JPH0846833A - Camera with line of sight detecting function - Google Patents

Abstract

PURPOSE:To reduce the fatigue of a photographer also to confirm an AF/AE area for execution of line of sight trackjng AF/AE function by displaying/ erasing an AF/AE area frame showing the AF/AE area on a finder screen in response to the operating environment. CONSTITUTION:The objects can be focused in the AF/AE areas 2 and 3 and also the AE is performed in these areas. At the same time, an AF/AE area frame 3a is shown at watch point and the areas 2 and 3 always move in reponse to the shift of line of sight. In a normal line of sight tracking mode, the AF/AE can be performed on a finder display screen 1 at watch point with no display of the frame 3a. Then the areas 2 and 3 are fixed when line of sight AF/AE frame lock SW is pushed. In an AF/AE area lock mode, the frame 3a is shown in a finder.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a camera having a visual axis detecting function, such as a video camera or a still camera having a visual axis detecting function.

[0002]

2. Description of the Related Art Conventionally, a camera such as a video camera or a still camera, which is provided in a viewfinder screen of these cameras, selects an index indicating a function such as zoom or fade with a line of sight to execute the function. There has been proposed a line-of-sight detection device used for a so-called line-of-sight input function, such as focusing on a gazing point on the finder screen. Hereinafter, one of the principles of this visual axis detection device will be described.

FIG. 5A is a principle view (top view) of the visual axis detection method, and FIG. 5B is a principle view (side view) of the visual axis detection method.

In FIGS. 5A and 5B, 506a,
Reference numeral 506b is a light source such as a light emitting diode (IRED) that emits infrared light that is insensitive to the observer, and each light source is substantially symmetrical to the optical axis of the imaging lens 511 in the x direction (horizontal direction) ( (See FIG. 5A), and slightly below the y direction (vertical direction) (see FIG. 5B), the observer's eye 508 is divergently irradiated. A part of the illumination light reflected by the eyeball 508 is imaged by the image forming lens 511.
Image on 12. FIG. 6A shows an image sensor 512.
FIG. 6B is an output intensity diagram of the image sensor 512. FIG.

A method of detecting the line of sight will be described below with reference to the drawings. Considering the horizontal plane first, in FIG.
The infrared light emitted from 06b illuminates the cornea 510 of the eyeball 508 of the observer. At this time, the cornea reflection image d (virtual image) formed by the infrared light reflected on the surface of the cornea 510 is condensed by the imaging lens 511, and the image sensor 51
The image is formed at the position d'on the position 2. Similarly, the infrared light emitted from the light source 506a illuminates the cornea 510 of the eyeball 508.
At this time, the corneal reflection image e (virtual image) formed by the infrared light reflected on the surface of the cornea 510 is the imaging lens 511.
The light is condensed by the image sensor and forms an image at a position e ′ on the image sensor 512.

Light fluxes from the edges a and b of the edge portion 602 of the pupil 601 surrounded by the rainbow sample 504 (604 in FIG. 6) are transmitted through the image forming lens 511 to the image sensor 51.
The images of the edges a and b are formed at the positions a ′ and b ′ on the position 2. When the rotation angle θ of the optical axis of the eyeball 508 with respect to the optical axis of the imaging lens 511 is small, assuming that the x-coordinates of the edges a and b of the pupil 601 are xa and xb, a large number of xa and xb are obtained on the image sensor 512. It is possible (Fig. 6 (a))
(See the cross mark inside). Therefore, first, the pupil center xc603 is calculated by the method of least squares of the circle or the like. On the other hand, when the x coordinate of the center of curvature o of each film 510 is xo, the rotation angle θx of the eyeball 508 with respect to the optical axis is

## EQU1 ## oc * sin θx = xc−xo. Further, when xo is calculated in consideration of a predetermined correction value δx at the midpoint k of the corneal reflection images d and e,

## EQU00002 ## xk = (xd + xe) / 2 xo = (xd + xe) /2+.delta.x. Here, δx is a numerical value geometrically obtained from the installation method of the device, the eyeball distance, etc., but the calculation method is omitted.

Therefore, by substituting equation 1 into equation 2 to obtain θx,

## EQU00003 ## .theta.x = arcsin [[xc-{(xd + x
e) / 2 + δx}] / oc], and the coordinates of each feature point projected on the image sensor 512 are added with a “′” (dash) to form θ.
Rewriting x,

## EQU00004 ## .theta.x = arcsin [[xc '-{(xd' +
xe ′) / 2 + δx ′}] / oc / β].

Here, β is a magnification determined by the distance sze of the eyeball 508 with respect to the imaging lens 511, and is actually obtained as a function of the interval | xd'-xe '| of corneal reflection images.

Considering the vertical plane, the structure is as shown in FIG. That is, two light sources (IRED) 506
The corneal reflection image generated by a and 506b is generated at the same vertical position, and is referred to as yi. Although the method of calculating the rotation angle θy of the eyeball 508 is almost the same as that for the horizontal plane, only the formula 2 is different, and if the y coordinate of the corneal curvature center o is yo,

(5) yo = yi + δy.

Here, δy is a numerical value obtained geometrically from the device arrangement method, eyeball distance, etc., and its calculation method is omitted. Therefore, the vertical rotation angle θy is

Θy = arcsin [[yc ′ − (yi ′ + δ
y ')] / oc / β]. Note that yc 'is a coordinate on the image sensor 512 in the vertical direction of the center of the pupil.

Further, for the position coordinates (xn, yn) on the finder screen of the camera, if a constant m determined by the finder optical system is used, then on the horizontal plane and the vertical plane respectively.

Xn = m * arcsin [[xc '-{(x
d ′ + xe ′) / 2 + δx ′}] / oc / β]

Yn = m * arcsin [[yc '-{(y
i ′ + δy ′)] / oc / β].

As is apparent from FIG. 6B, the detection of the pupil edge 602 utilizes the rising edge (xb ') and the falling edge (xa') of the output waveform of the image sensor 512. The coordinates of the corneal reflection image use sharp rising portions (xe 'and xd').

Next, an example of a video camera with a visual axis detection function will be described. FIG. 7 is a schematic configuration diagram showing an example of a video camera with a line-of-sight function.

The video camera shown in FIG. 7 has a camera lens group 714, a diaphragm 715, an AF motor 716, a lens optical system 713 for picking up an object, and the diaphragm 715.
A diaphragm drive circuit 712 that drives the AF motor 716 and an AF motor drive circuit 711 that drives the AF motor 716.

A lens image pickup system 70 having an image pickup element
1, a finder 703 for observing an object imaged by the lens imaging system 701 on the finder screen 702, an eyepiece 704 arranged in front of the finder 703, and a line of sight for detecting the line of sight of a photographer's eye 705. A detection unit 706, an AF frame that indicates the outline of the focus area, a display circuit 707 that displays information such as an index of a line-of-sight switch, which will be described later, and other information necessary for the photographer such as a tape counter and a photographing mode on the finder screen 702.
A line-of-sight AF frame lock switch 710 for temporarily fixing the frame and a system controller 708 for controlling each unit of this camera are provided.

The line-of-sight detection unit 706 includes an infrared light emitting diode 760 that irradiates the photographer's eye 705 with infrared light, and a dichroic mirror 761 that transmits visible light and reflects infrared light.
And a condenser lens 762 for condensing the infrared light reflected by the dichroic mirror 761 and the condenser lens 7
An image pickup element 763 for converting the infrared light condensed by 62 into an electric signal, and a photographer's eye 70 on the image pickup element 763.
It also includes a gazing point detection circuit 764 that finds a gazing point on the finder screen 702 of the photographer based on the image of FIG.

Since the dichroic mirror 761 transmits visible light, the photographer can observe the viewfinder screen 702 through the eyepiece 704. Further, since the dichroic mirror 761 reflects infrared light, it reflects the reflected image of the eye 705 irradiated by the infrared light emitting diode 760. Then, the reflected image of the eye 705 is condensed by the condenser lens 762 and imaged on the image sensor 763.

The gazing point detection circuit 764 is based on the image of the photographer's eye 705 formed on the image pickup element (photoelectric conversion element) 763, the above-mentioned principle, and Japanese Unexamined Patent Publication Nos. 1-241511 and 1-21511. A photographer's viewfinder screen 702 is displayed according to the algorithm disclosed in Japanese Patent Publication No. 2-332312.
It seeks the above point of attention.

Next, the line-of-sight AF / AE function will be described. Based on the gazing point information detected by the line-of-sight detection unit 706, the AF motor driving circuit 711 focuses the area near the gazing point (AF), and the diaphragm driving circuit 712 controls the exposure (AE). Here, during AF control, the AF motor drive circuit 711 is operated so that the high frequency component of the image signal output from the lens imaging system 701 reaches a peak.

Further, line-of-sight AF / AE frame lock SW71
By pressing 0, the AF / AE frame can be fixed at the gaze point coordinate position at that time. As a result, when the subject is fixed, it is not necessary to keep an eye on the subject and eye fatigue can be prevented.

Further, during the line-of-sight AF / AE operation, the line-of-sight tracking AF / AE is displayed on the finder screen as shown in FIG.
Although the AE frame 801 is displayed, this line-of-sight tracking AF / AE
Since the frame 801 moves in accordance with the information on the gazing point as indicated by the broken line arrow in the figure, it can be confirmed that the AE / AF is operating near the gazing point.

[0022]

However, in the configuration of the conventional example, the line-of-sight tracking AF / AE frame is always displayed in the viewfinder, which makes the photographer feel annoyed and fatigued. There was a problem.

In order to solve this problem, it is conceivable to delete the line-of-sight tracking AF / AE frame, but if the line-of-sight tracking AF / AE frame is always deleted, the AF
A new problem occurs in that the / AE area cannot be confirmed at all.

The present invention has been made under such a background, and its purpose is to reduce the fatigue of the photographer and
Eye-tracking AF / AE that can also check the F / AE area
It is to realize the function.

[0025]

To achieve the above object, the invention according to claim 1 has a visual axis detecting means, and automatic focusing control is performed in accordance with the movement of the gazing point detected by the visual axis detecting means. , And a camera with a line-of-sight detection function that moves in the AF / AE area for automatic exposure control.
Display control means is provided for displaying / erasing the AF / AE area frame indicating the E area on the finder screen in accordance with the operating environment.

In order to achieve the above object, in the invention according to claim 2, the display control means in claim 1 displays the AF / AE area frame only in a lock mode for locking the AF / AE area. Is configured.

To achieve the above object, in the invention according to claim 3, the display control means according to claim 1 sets the AF / AE area frame when a lock mode for locking the AF / AE area is set. Is displayed, and is erased after a predetermined time has elapsed.

To achieve the above object, in the invention according to claim 4, the display control means in claim 1 moves the AF / AE area in accordance with the movement of the gazing point detected by the line-of-sight detection means. The AF / AE area frame is displayed in the line-of-sight tracking mode, and is erased when the lock mode for locking the AF / AE area is set.

[0029]

According to the first aspect of the invention, the display control means displays / erases the AF / AE area frame indicating the AF / AE area on the finder screen in accordance with the operating environment, whereby the line-of-sight tracking AF / When performing the AE function, the fatigue of the photographer is reduced and the AF / AE area can be confirmed.

According to a second aspect of the present invention, the display control means in the first aspect displays the AF / AE area frame only in the lock mode for locking the AF / AE area, so that the eye-gaze tracking AF / AE is performed. In executing the function, the fatigue of the photographer is reduced and the AF / AE area can be confirmed.

According to a third aspect of the present invention, the display control means according to the first aspect displays the AF / AE area frame when a lock mode for locking the AF / AE area is set, and a predetermined time elapses. By deleting after that, the fatigue of the photographer is reduced and the AF / AE area can be confirmed when executing the line-of-sight tracking AF / AE function.

According to a fourth aspect of the present invention, the display control means in the first aspect is configured to move the AF in the line-of-sight tracking mode in which the AF / AE area is moved according to the movement of the gazing point detected by the line-of-sight detecting means. / AE area frame is displayed, and when the lock mode for locking the AF / AE area is set, the line tracking AF /
When performing the AE function, the fatigue of the photographer is reduced and the AF / AE area can be confirmed.

[0033]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A camera with a visual line inspection function according to an embodiment of the present invention will be described below with reference to the drawings. Since the principle of eye-gaze detection (see FIG. 5 and the like) and the constituent elements of the camera with eye-gaze inspection function (see FIG. 7) are the same as those in the conventional example, description thereof will be omitted and only different points will be described.

[First Embodiment] FIG. 1 shows a viewfinder display example of a video camera with a line-of-sight AF / AE function to which the first embodiment of the present invention is applied. AE area (no frame display), 3 for AF /
This is an AE area (with frame display: the frame displayed to show this area is referred to as an AF / AE area frame 3a).

Here, the AF / AE areas 2 and 3 are areas for detecting high-frequency components of the image signal, and a subject in this area can be focused, and AE is also performed at the same time. The AF / AE area frame 3a is displayed at the gazing point position, and the AF / AE areas 2 and 3 always move according to the movement of the line of sight.

FIG. 1A shows the finder display screen 1 in the normal line-of-sight tracking mode, in which AF / AE can be performed at the point of gaze, and in this mode, the AF / AE area frame 3a is displayed. Do not display in the viewfinder. In FIG. 1B, by pressing the line-of-sight AF / AE frame lock SW 710, the AF is performed at the point of interest at that time.
/ AE area is fixed, and in the AF / AE area lock mode, the display in the viewfinder of the AF / AE area frame 3a is performed.

The above operation will be described in detail with reference to the flowchart of FIG. 2. First, the system controller 708 sets a line-of-sight tracking mode for moving the AF / AE area in accordance with the movement of the line of sight (step S1). Next, it waits until the line-of-sight AF / AE frame lock SW 710 is turned on (step S2).

The line-of-sight AF / AE frame lock SW71
When 0 is turned on, the AF / AE area lock mode for locking the AF / AE area is set (step S
3), the AF / AE area frame 3a is displayed (step S
4). Next, the line-of-sight AF / AE lock SW 710 turns off again.
When the line-of-sight AF / AE lock SW 710 is turned on (step S5), the AF / AE area frame 3a is turned off (step S6), the process returns to step S1, and the line-of-sight tracking mode is set again. To do.

[Second Embodiment] FIG. 3 shows the finder display contents in the second embodiment of the present invention, in which 1 is a finder display screen and 2 is an AF / AE area (AF / A).
Reference numeral 3 denotes an AF / AE area (display of the AF / AE area frame 3a).

Here, the AF / AE areas 2 and 3 are areas for detecting high-frequency components of the image signal, and a subject in this area can be focused, and AE is also performed at the same time. The AF / AE area frame 3a is displayed at the gazing point position, and the AF / AE areas 2 and 3 always move according to the line of sight.

FIG. 3A shows a display state at the time of normal line-of-sight tracking, in which AF / AE can be performed at the point of gaze and, in this case, the AF / AE area frame 3a is not displayed in the finder. . FIG. 3B shows a display state immediately after pressing the line-of-sight AF / AE frame lock SW 710, and the AF / AE area is fixed at the gazing point coordinates at that time. At this time, the display in the finder of the AF / AE area frame 3a is performed. FIG. 3C shows a state after a certain time has elapsed after pressing the line-of-sight AF / AE frame lock SW 710,
The AF / AE area remains fixed, but at this time, the display in the viewfinder of the AF / AE area frame 3a is turned off.

The above operation will be described in detail with reference to the flowchart of FIG. 4. First, the system controller 708 sets a line-of-sight gaze tracking mode for moving the AF / AE area according to the movement of the line of sight (step S11). Next, it waits until the line-of-sight AF / AE frame lock SW 710 is turned on (step S12).

The line-of-sight AF / AE frame lock SW71
When 0 is turned on, the AF / AE area lock mode for locking the AF / AE area is set (step S1).
3), the AF / AE area frame 3a is displayed (step S
14). Next, the count value of the counter X inside the system controller 708 is incremented by "1" (step S15), and it is determined whether the count value of the counter X is 10 or more (step S16). If the count value is not 10 or more, step S15
By returning to step 1 and performing the increment process, the process waits until a predetermined time elapses.

When the count value becomes 10 or more and the predetermined time has elapsed, the AF / AE area frame 3a is erased (step S17), and the line-of-sight AF / AE lock SW 710 is again used.
It waits until is turned on (step S18). When the line-of-sight AF / AE lock SW 710 is turned on again, the process returns to step S1 and the line-of-sight tracking mode is set again.

The present invention is not limited to the above embodiment, and for example, the AF / AE area frame may be displayed in the eye-tracking mode and erased in the AF / AE area lock mode. The present invention can also be applied to still cameras other than video cameras. Furthermore, A
As long as it has an F lens, it can be applied to a camera having any type of lens group.

[0046]

As described above, according to the present invention,
The AF / AE area frame can be displayed on the viewfinder screen only in the lock mode for locking the AF / AE area for automatic focusing control and automatic exposure control, reducing the fatigue of the photographer, and It is possible to realize a line-of-sight tracking AF / AE function that can also confirm the AF / AE area.

[Brief description of drawings]

FIG. 1 is a diagram showing a viewfinder display example of a video camera with a line-of-sight AF function to which a first embodiment of the present invention is applied.

FIG. 2 is a flowchart showing AF / AE frame display processing according to the first embodiment of the present invention.

FIG. 3 is a diagram showing a finder display example according to a second embodiment of the present invention.

FIG. 4 is a flowchart showing AF / AE frame display processing according to the second embodiment of the present invention.

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

FIG. 6 is an explanatory diagram for explaining the principle of line-of-sight detection.

FIG. 7 is a schematic configuration diagram showing an example of a video camera with a line-of-sight function.

FIG. 8 is a diagram showing a viewfinder display example in a conventional video camera with a line-of-sight function.

[Explanation of symbols]

 1 ... Viewfinder display screen 2 ... AF / AE area (without frame display) 3 ... AF / AE area (with frame display) 3a ... AF / AE area frame 701 ... Lens imaging system 702 ... Viewfinder screen 703 ... Viewfinder 706 ... Attention point Detection unit 707 ... Display circuit 708 ... System controller 710 ... Line-of-sight AF / AE frame lock SW

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location H04N 5/765 H04N 5/91 L

Claims (4)

[Claims] 1. A camera with a line-of-sight detection function that moves the AF / AE area for automatic focusing control and automatic exposure control according to the movement of the gazing point detected by the line-of-sight detection means. 2. A camera with a line-of-sight detection function, further comprising display control means for displaying / erasing an AF / AE area frame indicating the AF / AE area on a finder screen according to an operating environment. 2. The display control means is configured to lock the AF / AE area only in the lock mode.
The camera with a visual axis detection function according to claim 1, wherein an area frame is displayed. 3. The display control means sets the A when the lock mode for locking the AF / AE area is set.
The camera with a visual axis detection function according to claim 1, wherein the F / AE area frame is displayed and is erased after a predetermined time has elapsed. 4. The AF / AE unit according to the movement of the gazing point detected by the line-of-sight detecting unit.
In the eye tracking mode for moving the area, the AF / AE
The camera with a visual axis detection function according to claim 1, wherein an area frame is displayed and is erased when a lock mode for locking the AF / AE area is set.