Patent US4533227A successfully refreshed from Google Patents.
US4533227A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Distance measuring circuit
Assignee: Ricoh Co Ltd
•
Filing: 1984-04-13
•
Granted: 1985-08-06
•
Expires: 2004-04-13
Abstract
Abstract A distance measuring circuit controls in a given sequence a distance measuring operation in which a light beam is periodically projected to a target by means of a light projector and reflected light from the target is received by a light receiver, the output signal of which is utilized to determine the distance to the target. When the light projector is not energized, a capacitor is charged by a d.c. source, and discharges to drive the light projector when the light beam is to be projected.
Inventors
- 👤 Akira Takahashi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 22:33
CPC Classifications
G; G02; G02B; G02B7/00; G02B7/28; G02B7/30; G02B7/32; G01; G01S; G01S17/00; G01S17/02; G01S17/06; G01S17/08; G01S17/10
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
143 words
A distance measuring circuit comprising: a light projecting means for projecting a light beam toward a target; a light receiver means for receiving reflected light from said target and outputting a signal; and means for determining the level of said signal from said light receiver means including a plurality of amplifiers with each of said amplifiers having a different gain and each of said amplifiers outputting an amplified signal and wherein said determining means further includes a plurality of comparison means for comparing the respective said amplified output signals from said plurality of amplifiers with respective associated reference voltages, wherein the gain of each of said amplifiers is determined in accordance with each of said respective reference voltages whereby the operation of said light projecting means, said light receiver means and said determining means is controlled in a predetermined sequence by control means.
Claim 2
Dependent Claim
143 words
A distance measuring circuit comprising: a light projecting means for projecting a light beam toward a target; a light receiver means for receiving reflected light from said target and outputting a signal; and means for determining the level of said signal from said light receiver means including a plurality of amplifiers with each of said amplifiers having a different gain and each of said amplifiers outputting an amplified signal and wherein said determining means further includes a plurality of comparison means for comparing the respective said amplified output signals from said plurality of amplifiers with respective associated reference voltages, wherein the gain of each of said amplifiers is determined in accordance with each of said respective reference voltages whereby the operation of said light projecting means, said light receiver means and said determining means is controlled in a predetermined sequence by control means.
References Cited (Backward Citations)
US4032934A
Cited
US4256995A
Cited
US4268137A
Cited
US4313655A
Cited
US4303319A
Cited
US4298258A
Cited
US4344024A
Cited
US4300824A
Cited
US4302084A
Cited
US4357083A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-08-05 | 1989-02-04 | 1989-08-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-08-05 | 1993-02-04 | 1993-08-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-08-05 | 1997-02-04 | 1997-08-06 | $7700.00 | Window Closed / Lapsed |