US5164581A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Concentric photoelectric light-receiving element
Assignee: Sumitomo Electric Industries Ltd
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Filing: 1990-09-27
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Granted: 1992-11-17
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Expires: 2010-09-27
Abstract
Abstract An invention provides a light receiving element which can monitor a light signal input without causing a disturbance in an output signal. A light receiving element has a first active area irradiated by a major component of an input light signal and a second active area irradiated by a leakage light component of the input light signal. An output optical current for information transmission is generated by the light signal radiated on the first active area, and a monitor light output current is generated by the leakage light component of the light signal radiated on the second active area.
Inventors
- 👤 Nobuo Shiga
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 04:10
CPC Classifications
H; H04; H04B; H04B10/00; H04B10/60; H04B10/66; H10; H10F; H10F30/00; H10F30/20; H10F30/21; H10F30/22; H10F30/223; H10F39/00; H10F39/10; H10F39/103
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
168 words
A light receiving device comprising: (a) a light receiving element including: a first active area for receiving a major light component of an input optical signal to generate an optical current in response thereto for use in information transmission; and a second active area located so as to surround said first active area, said second active area receiving a leakage light component of said input optical signal to generate a monitor current for use in monitoring said input optical signal; (b) first amplifying means connected to said first active area through a first resistor for amplifying said optical current to form a first output signal; and (c) second amplifying means connected to said second active area through a second resistor for amplifying said monitor signal, said second amplifying means and said second resistor constituting a monitor circuit, said first amplifying means and said first resistor constituting a signal amplifying circuit, and said monitor circuit having a time constant which is larger than that of said signal amplifying circuit.
Claim 2
Dependent Claim
168 words
A light receiving device comprising: (a) a light receiving element including: a first active area for receiving a major light component of an input optical signal to generate an optical current in response thereto for use in information transmission; and a second active area located so as to surround said first active area, said second active area receiving a leakage light component of said input optical signal to generate a monitor current for use in monitoring said input optical signal; (b) first amplifying means connected to said first active area through a first resistor for amplifying said optical current to form a first output signal; and (c) second amplifying means connected to said second active area through a second resistor for amplifying said monitor signal, said second amplifying means and said second resistor constituting a monitor circuit, said first amplifying means and said first resistor constituting a signal amplifying circuit, and said monitor circuit having a time constant which is larger than that of said signal amplifying circuit.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-11-17 | 1996-05-18 | 1996-11-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-11-17 | 2000-05-18 | 2000-11-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-11-17 | 2004-05-18 | 2004-11-17 | $7700.00 | Window Closed / Lapsed |