Patent US4582404A successfully refreshed from Google Patents.
US4582404A
Expired / Lapsed
US
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Sagometer
Assignee: Individual
•
Filing: 1984-07-16
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Granted: 1986-04-15
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Expires: 2004-07-16
Abstract
Abstract An optical instrument which measures with great accuracy certain anatomical dimensions of an eye utilizing finite light beams which strike the eye from pre-determined angles and distances. The instrument measures, among other things, the critical sagittal depth of the eye where the finite light beams converge at a recognizable point. The measurements provide optimal fitting of a contact lens to the eye.
Inventors
- 👤 C. B. Hamilton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 12:54
CPC Classifications
A; A61; A61B; A61B3/00; A61B3/10; A61B3/107
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
238 words
An optical instrument for measuring certain anatomical dimensions of the eye, comprising: a housing; a view screen assembly, with an optical axis, mounted to the housing; an ocular assembly, with an optical axis, mounted to the housing; an illuminator adapted to the housing; an illuminator mirror positioned within the housing to reflect light from the illuminator to the eye; a fixation point mounted to the illuminator upon which the eye can focus thereby aligning the optical axis of the ocular assembly with the line of vision of the eye; a semi-transparent mirror positioned in the housing to receive the image of the illuminated eye; a lens system, with an optical axis, mounted within the housing to magnify and focus the eye upon the view screen assembly; means for centering the image of the eye with respect to the optical axis of the view screen assembly; means for reflecting and illuminating the image of the eye to be examined upon the view screen assembly; a plurality of movable slit light sources within the ocular assembly adapted to project finite light beams upon the eye with respect to the optical axis of the ocular assembly; means to move the plurality of movable slit light sources along an axis parallel to the optical axis of the ocular assembly until the slit light beams converge at a common point; and means to measure the parallel movement of the movable slit light sources.
Claim 2
Dependent Claim
238 words
An optical instrument for measuring certain anatomical dimensions of the eye, comprising: a housing; a view screen assembly, with an optical axis, mounted to the housing; an ocular assembly, with an optical axis, mounted to the housing; an illuminator adapted to the housing; an illuminator mirror positioned within the housing to reflect light from the illuminator to the eye; a fixation point mounted to the illuminator upon which the eye can focus thereby aligning the optical axis of the ocular assembly with the line of vision of the eye; a semi-transparent mirror positioned in the housing to receive the image of the illuminated eye; a lens system, with an optical axis, mounted within the housing to magnify and focus the eye upon the view screen assembly; means for centering the image of the eye with respect to the optical axis of the view screen assembly; means for reflecting and illuminating the image of the eye to be examined upon the view screen assembly; a plurality of movable slit light sources within the ocular assembly adapted to project finite light beams upon the eye with respect to the optical axis of the ocular assembly; means to move the plurality of movable slit light sources along an axis parallel to the optical axis of the ocular assembly until the slit light beams converge at a common point; and means to measure the parallel movement of the movable slit light sources.
Claim 3
Dependent Claim
23 words
The optical instrument of claim 1 wherein the plurality of movable slit light sources comprise: a pair of distinctively colored slit light beams.
Claim 4
Dependent Claim
94 words
The optical instrument of claim 1 wherein the view screen assembly comprises: a fixed barrel; a collar rotatably mounted to the fixed barrel at its distal end; a contact lens diameter indicator attached to the collar; a spiroidal screen rotatably mounted to the fixed barrel in such a way that the screen rotates about the optical axis of the view screen assembly and is connected to the collar; and a cross-hair screen mounted to the fixed barrel in such a way that the cross-hair screen is co-planar with and adjacent to the spiroidal screen.
Claim 5
Dependent Claim
32 words
The optical instrument of claim 1 wherein the means for reflecting and illuminating the image of the eye to be examined upon the view screen comprises: a combination semi-transparent and semi-reflective mirror.
Claim 6
Dependent Claim
47 words
The optical instrument of claim 1 wherein the plurality of movable slit light sources comprises: a lamp for each light source; a lamp casing with a slit; and means for connecting the lamp casing to the means which measures the parallel movement of the slit light sources.
Claim 7
Dependent Claim
24 words
The optical instrument of claim 1 wherein the means to measure the parallel movement of the movable slit light sources comprises: a micrometer assembly.
Claim 8
Dependent Claim
27 words
The optical instrument of claim 1 further comprising: means to convert the parallel movement measurement of the slit light sources directly to the radius of curvature measurement.
Claim 9
Dependent Claim
21 words
The optical instrument of claim 1 further comprising: a diffuser mounted to the illuminator to diffuse the light from the illuminator.
Claim 10
Dependent Claim
27 words
The optical instrument of claim 1 wherein the plurality of movable slit light sources comprise: a pair of beams, one (1) red and one (1) green colored.
References Cited (Backward Citations)
US2174308A
Cited
US3781096A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-04-14 | 1989-10-14 | 1990-04-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-04-14 | 1993-10-14 | 1994-04-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-04-14 | 1997-10-14 | 1998-04-15 | $7700.00 | Window Closed / Lapsed |