Patent US4976538A successfully refreshed from Google Patents.
US4976538A
Expired / Lapsed
US
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Detection and display device
Assignee: Trimble Inc
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Filing: 1989-10-30
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Granted: 1990-12-11
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Expires: 2009-10-30
Abstract
Abstract A device for detecting and displaying the relative position of a generally horizontal reference plane of light, even when partial shading of the device occurs, produces a linear response that is independent of spot size and energy distribution. The device includes a photodetector means having first and second interdigitated photodetector elements positioned adjacent each other on the device. The first and second interdigitated photodetector elements provide first and second detection signals, respectively. A circuit means, responsive to the photodetector means, determines the relative levels of the first and second detection signals such that the position of the reference plane of light with respect to the detector device is determined. A display means, responsive to the circuit means, provides an indication of the position of the reference plane of light with respect to the detector device.
Inventors
- 👤 DuWain K. Ake
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 09:40
CPC Classifications
G; G01; G01C; G01C15/00; G01C15/002; G01C15/004; G01C15/006
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
181 words
A device for use with a transmitter which produces a beam of light having an energy distribution, the device capable of detecting and displaying the relative position of a generally horizontal reference plane of light, said device generating a linear response which is independent of beam size and energy distribution, comprising: photodetector means, including first and second interdigitated photodetector elements positioned adjacent each other on said device, said first and second interdigitated photodetector elements providing first and second detection signals, respectively, said first and second interdigitated photodetector elements having a plurality of sections arranged in a generally vertically oriented row, wherein each section has at least one leg portion which is inclined with respect to said row, circuit means, responsive to said photodetector means, for determining the relative levels of said first and second detection signals such that the position of said reference plane of light with respect to said detector device is determined, and display means, responsive to said circuit means, for providing an indication of said position of said reference plane of light with respect to said detector device.
Claim 2
Independent Claim
181 words
A device for use with a transmitter which produces a beam of light having an energy distribution, the device capable of detecting and displaying the relative position of a generally horizontal reference plane of light, said device generating a linear response which is independent of beam size and energy distribution, comprising: photodetector means, including first and second interdigitated photodetector elements positioned adjacent each other on said device, said first and second interdigitated photodetector elements providing first and second detection signals, respectively, said first and second interdigitated photodetector elements having a plurality of sections arranged in a generally vertically oriented row, wherein each section has at least one leg portion which is inclined with respect to said row, circuit means, responsive to said photodetector means, for determining the relative levels of said first and second detection signals such that the position of said reference plane of light with respect to said detector device is determined, and display means, responsive to said circuit means, for providing an indication of said position of said reference plane of light with respect to said detector device.
Claim 3
Dependent Claim
47 words
The device of claim 1 for detecting and displaying the relative position of a generally horizontal reference plane of light, in which each section of said first and second interdigitated photodetector elements has three leg portions, each such leg portion being inclined with respect to said row.
Claim 4
Dependent Claim
40 words
The device of claim 2 for detecting and displaying the relative position of a generally horizontal reference plane of light, in which each said leg portion is inclined in an alternate direction with respect to the length of said row.
Claim 5
Dependent Claim
33 words
The device of claim 2 for detecting and displaying the relative position of a generally horizontal reference plane of light, in which each of said leg portions vary in height along the row.
Claim 6
Dependent Claim
28 words
The device of claim 1 for detecting and displaying the relative position of a generally horizontal reference plane of light, in which said sections are generally chevron shaped.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-12-10 | 1994-06-11 | 1994-12-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-12-10 | 1998-06-11 | 1998-12-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-12-10 | 2002-06-11 | 2002-12-11 | $7700.00 | Window Closed / Lapsed |