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US4063807A
Expired / Lapsed
US
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Perimetric eye testing device
Assignee: Optische Werke G Rodenstock
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Filing: 1976-02-20
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Granted: 1977-12-20
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Expires: 1996-02-20
Abstract
Abstract A perimetric eye examination device is provided having light-emitting diodes for the respective light sources which are perceived during the eye examinations. These light-emitting diodes are controllable for their brightness, either in linear dependence on the current, or in linear dependence on the pulse width repetition ratio of current pulses supplied to the light-emitting diode. The brightness perceived from the respective light-emitting diodes on the surface of the perimetric eye examination device also may be varied in accordance with physiological characteristics of the eye wherein the light-emitting diodes are distributed on the surface of the device with the brightness increasing from the central area of the observation area toward the periphery of the observation area.
Inventors
- 👤 Siegfried Gelius
- 👤 Hanne-Lore Wieczorek
- 👤 Adolf Triller
- 👤 Nils Nielsen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 14:23
CPC Classifications
A; A61; A61B; A61B3/00; A61B3/02; A61B3/024; A61B3/06; A61B3/066
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
121 words
In a perimetric eye examination device including a viewing area in the form of a hemispherical inner surface, a plurality of light sources of small surface area disposed in said surface, and capable of being activated in groups or individually, and a fixation point in said surface, the improvement comprising each of said light sources including light-emitting diodes, and luminous density control means for changing the brightness impression of the light-emitting diodes, said control means comprising current pulse means for supplying current pulses of uniform amplitude and at a pulse repetition frequency greater than the flicker frequency to each of said light-emitting diodes, and means for varying the pulse width repetition ratio of said current pulses supplied to said light-emitting diodes.
Claim 2
Dependent Claim
121 words
In a perimetric eye examination device including a viewing area in the form of a hemispherical inner surface, a plurality of light sources of small surface area disposed in said surface, and capable of being activated in groups or individually, and a fixation point in said surface, the improvement comprising each of said light sources including light-emitting diodes, and luminous density control means for changing the brightness impression of the light-emitting diodes, said control means comprising current pulse means for supplying current pulses of uniform amplitude and at a pulse repetition frequency greater than the flicker frequency to each of said light-emitting diodes, and means for varying the pulse width repetition ratio of said current pulses supplied to said light-emitting diodes.
Claim 3
Dependent Claim
43 words
A perimetric eye examination device according to claim 1, wherein said light-emitting diodes are distributed over the viewing area of said inner surface, and the luminous density of said light-emitting diodes increases from the center of the viewing area toward the periphery thereof.
Claim 4
Dependent Claim
21 words
A perimetric eye examination device according to claim 1, wherein said fixation point is constituted by one of said light-emitting diodes.
Claim 5
Dependent Claim
18 words
A perimetric eye examination device according to claim 1, wherein said light-emitting diodes emit light of different colors.
Claim 6
Dependent Claim
33 words
A perimetric eye examination device according to claim 4, wherein means for electrically controlling each of said light-emitting diodes is provided for varying the color of the light emitted by the respective diode.
Claim 7
Dependent Claim
17 words
A perimetric eye examination device according to claim 1, wherein said current pulses have a rectangular configuration.
Claim 8
Dependent Claim
35 words
A perimetric eye examination device according to claim 6, wherein said current pulse means and said means for varying the pulse width repetition ratio include a pulse generator and a pulse width control circuit respectively.
Claim 9
Dependent Claim
35 words
A perimetric eye examination device according to claim 1, wherein said current pulse means and said means for varying the pulse width repetition ratio include a pulse generator and a pulse frequency control circuit, respectively.
Claim 10
Dependent Claim
51 words
A perimetric eye examination device according to claim 1, wherein said luminous density control means effects linear brightness impression by the eye independently of the luminous density-current relationship of said light-emitting diodes so as to operate said light-emitting diodes in non-linear regions of the luminous density-current relationship of said light-emitting diodes.
References Cited (Backward Citations)
US3421498A
Cited
US3837734A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-12-19 | 1981-06-20 | 1981-12-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-12-19 | 1985-06-20 | 1985-12-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-12-19 | 1989-06-20 | 1989-12-20 | $7700.00 | Window Closed / Lapsed |