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US4252420A Expired / Lapsed US ⏱️ 0.0 years remaining

Ophthalmoscopical apparatus provided with adjustment system

Assignee: Canon Inc
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Filing: 1978-04-10
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Granted: 1981-02-24
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Expires: 1998-04-10
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Abstract

Abstract An ophthalmoscopical apparatus for carrying out aligning and/or spacing an eye examining instrument is disclosed. The apparatus includes a projection optical system disposed obliquely to the optical axis of the objective lens of the instrument. A beam of infrared light is projected from the projection optical system so as to form an image of indication at a position spaced from the objective lens by a predetermined distance. A beam reflected upon the anterior part of the subject eye is incident on the objective lens and focused on the light receiving surface of an image pick-up tube through an image transmitting system. Thus, an image of the reflected beam is displayed on a screen of cathode ray tube. The examiner adjusts the position of the instrument while observing the image on the cathode ray tube. The adjustment is made in the directions of up-and-down, left-and-right and for-and-back until the image of reflection on the cathode ray tube comes in a predetermined position.

Inventors

  • 👤 Yoshimi Kohayakawa

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-30 14:35
CPC Classifications
A; A61; A61B; A61B3/00; A61B3/10; A61B3/13

Claims Analysis

Total Claims: 12
Claim 1
Independent Claim 168 words
An ophthalmoscopical apparatus provided with an adjustment system, said apparatus comprising: an eye inspecting system including front optical means adapted to be disposed opposite to the eye to be examined; a beam transmitting system coupled with said eye inspecting system through beam-direction selecting means; an observing device coupled with said beam transmitting system for optically observing the anterior part of the eye to be examined; and a projection device comprising means for supporting a chart and optical means for projecting the image of a chart supported by said supporting means onto an eye surface which is spaced a predetermined distance from said front optical means, the optical axis of said projection device being inclined at a predetermined angle with respect to the optical axis of the eye inspection system said chart supporting means being positioned in said apparatus to support a chart such that the image of said chart appears in a predetermined location on said eye when the distance between said eye and said apparatus is correct.
Claim 2
Dependent Claim 168 words
An ophthalmoscopical apparatus provided with an adjustment system, said apparatus comprising: an eye inspecting system including front optical means adapted to be disposed opposite to the eye to be examined; a beam transmitting system coupled with said eye inspecting system through beam-direction selecting means; an observing device coupled with said beam transmitting system for optically observing the anterior part of the eye to be examined; and a projection device comprising means for supporting a chart and optical means for projecting the image of a chart supported by said supporting means onto an eye surface which is spaced a predetermined distance from said front optical means, the optical axis of said projection device being inclined at a predetermined angle with respect to the optical axis of the eye inspection system said chart supporting means being positioned in said apparatus to support a chart such that the image of said chart appears in a predetermined location on said eye when the distance between said eye and said apparatus is correct.
Claim 3
Dependent Claim 50 words
An ophthalmoscopical apparatus according to claim 1, wherein said eye inspecting system comprises rear lens means disposed behind said front optical means, a photographic film disposed behind said rear lens means and an image transmitting system for transmitting the beam emerging from said rear lens means to said observing device.
Claim 4
Dependent Claim 42 words
An ophthalmoscopical apparatus according to claim 1, wherein said eye inspecting system includes rear lens means disposed behind said front optical means and said beam transmitting system includes a beam reflector interposed between said front optical means and said rear lens means.
Claim 5
Dependent Claim 71 words
An ophthalmoscopical apparatus according to claim 1, wherein said eye inspecting system comprises rear lens means disposed behind said front optical means, a photographic film disposed behind said rear lens means and an image transmitting system for transmitting the beam emerging from said rear lens means to said observing device, and said beam transmitting system includes convergent lens means removably interposed between said front optical means and said rear lens means.
Claim 6
Dependent Claim 27 words
An apparatus according to claim 1, wherein said eye inspecting system is optically connected with said observing device, and said beam-direction selecting means includes a beam splitter.
Claim 7
Dependent Claim 15 words
An apparatus according to claim 5, wherein said beam splitter includes a partially reflecting mirror.
Claim 8
Dependent Claim 173 words
An ophthalmoscopical apparatus provided with an adjustment system, said apparatus comprising: a photographic system including objective lens means, a photographic film and an observing device; a beam transmitting system adapted for transmitting a beam from said objective lens means to a light receiving surface of said observing device and also for bringing the anterior part of the eye to be examined and said light receiving surface together with said objective lens means into a substantially conjugated relation; a projection device comprising means for supporting at least one indication device and optical means for projecting the image of the indication on an eye surface which is spaced a predetermined distance from said objective lens means; and means for supporting a chart across the optical path of said beam transmitting system to allow the image of the indication to be checked; said indication device being so positioned in said apparatus that the image of said indication appears in a predetermined location on said eye when the distance between said eye and said apparatus is correct.
Claim 9
Dependent Claim 173 words
An ophthalmoscopical apparatus provided with an adjustment system, said apparatus comprising: a photographic system including objective lens means, a photographic film and an observing device; a beam transmitting system adapted for transmitting a beam from said objective lens means to a light receiving surface of said observing device and also for bringing the anterior part of the eye to be examined and said light receiving surface together with said objective lens means into a substantially conjugated relation; a projection device comprising means for supporting at least one indication device and optical means for projecting the image of the indication on an eye surface which is spaced a predetermined distance from said objective lens means; and means for supporting a chart across the optical path of said beam transmitting system to allow the image of the indication to be checked; said indication device being so positioned in said apparatus that the image of said indication appears in a predetermined location on said eye when the distance between said eye and said apparatus is correct.
Claim 10
Dependent Claim 32 words
An ophthalmoscopical apparatus according to claim 7, wherein the beam emerging from said indication is of infrared light and said observing device comprises an image pick-up means and an image display device.
Claim 11
Dependent Claim 35 words
An ophthalmoscopical apparatus a-cording to claim 7, wherein said beam transmitting system comprises a swing movable reflector adapted in one position to be disposed directly behing said objective lens means and a relay lens means.
Claim 12
Dependent Claim 25 words
An ophthalmoscopical apparatus according to claim 7, wherein said beam transmitting system includes a convergent lens means removably disposed directly behind said objective lens means.

References Cited (Backward Citations)

US3871772A Cited
US3904280A Cited
US4102563A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1984-02-24 1984-08-25 1985-02-24 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1988-02-24 1988-08-25 1989-02-24 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1992-02-24 1992-08-25 1993-02-24 $7700.00 Window Closed / Lapsed

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