Patent US3881812A successfully refreshed from Google Patents.
US3881812A
Expired / Lapsed
US
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Manually held indirect ophthalmoscope especially adapted for viewing the periphery of the fundus oculi
Assignee: BEN TOVIM NATHAN
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Filing: 1972-03-13
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Granted: 1975-05-06
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Expires: 1992-03-13
Abstract
Abstract The invention relates to a hand-instrument serving the purpose of direct and indirect ophthalmoscopy. One part of the instrument, which may be used alone, is a direct ophthalmoscope; it comprises - in contradistinction to known instruments of this kind - a reflecting means, such as a mirror or a prism which is vertically movable. The other part is an attachment for indirect ophthalmoscopy.
Inventors
- 👤 Nathan Ben-Tovim
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 09:18
CPC Classifications
A; A61; A61B; A61B3/00; A61B3/10; A61B3/12
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
221 words
An indirect ophthalmoscope comprising: a tubular portion to be held in the physician''s hand containing a light source for projecting a beam of light; a head portion attached to said tubular portion containing an observation hole through which the eye of the patient is examined and a movable reflecting means for reflecting the light beam from the light source into the eye of the patient being examined, the path of movement of said reflecting means being constrained to a rectilinear path perpendicular to the line of sight of the physician to the eye of the patient, said movement not affecting the direction and angular inclination of the projected light rays which remain parallel to the line of sight; an attachment means secured at one end to said tubular portion, the opposite end being free for resting on the face of the patient to be examined; a track disposed upon said attachment means; a convex lens disposed in said line of sight for viewing the fundus of the examined eye, said convex lens being movable on said track along the long of sight; and, mirror means positioned between the free end portion of said attachment means and said convex lens for receiving the reflected light from the periphery of the fundus and for transmitting said reflected light along said line of sight.
Claim 2
Dependent Claim
221 words
An indirect ophthalmoscope comprising: a tubular portion to be held in the physician''s hand containing a light source for projecting a beam of light; a head portion attached to said tubular portion containing an observation hole through which the eye of the patient is examined and a movable reflecting means for reflecting the light beam from the light source into the eye of the patient being examined, the path of movement of said reflecting means being constrained to a rectilinear path perpendicular to the line of sight of the physician to the eye of the patient, said movement not affecting the direction and angular inclination of the projected light rays which remain parallel to the line of sight; an attachment means secured at one end to said tubular portion, the opposite end being free for resting on the face of the patient to be examined; a track disposed upon said attachment means; a convex lens disposed in said line of sight for viewing the fundus of the examined eye, said convex lens being movable on said track along the long of sight; and, mirror means positioned between the free end portion of said attachment means and said convex lens for receiving the reflected light from the periphery of the fundus and for transmitting said reflected light along said line of sight.
Claim 3
Dependent Claim
42 words
An ophthalmoscope according to claim 1, wherein said attachment means contains a lens holder, positioned between said tubular portion and said means for examining the periphery of the eye, having a plurality of convex lenses selectively positionable in said line of sight.
Claim 4
Dependent Claim
25 words
An ophthalmoscope according to claim 1, wherein said attachment means contains a fixation target positioned under the means for examining the periphery of the eye.
Claim 5
Dependent Claim
17 words
An ophthalmoscope according to claim 3, wherein said fixation target is movable to a plurality of positions.
Claim 6
Dependent Claim
20 words
An ophthalmoscope according to claim 1, wherein said means for examining the periphery of the fundus comprises two plane mirrors.
Claim 7
Dependent Claim
29 words
An ophthalmoscope according to claim 5, wherein one of said plane mirrors is movably mounted so that its inclination may be varied with respect to the other plane mirror.
Claim 8
Dependent Claim
91 words
An ophthalmoscope according to claim 1, wherein said attachment means further carries a teleperiscopic unit enabling the observer to see the whole of the examined eye and its surroundings, said teleperiscopic unit comprising a semi-transparent mirror affixed to said extension between the examined eye and said convex lens, a plane mirror affixed to said fundus examining means, and a telescope, the ocular of which being adjacent to said observation hole, said transparent mirror reflecting the eye image to the plane mirror, said plane mirror reflecting the eye image to said telescope.
Claim 9
Dependent Claim
64 words
An ophthalmoscope according to claim 1, for enabling the fundus of the eye to be examined by an assistant or observer, wherein said attachment means carries a semi-transparent mirror disposed in said line of sight between the said head portion and said convex lens and oriented to reflect the said fundus image of the examined eye to the eye of the assistant or observer.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-05-05 | 1978-11-04 | 1979-05-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-05-05 | 1982-11-04 | 1983-05-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-05-05 | 1986-11-04 | 1987-05-06 | $7700.00 | Window Closed / Lapsed |