Viewing apparatus with visual axis detector

• US 5,712,684 A
• Filed: 04/03/1996
• Issued: 01/27/1998
• Est. Priority Date: 04/16/1993
• Status: Expired due to Term

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Takahashi, Hidekazu, Inoue, Shunsuke
• Primary Examiner(s): GARBER, WENDY RAE
• Application Number:
  US08/624,201
• Time in Patent Office: 664 Days
• Field of Search: 348/341, 348/345, 348/335, 348/333, 354/400, 354/62
• US Class Current: 348/341
• CPC Class Codes: G02B 27/02 Viewing or reading apparatus stereoscopic systems G02B30/00
• CPC Class Codes: G03B 13/02 Viewfinders
• CPC Class Codes: G03B 2213/025 Sightline detection

Abstract

A viewing apparatus exhibiting high performance and an image forming apparatus including the same. The viewing apparatus includes a projection optical system for projecting an image on a viewer'"'"'s eye, a detector for detecting the refractive power of the viewer'"'"'s eye, and an adjustor for adjusting the projection optical system so that the image is formed substantially on a viewer'"'"'s eye fundus. The imaging apparatus includes an imager for forming an image of an object, a projection optical system for projecting the object image on the viewer'"'"'s eye, a detector for detecting the refractive power of the viewer'"'"'s eye, and an adjustor for adjusting the projection optical system so that the object image is formed substantially on the viewer'"'"'s eye fundus in accordance with the refractive power of the viewer'"'"'s eye.

Claims

1. An observing apparatus having a projecting optical system for projecting an object image onto an eye of an observer, comprising:

image detecting means for receiving a first reflection light from a fundus of the eye;

controlling means for detecting the refracting power of the eye based on an output of said image detecting means, said controlling means including adjusting means for adjusting said observing apparatus so that the object image is substantially focused on the fundus of the eye based on a result of detection of the refracting power of the eye,

wherein said image detecting means is disposed at a position in optical conjugation with a pupil of the eye such that a first image is formed in front of said image detecting means by the first reflection light from the eye fundus and a second image is formed on said image detecting means by a second reflection light from the pupil of the eye and from the neighborhood of the pupil;

wherein said observing apparatus changes the distribution of the intensity of light on said image detecting means due to the first and second reflection light according to the refracting power of the eye and the direction of the visual axis of the eye; and

wherein said controlling means detects both the refracting power of the eye and the direction of the visual axis of the eye based on the distribution of the intensity of light represented by the output of said image detecting means.

2. An apparatus according to claim 1, wherein said adjusting means has means for moving the projection optical system in an optical-axis direction.

3. An apparatus according to claim 1, wherein the projecting optical system has an optical system of a variable focal length.

4. An apparatus according to claim 1, wherein said controlling means first adjusts said observing apparatus so that the refracting power of the eye is detected based on the first image and the object image is substantially focused on the fundus of the eye based on a result of detection of the refracting power of the eye and, second detects the direction of the visual axis of the eye of the observer based on the second image.

5. An apparatus according to claim 1, wherein said apparatus has an infrared light source for emitting an illumination light for illuminating the eye in order to form the first and second reflection light.

6. An image forming apparatus comprising:

an observing apparatus comprising;

a projecting optical system for projecting an object image onto an eye of an observer;

image detecting means for receiving a first reflection light from a fundus of the eye; and

controlling means for detecting the refracting power of the eye based on an output of said image detecting means, said controlling means including adjusting means for adjusting said observing apparatus so that the object image is substantially focused on the fundus of the eye based on a result of detection of the refracting power of the eye,

wherein said image detecting means is disposed at a position in optical conjugation with a pupil of the eye such that a first image is formed in front of said image detecting means by the first reflection light from the eye fundus and a second image is formed on said image detecting means by a second reflection light from the pupil of the eye and the neighborhood of the pupil;

wherein said observing apparatus changes the distribution of the intensity of light on said image detecting means due to said first and second reflection light according to the refracting power of the eye and the direction of the visual axis of the eye;

wherein said controlling means detects both the refracting power of the eye and the direction of the visual axis of the eye based on the distribution of the intensity of light represented by the output of said image detecting means; and

an image forming device having image forming means for forming the object image.

7. An image forming apparatus according to claim 6, further comprising means for adjusting said image forming device in response to a signal from said controlling means representing the detected visual axis of the eye.

8. An image forming apparatus according to claim 7, wherein said adjusting means has means for moving at least one phototaking lens element of said image forming device.

9. An apparatus according to claim 7, further comprising a substrate in which are formed a liquid crystal display device for displaying the object image projected by said projecting optical system and a member for converting the first and second images into electrical signals.

10. An image forming apparatus according to claim 6, further comprising a focusing plate, wherein said projection optical system projects the object image on said focusing plate again on the eye of the observer.

11. An apparatus according to claim 6, wherein said adjusting means has means for moving said projection optical system in an optical-axis direction.

12. An apparatus according to claim 6, wherein said projecting optical system has a variable focal length optical system.

13. An apparatus according to claim 6, wherein said controlling means first adjusts said observing apparatus so that the refracting power of the eye is detected based on the first image and the object image is substantially focused on the fundus of the eye based on a result of detection of the refracting power of the eye and, second detects the direction of the visual axis of the eye of the observer based on the second image.

14. An apparatus according to claim 6, wherein said apparatus has an infrared light source for emitting an illumination light for illuminating the eye in order to form the first and second reflection light.