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Method and apparatus for determining the distance between the surface of an eye and a reference point

Assignee: CLEGG JR GILES C
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Filing: 1973-12-28
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Granted: 1975-09-09
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Expires: 1993-12-28
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Abstract

Abstract The distance between the cornea of a human eye and some reference point is determined by projecting, from locations on either side of the reference point, a pair of light images toward the eye so that the pathways traversed by the projected light images intersect at some predetermined distance from the reference point. The desired distance between the eye and the reference point is determined when the person is positioned so that the projected images are superimposed on the cornea of the person''s eye. In accordance with one embodiment of the invention, when the desired distance is determined, moveable headrest apparatus which is in contact with the person''s forehead is locked in place to assist in preventing further movement of the person''s head.

Inventors

  • 👤 Jr George W Tate

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 23:30
CPC Classifications
A; A61; A61B; A61B3/00; A61B3/0083; A61B3/10; A61B3/13; A61B3/135

Claims Analysis

Total Claims: 14
Claim 1
Independent Claim 202 words
Apparatus for defining a distance between the surface of the eye of a person and a reference point comprising a frame on which said reference point is defined, first projecting means carried by said frame and positioned on one side of the reference point for projecting an image in a first direction generally toward the person''s eye, second projecting means carried by said frame and positioned on the other side of the reference point for projecting an image in a second direction generally toward the eye, said projectiNg means being positioned so that the projected images will be superimposed on each other on the surface of the eye when the eye is located at a predetermined distance from the reference point, a housing secured to said frame, movable headrest means extending from said housing for contacting the head of the person and movable with respect to the reference point, biasing means for urging the headrest towards the person and maintaining contact between headrest and the head of the person when the head is within a certain distance of the reference point and an indicating means for providing an indication of the position of said moveable headrest means relative to the reference point.
Claim 2
Dependent Claim 202 words
Apparatus for defining a distance between the surface of the eye of a person and a reference point comprising a frame on which said reference point is defined, first projecting means carried by said frame and positioned on one side of the reference point for projecting an image in a first direction generally toward the person''s eye, second projecting means carried by said frame and positioned on the other side of the reference point for projecting an image in a second direction generally toward the eye, said projectiNg means being positioned so that the projected images will be superimposed on each other on the surface of the eye when the eye is located at a predetermined distance from the reference point, a housing secured to said frame, movable headrest means extending from said housing for contacting the head of the person and movable with respect to the reference point, biasing means for urging the headrest towards the person and maintaining contact between headrest and the head of the person when the head is within a certain distance of the reference point and an indicating means for providing an indication of the position of said moveable headrest means relative to the reference point.
Claim 3
Dependent Claim 23 words
Apparatus as in claim 1 further comprising manual means for locking said movable means in a position fixed relative to the reference point.
Claim 4
Dependent Claim 30 words
Apparatus as in claim 1 wherein said indicating means comprises means for generating and electrical signal indication of the position of said movable headrest means relative to the reference point.
Claim 5
Dependent Claim 41 words
Apparatus as in claim 1 further comprising periscope means secured to said frame and positioned to enable a person to view therethrough the surface of said eye when the eye is located substantially at said predetermined distance from the reference point.
Claim 6
Dependent Claim 27 words
Apparatus as in claim 1 wherein said indicating means comprises indicia on said movable means for indicating the position of said headrest relative to said reference point.
Claim 7
Dependent Claim 99 words
Apparatus as in claim 1 including mounting means for rotatably mounting said first projection means and said second projection means on said frame for rotation about generally vertically disposed, parallel axis, means responsive to rotation of one of said projecting means for causing the other projecting means to rotate by a mount equal to but opposite in direction of the rotation of said one projecting means to cause the first and second light images to be superimposed on the cornea of the person''s eye at different pre-determined distances, means for indicating the rotational position of the first projecting means.
Claim 8
Dependent Claim 26 words
Apparatus as in claim 6 wherein said indicating means comprises a shaft angle Encoder for generating a signal indicating the rotation of said first projecting means.
Claim 9
Dependent Claim 65 words
Apparatus as in claim 1 wherein each of said projecting means comprises a light emitting means, a focusing lens for focusing the projected image at substantially said desired distance, and a transparent slide positioned between said light emitting means and said focusing means for carrying the image light from said light emitting means through said slide and said focusing means to project the light image.
Claim 10
Dependent Claim 35 words
Apparatus as in claim 8 wherein the image of the transparent slide associated with the first projecting means is different from but complimentary to the image of the transparent slide of the second projecting means.
Claim 11
Dependent Claim 170 words
Apparatus for fixing the distance between the cornea of the eye of a person and a reference point on refraction equipment comprising means secured to said refraction equipment on one side of the reference point for projecting a first light image along a first pathway generally toward the person, means secured to said equipment on the other side of said reference point for projecting a second light image along a second pathway generally toward the person, said first and second pathways intersecting a predetermined distance from the reference point, the desired distance between the cornea of the eye and the reference point being established when the first light image is superimposed over the second light image on the cornea of the eye, a headrest feeler means for contacting the persons forehead when the eye of the person is positioned at said desired distance from said reference point, and means responsive to movement of said feeler means for generating an electrical signal to thereby indicate that the persons forehead has moved.
Claim 12
Dependent Claim 170 words
Apparatus for fixing the distance between the cornea of the eye of a person and a reference point on refraction equipment comprising means secured to said refraction equipment on one side of the reference point for projecting a first light image along a first pathway generally toward the person, means secured to said equipment on the other side of said reference point for projecting a second light image along a second pathway generally toward the person, said first and second pathways intersecting a predetermined distance from the reference point, the desired distance between the cornea of the eye and the reference point being established when the first light image is superimposed over the second light image on the cornea of the eye, a headrest feeler means for contacting the persons forehead when the eye of the person is positioned at said desired distance from said reference point, and means responsive to movement of said feeler means for generating an electrical signal to thereby indicate that the persons forehead has moved.
Claim 13
Dependent Claim 65 words
Apparatus as in claim 10 wherein said projecting means each comprise a light emitting means, a focusing lens for focusing the projected image at substantially said desired distance, and a transparent slide positioned between said light emitting means and said focusing lens for carrying the image light from said light emitting means passing through said slide and said focusing lens to project the light image.
Claim 14
Dependent Claim 26 words
Apparatus as in claim 10 wherein said signal generating means includes means for generating a signal indicating the magnitude of the movement of said feeler means.

References Cited (Backward Citations)

US1651661A Cited
US2081969A Cited
US3002093A Cited
US3187185A Cited
US3408137A Cited
US3817631A Cited
US3622242A Cited
US3610128A Cited
US3807858A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1978-09-08 1979-03-10 1979-09-09 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1982-09-08 1983-03-10 1983-09-09 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1986-09-08 1987-03-10 1987-09-09 $7700.00 Window Closed / Lapsed

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