JPH09211309A - Camera provided with line-of-sight detection means - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily and precisely detect line-of-sight information while the whole of a device is simplified by reflecting the image information of an eyeball on a mirror for bending an optical path after transmitting it through an eyepiece and a reflection member, forming it on the surface of a photodetector by using an image forming lens and obtaining the line-of-sight information of the eyeball. SOLUTION: When a release button is half-depressed by a photographer (finder observer), infrared light is projected toward the eyeball 102 of the photographer by an infrared light emitting diode (IRED) 5. The infrared light reflected from the eyeball 102 is transmitted through the eyepiece 4 whose both surfaces are applied with antireflection coating and the emitting surface 3c and the inclined reflection surface 3e of a pentagonal prism 3 in turn and emitted outside from the prism 3. Then, it is bent to a photographing optical axis 103 side by the mirror 6 so as to form an eyeball image on a sensor for detecting the line of sight 9 through the diaphragm 7 of a line-of-sight detection optical system and a condensing lens for detecting the light of sight 8. Based on a signal outputted from the sensor 9, the line-of-sight position of the eyeball 102 of the photographer is detected.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a camera having line-of-sight detecting means, and more particularly, the line-of-sight detecting means detects the line-of-sight direction of a photographer looking into the field of view of the finder to obtain a gaze direction and a point of gaze within the field of view of the finder. In addition, various photographing operations based on a signal obtained by the line-of-sight detection means, for example, a photographic camera and a video camera, in which focus detection is performed by focus detection means having a function of detecting in-focus states in a plurality of regions of a subject , SV cameras and the like.

[0002]

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

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

In Japanese Patent Laid-Open No. 3-171122, infrared light from a light source means provided in a part of a viewfinder system of a single-lens reflex camera is guided onto a viewfinder optical axis by using a dichroic mirror, and the infrared light is emitted. Is projected to the eyeball of the photographer who observes the viewfinder field, and infrared reflected light from the cornea of the eyeball is guided to the outside of the pentaprism through the eyepiece lens and the inclined reflection surface of the pentaprism to detect the line of sight. There has been proposed a camera having a visual line detection means configured to guide the sensor to detect visual line information.

[0005]

As an eye-gaze detecting method for detecting eye-gaze information of an eye-ball of an observer who looks into a focusing screen (finder field) in which a subject image is formed by a photographing system in a single-lens reflex camera, The method of detecting the reflected light from the eyepiece and the exit surface of the pentaprism for erecting the viewfinder image and the inclined reflecting surface to let it out of the pentaprism, and then guiding it to the light receiving element for detection is comparatively The feature is that the line-of-sight information can be obtained with a simple configuration. However, the method of detecting the line-of-sight information by guiding the reflected light from the eyeball from the exit surface of the pentaprism, emitting it through the inclined reflecting surface of the pentaprism, and then guiding it to the light receiving element is Since the outer shape is a shape that protrudes to the front of the camera and above the camera,
Each element for gaze detection will be placed around it,
There was a problem that the entire camera became larger.

Particularly, a method of guiding the reflected light from the eyeball that has passed through the inclined reflection surface (final reflection surface) of the pentaprism to a visual axis detection system provided above the camera and detecting it is provided above the pentaprism. The problem arises that it mechanically interferes with the built-in flash.

In order to avoid mechanical interference at this time, it is difficult to obtain a bright eyeball image if the elements for detecting the line of sight are arranged apart from the pentaprism to some extent, and the peripheral portion of the pentaprism becomes large. Problem arises.

The present invention illuminates the eyeball of an observer looking into the field of view of the finder with infrared light, and guides the infrared reflected light from the eyeball to the light receiving element through a part of the optical member for erecting the finder image. However, when detecting the line-of-sight information using the eyeball image information obtained by the light-receiving element, the line-of-sight information of the entire device by appropriately configuring each element such as the optical member for the finder image erecting and the detection system. An object of the present invention is to provide a camera having a line-of-sight detecting means that is capable of detecting with high accuracy, easily and with high precision while performing simplification.

[0009]

A camera having a line-of-sight detecting means of the present invention comprises: (1-1) A light beam from a subject that has passed through a photographing system is moved upward from a photographing optical path through a mirror that is removable. When the object image on the focusing plate is reflected and observed with an eyepiece through an optical member for forming an erect image having a roof mirror and a reflecting member having a light splitting action, the eyepiece The eyeball of the observer looking through the lens is illuminated with a light flux from the light source means, and eyeball image information based on the reflected light from the eyeball is passed through the eyepiece lens and the reflecting member, and then the optical path bending mirror is used to It is characterized in that a line-of-sight detecting means for reflecting the light in the optical axis direction and forming it on the surface of the light-receiving element by the imaging lens and for obtaining the line-of-sight information of the eyeball by using the output signal from the light-receiving element is provided.

In particular, (1-1-1) the light source means has a light source for emitting infrared light, and the eyepiece lens is provided with an infrared light antireflection film, (1-1- 2) The optical member is composed of a penta prism, (1-1-
3) The optical path bending mirror, the imaging lens, and the light receiving element are arranged in a space formed by the extension surface of the focusing plate and the inclined reflecting surface of the pentaprism.
1-4) The reflection member is an inclined reflection surface of the pentaprism, and (1-1-5) the inclined reflection surface is a dichroic reflection surface that reflects visible light and transmits infrared light.
(1-1-6) The roof mirror is formed of a hollow roof mirror, and the reflection member is formed of a plane parallel plate including an inclined reflection surface inclined with respect to the optical axis of the eyepiece lens. 1-7) The inclined reflection surface is a dichroic reflection surface that reflects visible light and transmits infrared light, (1-1
-8) The light source means is a plurality of infrared light emitting diodes, and the plurality of light emitting diodes are provided in the peripheral portion of the eyepiece lens. (1-1-9) From the line-of-sight detection means It is characterized in that an automatic focus detection means for detecting the focus of the photographing system is provided in a predetermined area in the finder field based on the line-of-sight information.

[0011]

1 is a schematic view of a main part of a first embodiment when the present invention is applied to a single-lens reflex camera, and FIG. 2 is an enlarged perspective view of a part of FIG.

In the figure, 101 is a camera body of a single-lens reflex camera. Reference numeral 100 denotes a mount for interchangeably mounting a photographing lens (not shown) on the camera body 101, and 1 is a flip-up mirror, which is retracted from the optical path when a subject image is exposed on the film (photosensitive surface) 12. In other cases, the subject light from the taking lens is guided to the focusing screen 2 of the finder system. A part of the flip-up mirror 1 is a half mirror surface. Reference numeral 2 denotes a focusing screen (screen) on which a subject image formed by the taking lens is formed via the mirror 1. Reference numeral 3 is an optical member for erecting the finder image. The optical member 3 is composed of a solid penta prism as shown in FIG.

Next, referring to FIG. 2, the surface definition of the pentaprism 3 will be described. The 3a surface of the pentaprism 3 is formed by an angle of 90 ° formed by the two reflecting surfaces 3a1 and 3a2. The roof surface (roof mirror surface), 3b (3b1 and 3b2) surfaces are left and right side walls, and 3c surface is finder light emission. The surface of the eyeball 102 of the infrared light emitted from the light source means 5 described later.
It becomes the incident surface of the infrared light reflected from, and in this embodiment, an antireflection coating is applied. The surface 3d is a non-functional surface, and the surface 3e is an inclined reflecting surface for aligning the optical axis fa of the eyepiece lens 4 and the optical axis 103 of the photographing lens.
The infrared light reflected from 02 is transmitted. That is, it is composed of a dichroic mirror that reflects visible light and transmits infrared light. 3f
The surface is an incident surface of the light flux from the finder image on the focusing screen 2.

Reference numeral 4 denotes an eyepiece lens, both sides of which antireflection films are applied. Reference numeral 5 is a light source unit that emits infrared light, and includes a plurality of light emitting diodes (IRED) 5a, 5
b, 5c, 5d, which are arranged around the eyepiece 4. The light source means 5 illuminates the eyeball 102 of the observer who observes the viewfinder field so that the light reflected by the center of the observer's pupil and the surface of the cornea (Purkinje image) can be detected by the light receiving element 9 described later.

Reference numeral 6 denotes a mirror (optical path bending mirror), which reflects infrared reflected light from the eyeball 102 that has passed through the inclined reflecting surface 3e to the lower side of the camera body 101. Reference numeral 7 is a diaphragm, 8 is a condenser lens, and 9 is a light receiving element. Each of these elements 5, 6, 7, 8 and 9 constitutes one element of the visual axis detecting means.

In this embodiment, each element 6, 7 for detecting the line of sight is provided in the space formed by the extension surface of the focusing screen 2 and the inclined reflecting surface 3e.
By arranging 8, 9, etc., the space in the vicinity of the pentaprism 3 is effectively utilized, and the size of the entire apparatus is reduced.

Reference numeral 10 denotes a sub-mirror, which is fixed to the mirror 1 and guides the light flux from the photographing lens that has passed through the light transmission region (half mirror surface) of the mirror 1 to the automatic focus detection device (AF device). doing. The AF device 11 detects the in-focus state of the photographing lens by a known detection method for a single or a plurality of distance measuring areas based on the line-of-sight information from the line-of-sight detecting means.

Reference numeral 13 is a strobe Xe tube built in the camera body 101, 14 is a strobe reflector, 15 is a front panel of the strobe, and 16 is a hinge shaft of the built-in strobe. Reference numeral 17 is an accessory shoe that is installed on the top of the camera body 101 and to which an external strobe can be attached.

In FIG. 1, a light flux from a subject that has passed through a taking lens (not shown) is reflected by a flip-up mirror 1 to form a subject image on the focal plane of a focusing plate 2. The light flux related to the subject image formed on the focusing plate 2 is reflected by the roof surface 3a and the inclined reflection surface 3e of the pentaprism 3, and the exit surface 3
c, the light enters the eyeball 102 of the photographer through the eyepiece lens 4. Thereby, the observer observes the subject image (finder image) formed on the focusing plate 2.

On the other hand, of the light flux from the subject, the light flux that has passed through part of the flip-up mirror 1 is incident on the AF device 11 via the sub-mirror 10. At this time, the focus state of the photographing lens in the distance measuring area based on the line-of-sight information from the line-of-sight detecting means is detected.

On the other hand, in the above arrangement, when the photographer (viewfinder observer) half-presses the release button (not shown),
The infrared light emitting diode (IRED) 5 projects infrared light to the eyeball 102 of the photographer. Infrared reflected light from the eyeball 102 is provided with an eyepiece lens 4 having antireflection coating on both sides in this order, the exit surface 3c of the pentaprism 3 and the inclined reflecting surface 3.
After passing through e, the light exits from the penta prism 3. Then, it is bent toward the photographing optical axis 103 side (downward) by the mirror 6, and an eyeball image is formed on the line-of-sight detection sensor 9 through the stop 7 of the line-of-sight detection optical system and the focusing lens 8 for line-of-sight detection. ing. The line-of-sight position (line-of-sight information) of the eyeball 102 of the photographer is detected based on the output signal from the line-of-sight detection sensor 9.

Then, the focusing device of the photographing lens is driven by the AF device 11 so that the subject image at the visual line position in the finder field based on the visual line information is in focus. When the photographer presses the release button fully,
The mirror 1 retracts from the photographing light flux, and the sub mirror 10 also retracts from the photographing light flux in conjunction with the mirror 1. And mirror 1
When is retracted from the photographing light flux, the shutter curtain (not shown) is controlled to expose the film 12. Note that in the present embodiment, a photographing operation other than AF, such as automatic exposure, may be performed using the line-of-sight information.

FIG. 3 is a schematic view of the essential portions of Embodiment 2 of the present invention,
FIG. 4 is an enlarged perspective view of a part of FIG.

This embodiment is different from the first embodiment shown in FIG.
As an optical member 31 for forming an erect image of a finder image formed on the focusing screen 2, instead of the solid pentaprism 3, a reflecting member 18 including a hollow roof mirror 31 and a plane parallel plate having an inclined reflecting surface 18a, and light emission. The difference is that it is configured by a parallel plane plate 31a for use in, and other configurations and operations are the same.

Next, the structure of the optical member 31 of this embodiment will be described.

The optical member 31 reflects the light from the finder image on the screen 2 and reflects the light reflected from the roof mirror 31b and the roof mirror 31b, which is composed of two reflecting members 31b1 and 31b2 that convert the light beams to the left and right. A reflecting member 18 having an inclined reflecting surface (effective reflecting surface) 18a which is a final reflecting surface tilted with respect to the finder optical axis fa for reflecting in the finder observation direction, and a transparent member provided with an antireflection film for emitting light. It has a plane parallel plate 31a.

The inclined reflecting surface 18a is a dichroic surface that reflects visible light and transmits infrared light. The reflection member 18 is attached to the front opening of the optical member 31. In this embodiment, the roof mirror 31b and the reflection member 18 are separately configured, and the dichroic film can be vapor-deposited on the inclined reflection surface 18a alone.

[0028]

As described above, according to the present invention, the eyeball of the observer looking into the viewfinder field is illuminated with infrared light, and the infrared reflected light from the eyeball is one of the optical members for erecting the viewfinder image. When detecting the line-of-sight information using the eyeball image information obtained by the light-receiving element by guiding the light to the light-receiving element through the section, each element such as the optical member for erecting the finder image and the detection system is appropriately configured. By doing so, it is possible to achieve a camera having a line-of-sight detecting means that detects the line-of-sight information easily and with high accuracy while simplifying the entire apparatus, thereby performing various shooting operations.

In addition to the above, according to the present invention, (b1) the inclined reflecting surface or the reflecting member 18 of the penta prism.
Since the mirror 6 reflects the reflected light that has passed through the inclined reflecting surface 18a toward the photographing optical axis (downward) to form an image on the light receiving element 9, the inclined reflecting surface of the pentaprism or the reflecting member is inclined. It becomes easy to arrange the built-in strobe in front of the reflecting surface. Also, the roof surface of the pentaprism, the apex of the inclined reflecting surface, the hollow roof mirror, or the reflecting member 1
Since another optical system can be arranged in the vicinity of the protrusion of 8 without worrying about it, the eyepiece lens and the mirror 6
The distance between and can be set short, the optical system is bright, and the accuracy can be increased.

(B2) When the reflected light from the eyeball is received by the light-receiving element for detecting the line of sight, antireflection coating is applied not only to both surfaces of the eyepiece but also to the surfaces of other optical elements to reduce the light amount or ghost. It is possible to obtain the effects of preventing the occurrence of the above-mentioned problem and realizing a highly accurate visual line detection device.

[Brief description of drawings]

FIG. 1 is a sectional view of an essential part of a first embodiment of the present invention.

FIG. 2 is an enlarged explanatory view of a part of FIG. 1;

FIG. 3 is a sectional view of an essential part of a second embodiment of the present invention.

FIG. 4 is an enlarged explanatory view of a part of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Mirror 2 Screen (focusing plate) 3,31 Optical member for erecting a viewfinder image 31a Parallel plane plate 31b Roof mirror 4 Eyepiece 5 IRED 6 Mirror 7 Eye-gaze detecting diaphragm 8 Eye-gaze detecting lens 9 Eye-gaze detecting sensor 10 Sub-mirror 11 AF Device 12 Film 13 Xe Tube 14 Reflective Umbrella 15 Front Panel 16 Hinge Axis 17 Accessory Shoe 3e, 18a Inclined Reflective Surface 100 Mount 101 Camera Body 102 Eyeball 103 Shooting Optical Axis fa Finder Optical Axis

Claims (10)

[Claims] 1. A light flux from a subject that has passed through a photographing system is reflected upward through a mirror that can be inserted into and removed from a photographing optical path and is formed on a focus plate, and a subject image on the focus plate is used as a roof mirror. When observing with an eyepiece through an optical member for forming an erect image having a reflecting member having a light splitting action, the eyeball of an observer looking into the eyepiece is illuminated with a light beam from a light source means, After the eyeball image information based on the reflected light is passed through the eyepiece lens and the reflecting member, it is reflected by the optical path bending mirror in the optical axis direction of the photographing system and formed on the light receiving element surface by the imaging lens, A camera having a line-of-sight detection unit, which is provided with a line-of-sight detection unit that obtains line-of-sight information of the eyeball by using an output signal from an element. 2. The line-of-sight detection means according to claim 1, wherein the light source means has a light source that emits infrared light, and the eyepiece lens is provided with an infrared light antireflection film. The camera that did. 3. A camera having line-of-sight detection means according to claim 1, wherein the optical member is composed of a penta prism. 4. The optical path bending mirror, the imaging lens, and the light receiving element are arranged in a space defined by an extension surface of the focusing plate and an inclined reflection surface of the pentaprism. A camera having a line-of-sight detection means. 5. A camera having line-of-sight detection means according to claim 3, wherein the reflecting member is an inclined reflecting surface of the pentaprism. 6. The camera with line-of-sight detection means according to claim 5, wherein the inclined reflection surface is a dichroic reflection surface that reflects visible light and transmits infrared light. 7. The roof mirror is formed of a hollow roof mirror, and the reflecting member is formed of a plane parallel plate including an inclined reflecting surface inclined with respect to the optical axis of the eyepiece lens. A camera having a line-of-sight detection means. 8. The camera with line-of-sight detection means according to claim 7, wherein the inclined reflecting surface is a dichroic reflecting surface that reflects visible light and transmits infrared light. 9. The light source means is a plurality of light emitting diodes for emitting infrared light, and the plurality of light emitting diodes are provided in a peripheral portion of the eyepiece lens.
A camera having the line-of-sight detection means of any one of 1 to 8. 10. The automatic focus detection means for detecting the focus of the photographing system is provided in a predetermined area within a viewfinder field based on the visual line information from the visual line detection means. A camera having the line-of-sight detection means described in any one of items.