US4145123A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Perimeter
Assignee: Optische Werke G Rodenstock
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Filing: 1977-03-16
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Granted: 1979-03-20
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Expires: 1997-03-16
Abstract
Abstract A perimeter for perimetric eye testing is provided with an electronic control mechanism for varying the brightness of the light signals in a preselected manner such that reproducibility of the examination can be achieved. An optical indicating arrangement is included to indicate the brightness values to the examiner, while the electronic control mechanism can further control an electronic recorder for recording the results of the examination.
Inventors
- 👤 Wilhelm E. Krahn
- 👤 Manfred Born
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 16:57
CPC Classifications
A; A61; A61B; A61B3/00; A61B3/02; A61B3/06; A61B3/024
Claims Analysis
Total Claims: 29
Claim 1
Independent Claim
165 words
A perimeter for perimetric examinations comprising: at least one projector for introducing fixed or movable light signals of varying size and brightness on an approximately hemispherical projection area, filter means including a plurality of different filters for attenuating the projected light beam of said projector, drive means for varying said filter means introduced into said light beam, and electronic control means for actuating said drive means for switching said different filters into said projected light beam, either individually or in groups, to selectively increase or decrease the attenuation of said projected light beam and vary brightness of said light signals to introduce a light signal having a predetermined brightness value on said hemispherical projection area, said electronic control means including means for effecting switching of said different filters stepwise in preselected time intervals, and means for effecting a preselected dark interval at which said light beam is not projected to said projection area, said stepwise switching of said different filters occurring during said dark interval.
Claim 2
Dependent Claim
165 words
A perimeter for perimetric examinations comprising: at least one projector for introducing fixed or movable light signals of varying size and brightness on an approximately hemispherical projection area, filter means including a plurality of different filters for attenuating the projected light beam of said projector, drive means for varying said filter means introduced into said light beam, and electronic control means for actuating said drive means for switching said different filters into said projected light beam, either individually or in groups, to selectively increase or decrease the attenuation of said projected light beam and vary brightness of said light signals to introduce a light signal having a predetermined brightness value on said hemispherical projection area, said electronic control means including means for effecting switching of said different filters stepwise in preselected time intervals, and means for effecting a preselected dark interval at which said light beam is not projected to said projection area, said stepwise switching of said different filters occurring during said dark interval.
Claim 3
Dependent Claim
21 words
A perimeter according to claim 1, wherein a single stepwise switching of an individual filter is effected during said dark interval.
Claim 4
Dependent Claim
28 words
A perimeter according to claim 1, wherein a stepwise switching of a group of a predetermined number of individual filters is effected in succession during said dark interval.
Claim 5
Dependent Claim
21 words
A perimeter according to claim 3, wherein said group includes five individual filters being switched in succession during said dark interval.
Claim 6
Dependent Claim
35 words
A perimeter according to claim 1, wherein said electronic control means continuously effects said stepwise switching until a predetermined filter is introduced into said projected light beam such that said predetermined brightness value is provided.
Claim 7
Dependent Claim
20 words
A perimeter according to claim 1, wherein indicating means are provided for indicating the brightness value of said light signals.
Claim 8
Dependent Claim
42 words
A perimeter according to claim 6, wherein said indicating means includes an indicia means for providing a numerical scale of said brightness values and light source means associated with said brightness values for indicating said predetermined brightness value on said numerical scale.
Claim 9
Dependent Claim
29 words
A perimeter according to claim 7, wherein said light source means includes a plurality of light-emitting diodes, each of said light-emitting diodes being associated with a given brightness value.
Claim 10
Dependent Claim
30 words
A perimeter according to claim 8, wherein a printed diagram sheet for recording results of the examinations by the perimeter is arranged with graduations in association with said numerical scale.
Claim 11
Dependent Claim
27 words
A perimeter according to claim 9, wherein said printed diagram sheet covers said light source means and has a plurality of perforations associated with said light-emitting diodes.
Claim 12
Dependent Claim
22 words
A perimeter according to claim 7, wherein said electronic control means further controls recording means for recording results of the perimetric examinations
Claim 13
Dependent Claim
42 words
A perimeter according to claim 1, further comprising indicating means including an indicia means for providing a numerical scale of said brightness values and light source means associated with said brightness values for indicating said predetermined brightness value on said numerical scale.
Claim 14
Dependent Claim
29 words
A perimeter according to claim 12, wherein said light source means includes a plurality of light-emitting diodes, each of said light-emitting diodes being associated with a given brightness value.
Claim 15
Dependent Claim
30 words
A perimeter according to claim 13, wherein a printed diagram sheet for recording results of the examinations by the perimeter is arranged with graduations in association with said numerical scale.
Claim 16
Dependent Claim
27 words
A perimeter according to claim 14, wherein said printed diagram sheet covers said light source means and has a plurality of perforations associated with said light-emitting diodes.
Claim 17
Dependent Claim
22 words
A perimeter according to claim 1, wherein said electronic control means further controls recording means for recording results of the perimetric examinations.
Claim 18
Dependent Claim
103 words
In a perimeter including at least one projector for projecting a beam of light to a perimetric surface, filter means including a plurality of filters for attenuating said beam of light, drive means for changing said plurality of filters, and electronic control means for controlling said perimeter, the improvement comprising said electronic control means including means for activating said drive means and switching at least one filter during a predetermined time interval, means for providing light and dark intervals of said projected light, said predetermined time interval occurring only during said dark interval, and means for adjusting the length of said dark interval.
Claim 19
Dependent Claim
103 words
In a perimeter including at least one projector for projecting a beam of light to a perimetric surface, filter means including a plurality of filters for attenuating said beam of light, drive means for changing said plurality of filters, and electronic control means for controlling said perimeter, the improvement comprising said electronic control means including means for activating said drive means and switching at least one filter during a predetermined time interval, means for providing light and dark intervals of said projected light, said predetermined time interval occurring only during said dark interval, and means for adjusting the length of said dark interval.
Claim 20
Dependent Claim
20 words
A perimeter according to claim 17, wherein a single stepwise switching of one filter is effected during said dark interval.
Claim 21
Dependent Claim
28 words
A perimeter according to claim 17, wherein a stepwise switching of a group of a predetermined number of said filters is effected in succession during said dark interval.
Claim 22
Dependent Claim
20 words
A perimeter according to claim 19, wherein said group includes five filters being switched in succession during said dark interval.
Claim 23
Dependent Claim
37 words
A perimeter according to claim 17, wherein said electronic control means continuously effects stepwise switching of said filters until a predetermined filter is introduced into said projected light beam such that a predetermined brightness value is provided.
Claim 24
Dependent Claim
21 words
A perimeter according to claim 17, wherein indicating means are provided for indicating brightness values of said projected beam of light.
Claim 25
Dependent Claim
42 words
A perimeter according to claim 22, wherein said indicating means includes an indicia means for providing a numerical scale of said brightness values and light source means associated with said brightness values for indicating said predetermined brightness value on said numerical scale.
Claim 26
Dependent Claim
29 words
A perimeter according to claim 23, wherein said light source means includes a plurality of light-emitting diodes, each of said light-emitting diodes being associated with a given brightness value.
Claim 27
Dependent Claim
30 words
A perimeter according to claim 24, wherein a printed diagram sheet for recording results of the examinations by the perimeter is arranged with graduations in association with said numerical scale.
Claim 28
Dependent Claim
27 words
A perimeter according to claim 25, wherein said printed diagram sheet covers said light source means and has a plurality of perforations associated with said light-emitting diodes.
Claim 29
Dependent Claim
21 words
A perimeter according to claim 17, wherein said electronic control means further controls recording means for recording results of perimetric examinations.
References Cited (Backward Citations)
US3288546A
Cited
US3664732A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-03-19 | 1982-09-18 | 1983-03-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-03-19 | 1986-09-18 | 1987-03-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-03-19 | 1990-09-18 | 1991-03-20 | $7700.00 | Window Closed / Lapsed |