Viewing apparatus with visual axis detector

Claim 2

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.

Claim 3

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

Claim 4

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

Claim 5

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.

Claim 6

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.

Claim 7

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.

Claim 8

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.

Claim 9

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.

Claim 10

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.

Claim 11

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.

Claim 12

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.

Claim 13

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

Claim 14

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

Claim 15

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.

Claim 16

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.