US6572229B2
Expired / Lapsed
US
⏱️ 0.0 years remaining
Back projection visual field tester
Assignee: Carl Zeiss Meditec Inc
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Filing: 2001-06-14
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Granted: 2003-06-03
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Expires: 2021-06-14
Abstract
Abstract One embodiment of the present invention is a visual field tester that includes: (a) a projection screen; (b) a stimulus projection system that projects a light source onto a first side of the projection screen; (c) a background projection system that projects a background light onto the first side of the projection screen; and (d) a magnifier lens system disposed on a second side of the projection screen that directs light transmitted through the projection screen to a predetermined location.
Inventors
- 👤 Jay Wei
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 07:59
CPC Classifications
A; A61; A61B; A61B3/00; A61B3/02; A61B3/024
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
73 words
A visual field tester comprises: a projection screen; a stimulus projection system that projects a stimulus from a light source onto a first side of the projection screen; a background projection system that projects a substantially uniform background light onto the first side of the projection screen; and a magnifier lens system, disposed on a second side of the projection screen, that directs light transmitted through the projection screen to a predetermined location.
Claim 2
Dependent Claim
73 words
A visual field tester comprises: a projection screen; a stimulus projection system that projects a stimulus from a light source onto a first side of the projection screen; a background projection system that projects a substantially uniform background light onto the first side of the projection screen; and a magnifier lens system, disposed on a second side of the projection screen, that directs light transmitted through the projection screen to a predetermined location.
Claim 3
Dependent Claim
24 words
The visual field tester of claim 1 wherein the stimulus projection system comprises: the light source; a projection lens system; and a scanner system.
Claim 4
Dependent Claim
15 words
The visual field tester of claim 2 wherein the scanner system comprises a gimbal-mounted mirror.
Claim 5
Dependent Claim
15 words
The visual field tester of claim 2 wherein the scanner system further comprises a photodetector.
Claim 6
Dependent Claim
21 words
The visual field tester of claim 3 wherein the background projection system comprises a source that outputs substantially uniform background light.
Claim 7
Dependent Claim
46 words
The visual field tester of claim 1 wherein the stimulus projection system comprises: the light source that outputs light; an optical fiber system disposed to receive the light output; and a projection lens system that projects light output from the optical fiber onto the projection screen.
Claim 8
Dependent Claim
36 words
The visual field tester of claim 6 wherein the projection lens system has a predetermined depth of focus that is long enough so that the stimulus is focused over a large area of the projection screen.
Claim 9
Dependent Claim
26 words
The visual field tester of claim 7 wherein a numerical aperture of the projection lens system is small enough to achieve the predetermined depth of focus.
Claim 10
Dependent Claim
39 words
visual field tester of claim 1 wherein the stimulus projection system comprises: the light source having a relatively small aperture that outputs light; and a projection lens system that projects light output from the aperture onto the projection screen.
Claim 11
Dependent Claim
19 words
The visual field tester of claim 1 wherein the projection screen comprises: a lens element; and a diffuser element.
Claim 12
Dependent Claim
15 words
The visual field tester of claim 10 wherein the lens element comprises a Fresnel lens.
Claim 13
Dependent Claim
15 words
The visual field tester of claim 1 wherein the projection screen comprises a holographic diffuser.
Claim 14
Dependent Claim
56 words
The visual field tester of claim 1 which further comprises: a CCD camera; and a lens group to relay light transmitted by the projection screen and reflected, which reflected light is reflected from a patient's eye that is disposed at the predetermined location and which is transmitted through the magnifier lens system, to the CCD camera.
Claim 15
Dependent Claim
21 words
The visual field tester of claim 13 that further comprises a monitor that displays an image output from the CCD camera.
Claim 16
Dependent Claim
37 words
The visual field tester of claim 1 wherein: a blue filter is placed in an optical path of the stimulus projection system to generate a blue stimulus; and the background projection system comprises a yellow light source.
Claim 17
Dependent Claim
16 words
The visual field tester of claim 15 wherein the yellow light source comprises a yellow LED.
Claim 18
Dependent Claim
21 words
The visual field tester of claim 15 wherein the yellow light source comprises a white light source and a yellow filter.
References Cited (Backward Citations)
US4626090A
Cited
US4361382A
Cited
US5046835A
Cited
US5024519A
Cited
US5323194A
Cited
US5461436A
Cited
US5459536A
Cited
US5717481A
Cited
US5870169A
Cited
US6414727B1
Cited
US6315412B1
Cited
US6139150A
Cited
US6347012B1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2006-06-02 | 2006-12-02 | 2007-06-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2010-06-02 | 2010-12-02 | 2011-06-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2014-06-02 | 2014-12-02 | 2015-06-03 | $7700.00 | Window Closed / Lapsed |