCNT-1) have been completed in the loop processing of step # 602, the routine proceeds to step # 610.

At step # 610, equations (25) to (3)
5), (37) to (41) are calculated to obtain the center coordinates (a, b) of the pupil circle and the error ER.

Then, the process proceeds to the next Step # 611,
The subroutine "least square estimation of circle" is returned.

Returning to FIG. 13, when the subroutine "estimation of least squares of circle" in step # 501 is returned, the process proceeds to the next step # 502.

At step # 502, the number N of data used for estimating the circle is compared with the value NTHR, and N <NTHR.
If so, it is considered that the reliability of the result is low because the number of data is small, and the process branches to step # 512 and the detection fails. As the NTHR, for example, NTHR = 30.

If N ≧ NTHR in step # 502, the error amount ER and the value ERT are calculated in the next step # 503.
Compare HR. As a result, if ER <ERTHR,
Considering that the error amount is small and the detection result is sufficiently reliable, the process branches to step # 514 and the detection is successful. As the value ERTHR, for example, ERTHR = 10
000.

At step # 503, ER ≧ ERY
If it is HR, it is assumed that the error is too large even though the number of data is sufficient, and the recalculation from step # 504 onward is executed.
The reason why the error becomes large may be that false edge points other than the pupil circle are included in the calculation.

Therefore, among the coordinates of each edge point, the edge point at the end coordinate in the vertical / horizontal direction is excluded from the calculation, and it is investigated whether or not the error is reduced.

At step # 504, the subroutine "least square estimation recalculation 1" is called.

The "least square estimation recalculation 1" is the area sensor 1 among the edge points used for the least square estimation calculation.
This is a subroutine for excluding the edge points (⅕ of the whole) at the upper part of the vertical direction of 7 and performing the calculation of the least squares method again, and its flowchart is shown in FIG. 15, which will be described below.

When the subroutine "circle least squares estimation recalculation 1" is called, step # shown in FIG.
After 700, variables are stored in the next step # 701 as shown in the figure.

Variables XS1 to ZS4 are set in step # 501.
The values of the corresponding work variables when all the edge points calculated in step 3 are used are stored. Then, the number of edge points to be excluded is stored in the variable M as ⅕ of the number N of all edge points.

At the next step # 702, the same calculation work as at step # 601 is initialized, and step #
Move to 703. Step # 703 is a loop process similar to step # 602, and the least squares method of the edge points to be excluded in this loop is calculated.

In the embodiment of the present invention, the area sensor 1
Since 7 is read from the upper part in the vertical direction, the array variable EDGDT (m, k) storing the edge information is sequentially stored from the upper edge in the vertical direction. Therefore, if m of EDGDT (m, k) is counted up from 0, it is possible to take a picture from the edge point in the vertical direction.

Now, in the first step # 704 in the loop of step # 703, it is judged whether or not the edge point (X, Y) is effective as a pupil edge. This is exactly the same as steps # 603 to # 608. It is the same.

If the pupil edge point is considered to be effective, the process proceeds to step # 705, which is also performed at step # 705.
Perform the same calculation as 609.

Then, in the next step # 706, the number N of newly calculated edge points is compared with the number M of edge points to be excluded, and when the calculation of M pieces is completed, the process branches to the outside step. The loop process of # 703 is stopped. If the number has not reached M, the loop variable L is counted up,
The process of moving to step # 704 again is continued.

When M calculations are completed, step # 708.
And the center (a, b) of the pupil circle and the error amount ER 'are recalculated.

The formula for recalculation is as follows.

X1 = X1S-X1 (16 ') X2 = X2S-X2 (17') X3 = X3S-X3 (18 ') Y1 = Y1S-Y1 (19') ) Y2 = Y2S-Y2 (20 ') Y3 = Y3S-Y3 (21') Z1 = Z1S-Z1 (22 ') Z2 = Z2S-Z2 (23') Z3 = Z3S-Z3 ... (24 ') X4 = X4S-X4 ... (38') Y4 = Y4S-Y4 ... (39 ') Z4 = Z4S-Z4 ... (40') By recalculating (25) to (35) and (37) to (41), the new pupil center (a, b) and the error amount ER are calculated.
´ can be obtained. Since equations (16) to (40) are originally in a sequential form, it is not necessary to recalculate all data, and addition (or power addition) of data to be excluded is calculated and subtracted from the base value. I'm done.

After recalculation is completed, step # 709.
And the subroutine "least squares circle recalculation 1" is returned.

Returning to FIG. 13, when step # 504 is completed, the process proceeds to step # 505, and the recalculated error amount ER 'is compared with the value ERTHR. If ER 'is small, it is determined that the exclusion operation is effective, and step # 51 is performed.
It branches to 4 and the detection is successful.

If the error amount ER 'is still large, the routine proceeds to step # 506, and another subroutine "minimum circle 2
Call the power estimation recalculation 2 ".

The "least square estimation recalculation 2" excludes the edge points (1/5 of the whole) located vertically below the area sensor among the edge points used for the least square estimation calculation. This is a subroutine for calculating the least squares estimation again, and its flowchart is shown in FIG.

"Recalculation 2" is almost the same as "Recalculation 1", but unlike "Recalculation 1", it is excluded from the lower edge point in the vertical direction. Therefore, in step # 712, the loop variable is calculated. L is down-counted from (EDGCNT-1). Others are exactly the same as “Recalculation 1”, and thus the description is omitted.

Returning to FIG. 13 again, the description will be continued.

When the subroutine "least squares circle recalculation 2" of step # 506 is completed, step # 50
7, the recalculated error amount ER 'is compared with the value ERYHR. If ER 'is small, it is determined that the exclusion operation is valid, and the process branches to step # 514, and it is considered that the detection is successful.

When the subroutine "recalculation 3" is called, in step # 721 of FIG. 15C, the array variable ED storing the edge information is processed in step # 721.
Rearrange GDT (m, k).

As described above, EDGDT (m,
In k), the data are stored in order from the edge points in the vertical direction of the area sensor 17, so that the data stored in the EDGDT needs to be rearranged in order to perform processing while paying attention to the horizontal direction.

Since the value of the edge point in the horizontal direction (X-axis coordinate) is stored in EDGDT (m, 2), if a known "sort operation" is performed on this value, EDGDT has a horizontal value. It is possible to restore the edge information in the order from the left of the direction.

When the rearrangement is executed, the process branches to step # 702 in FIG. 15A, and if the same process as "Recalculation 1" is performed thereafter, the edge points on the left and right in the horizontal direction of the area sensor 17 are excluded. Can be recalculated.

Returning to FIG. 13 again, when the subroutine "circle least squares estimation recalculation 3" of step # 508 is completed, the process proceeds to step # 509, and the recalculated error amount ER is calculated.
'And the □ value ERTHR are compared. If ER 'is small, it is determined that the exclusion operation is effective, and step # 514
It branches to and is regarded as a detection success.

If the error amount ER 'is still large, the routine proceeds to step # 510, and another subroutine "circle least square estimation recalculation 4" is called.

In the “least square estimation recalculation 4”, the edge points at the right side in the lateral direction of the area sensor 17 (1/1 / of the whole) among the edge points used in the calculation of the least square estimation are calculated.
This is a subroutine for excluding step 5) and calculating the least squares estimation again, and its flowchart is shown in FIG.

Since the array variable EDGDT (m, k) stores the edge points in order from the left in the horizontal direction, if the edge points are to be excluded in order from the right, EDG will be stored.
DT (m, k) may be scattered and treated in the same manner as “Recalculation 2”. Therefore, when the subroutine "recalculation 4" of FIG. 15D is called, the process immediately branches to step # 711 and the same processing as "recalculation 2" is performed.

Returning to FIG. 13 again, the description will be continued.

When the subroutine "least squares circle recalculation 4" of step # 510 is completed, step # 51
The process proceeds to 1 and the recalculated error amount ER 'is compared with the value ERTHR. When ER 'is small, it is determined that the exclusion operation is valid, and the process proceeds to step # 512 and it is considered that the detection is successful.

If the error amount ER 'is still large, the process proceeds to step # 512, and it is determined that the above-mentioned operation did not work effectively and the detection fails.

Step # 512 or Step #
When the final determination of the pupil center detection is made in 514, the process proceeds to step # 515, and the subroutine "pupil center detection" is returned.

FIG. 16 shows an example of the least squares method according to the embodiment of the present invention.

The black portion in the figure indicates one edge point, and the pupil circle is estimated based on these edge points.

Returning to the description of FIG.

[Detection of pupil center] in step # 064
Is completed, the process proceeds to step # 065 to call a subroutine "line of sight detection".

"Detection of line of sight" is a subroutine for detecting the line of sight (gazing point) from the P image position and the center position of the pupil circle detected by the above processing.

Basically, the rotation angle θ of the optical axis of the eyeball may be calculated according to the equation (2) as in the known example described above.
In the embodiment of the present invention, the center of the pupil is set in the lateral direction (X axis),
Since the detection is performed two-dimensionally in the vertical direction (Y axis), not only the horizontal direction as in the known example but also the direction of the line of sight in the vertical direction can be detected by the same idea as the detection in the horizontal direction.

When the detection of the line of sight is completed, step # 06
6, the series of processing for detecting the line of sight is terminated.

(Second Embodiment) The single lens reflex camera according to the second embodiment of the present invention will be described in detail below. Since the optical and electrical configuration of the camera is the same as that of the first embodiment, the description thereof will be omitted here.

FIG. 17 is a flowchart showing the main operation of the camera in the second embodiment of the invention.

In FIG. 17, the same steps as those in FIG. 7 are given the same step numbers. Therefore, here, in FIG.
The processing different from that will be mainly described.

Steps # 001 to # 012 in which the mode dial 44 is turned on are the same as those in FIG.
It detects that the switch SW1 is closed and turned on (step # 003), and performs photometric processing and the like (step # 012).

At step # 014, it is checked whether the flag SW1F is "0". When SW1F is not "0", the process proceeds to step # 015 to detect the line of sight, and subsequently, at step # 016, the distance measuring point is selected, and then it is checked whether or not the switch SW1 is on.

The processing contents of step # 015, step # 016, and step # 017 are the same as those in FIG. 7 described above.

When the flag SW1F is "0" in step # 014, the process proceeds to step # 017 to check whether or not the switch SW1 is on. And
When the switch SW1 is not on, the above step #
The process moves to 015 to detect the line of sight.

When the switch SW1 is "0" in step # 017, the process shifts to step # 021 to perform the series of AF processes described above.

The line-of-sight detection subroutine of step # 015 has the same processing contents as in the first embodiment shown in FIGS. 8 to 15, and therefore its explanation is omitted here.

The above is the description of the operation of FIG.

As described above, the transistor PTR113 is turned off and the switch S is turned off from the state where the power supply is stopped.
When W1 is turned on, line-of-sight detection (step # 01
5), focus detection point selection (step # 016), AF (step # 021), and the like. When power is once supplied and the process branches from step # 043 to step # 011, the process is performed immediately before. Since the previous line-of-sight detection result can be used, whether the branch from step # 043 or not is determined from the result of the flag SW1F in step # 014.

If the switch SW1 is turned on in step # 017, the process proceeds to step # 021 in order to perform a series of AF processing by the distance measuring point selected based on the result of the previous line-of-sight detection performed immediately before. The processing is executed in the operation flow of the camera of the second embodiment.

As a modification, step # 011,
During execution of each process of step # 015, step # 016), it is checked whether or not the switch SW1 is on at a predetermined interval or during a predetermined process operation. If not, the process proceeds as it is, and the switch is turned on. There is also a method of stopping the process at some time and shifting to step # 021.

According to each of the above embodiments, since the visual axis detecting operation is repeatedly performed at a predetermined interval while the timer is operating, a camera equipped with a visual axis detecting device that minimizes the time until the shutter release is realized. it can.

Further, since the line-of-sight detection operation is repeatedly performed at a predetermined interval while power is being supplied, it is possible to realize a camera in which it is hard to miss a photo opportunity.

Further, once the switch SW1 is turned on,
Since the line-of-sight detection operation is repeatedly performed during a predetermined period, when applied to a camera having an autofocus function, the switch SW1 is turned on when the release button is pressed and a series of lens focusing control is performed. At this time, the distance measuring point is selected based on the sight line detection information detected immediately before the switch SW1 is turned on, and the focus adjustment is performed, so that the decrease in the responsiveness due to the sight line detecting operation is minimized and the sense of discomfort is felt. It is possible to provide a camera that can be used without worry.

(Correspondence between Invention and Embodiment) In the first and second embodiments described above, the switch SW1 serves as a first switch means which is closed by pressing the release button 41 up to the first stage. Correspondingly, the switch SW2 corresponds to the second switch means that is closed by pressing the release button 41 up to the second stage, and the line-of-sight detection circuit 101 and the CCD-E.
YE14 corresponds to the line-of-sight detection means, and the automatic focus detection circuit 1
03 and the line sensor 6f correspond to means for performing focus adjustment, and include a power supply circuit 111 and a power supply transistor PTR.
Reference numeral 113 corresponds to a power supply means, and PRS100 corresponds to a control means.

The above is the correspondence relationship between each configuration of the embodiments and each configuration of the present invention, but the present invention is not limited to the configurations of these embodiments, and the functions shown in the claims can be achieved. It goes without saying that any structure may be used.

Further, the present invention can be applied to any area sensor composed of a plurality of photoelectric conversion element rows regardless of the number of pixels and the number of lines forming the area sensor.

The present invention is not limited to single-lens reflex cameras,
A lens shutter camera, a video camera, an optical device other than the camera, or any other device having a line-of-sight detection device can be applied.

[0277]

As described above, according to the present invention,
By closing the first switch means for starting the photographing preparation operation and supplying power, the visual axis detection operation is repeatedly performed, and the focus detection position at which the visual axis is input is monitored while the power is being supplied. Then, the photographing operation can be started immediately when the second switch means is closed. In other words, even if the first switch means is closed again to perform the photographing operation, the visual axis detection means is not newly activated from the beginning, but repeated visual axis detection is performed while power is being supplied. In addition, the accumulation time for detecting the line of sight at this time is shortened.

Therefore, the release time lag when the release button is operated for the purpose of starting the photographing operation is minimized, and the camera with the line-of-sight detection function which is strong against the shutter chance can be obtained.

Further, according to the present invention, the line-of-sight detection operation is repeatedly performed for a predetermined time after the first switch means for starting the photographing preparation operation is closed, and during this predetermined time. The focus detection position for line-of-sight input is continuously monitored, and the photographing operation can be started immediately when the second switch means is closed. That is, even if the first switch means is closed again to perform the photographing operation, the visual axis detection means is not newly activated from the beginning, but the visual axis detection is repeatedly performed for a predetermined time. It should be noted that the accumulation time for detecting the line of sight at this time is shortened.

Therefore, the release time lag when the release button is operated for the purpose of starting the photographing operation is minimized, and the camera with the line-of-sight detection function which is strong against the shutter chance can be obtained.

Further, according to the present invention, when the first switch means is closed again, in most cases, the release button is pressed all at once until the second switch means is closed. In other words, in other words, since it is almost the case that the release button operation is intended to start the shooting operation, the line-of-sight detection is not performed when the first switch means is closed this time,
The focus detection position is determined using the line-of-sight detection result performed immediately before, and focus adjustment is performed based on the focus detection information obtained here.

Therefore, even when the focus detection position is selected by the line of sight, the shooting process can be advanced with substantially the same responsiveness as in the case where the focus detection position is automatically determined and the shooting process is advanced. ..

[Brief description of drawings]

FIG. 1 is a configuration diagram showing a main part of a single-lens camera camera according to an embodiment of the present invention.

FIG. 2 is a diagram showing a top surface and a back surface of the single-lens camera of FIG.

3 is a diagram showing the inside of a viewfinder of the single-lens camera of FIG.

FIG. 4 is a block diagram showing an electrical configuration of the single-lens camera of FIG.

FIG. 5 is a diagram for explaining the principle of line-of-sight detection.

FIG. 6 is a diagram showing a main part of an eyeball image and a signal level.

7 is a flowchart showing a main operation of the single-lens camera of FIG.

8 is a flowchart showing an operation of "visual axis detection" executed in step # 015 of FIG. 7. FIG.

9 is a flowchart showing an operation of "reading one line" executed in step # 059 of FIG.

10 is a flow chart of "P" executed in step # 061 of FIG. 8;
7 is a flowchart showing an operation of "image detection".

FIG. 11 is a flowchart showing an operation of “pupil edge detection” executed in step # 062 of FIG. 8;

FIG. 12 is a flowchart showing an operation of “pupil estimation range setting” executed in step # 063 of FIG. 8;

FIG. 13 is a flowchart showing an operation of “pupil center detection” executed in step # 064 of FIG. 8;

14 is a flowchart showing the operation of "estimation of least square of circle" executed in step # 501 of FIG.

FIG. 15 shows steps # 504, # 506, and # 5 of FIG.
It is a flowchart which shows operation | movement of "the least square estimation recalculation 1, recalculation 2, recalculation 3, recalculation 4 of a circle" performed in 08, # 510.

FIG. 16 is a diagram showing an example of a least squares method.

FIG. 17 is a flowchart showing a main operation of the single-lens reflex camera according to the second embodiment of the present invention.

[Explanation of symbols]

 11 Eyepiece Lens 14 Image Sensor 25 Illumination LED 41 Release Button 100 PRS 101 Line-of-Sight Detection Circuit 103 Focus Detection Circuit 110 Focus Adjustment Circuit 112 Power Supply Circuit 113 Power Supply Transistor (PTR)

Claims (3)

[Claims] 1. A first switch means for starting a photographing preparation operation which is closed by pressing the release button up to the first stage,
A camera with a line-of-sight detection function, comprising: a second switch unit for starting a photographing operation, which is closed by pressing the release button up to the second stage, and a line-of-sight detection unit for detecting a line of sight. When the power supply is started, the power supply is started, and when a predetermined time has elapsed, the power supply is stopped and the line-of-sight detection unit repeatedly detects the line-of-sight while the power is being supplied. A camera with a line-of-sight detection function, characterized in that it is provided with a control means for performing. 2. A first switch means for starting a photographing preparation operation, which is closed by pressing the release button up to the first stage,
A camera with a line-of-sight detection function, comprising: a second switch unit for starting a photographing operation, which is closed by pressing the release button up to the second stage, and a line-of-sight detection unit for detecting a line of sight. When closed, the timekeeping operation is started, and the timekeeping means ends the operation after a predetermined time is counted, and while the timekeeping operation is being performed by the timekeeping means, the eye gaze detecting means repeatedly detects the line of sight. A camera with a line-of-sight detection function, which is provided with control means for performing detection. 3. A first switch means for starting a photographing preparation operation which is closed by pressing the release button up to the first step,
A camera with a line-of-sight detection function, comprising: a second switch unit for starting a photographing operation, which is closed by pressing the release button up to the second stage, and a line-of-sight detection unit for detecting a line of sight. By being closed, the line-of-sight detection means is made to repeatedly perform line-of-sight detection at predetermined intervals,
When the first switch means is closed again during the repeated line-of-sight detection, the focus detection position is determined using the result of the line-of-sight detection performed immediately before, and the focus detection information is obtained. A camera with a line-of-sight detection function, which is provided with control means for calculating and performing focus adjustment based on this.