US5349465A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Optical democulator
Assignee: Japan Science and Technology Agency
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Filing: 1992-07-16
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Granted: 1994-09-20
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Expires: 2012-07-16
Abstract
Abstract An optical demodulator includes a nonlinear element which responds to both light and a microwave-submillimeter wave (far infrared radiation). An optical signal modulated by a modulating wave in which a subcarrier consisting of the microwave-submillimeter wave is modulated by a signal wave, and a local oscillated signal consisting of a microwave-submillimeter wave the same in frequency as the subcarrier are added to the nonlinear element, to fetch the signal wave by a heterodyne system.
Inventors
- 👤 Koji Mizuno
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 20:31
CPC Classifications
H; H04; H04B; H04B10/00; H04B10/60
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
113 words
An optical demodulator for demodulating a modulated optical signal wave to obtain a signal wave, said optical demodulator comprising: a semiconductor diode responsive to light and microwave-submillimeter waves; a waveguide circuit for applying a local oscillated signal to said semiconductor diode; and means for fetching a signal wave produced by said semiconductor diode by a heterodyne system, wherein said semiconductor diode produces the signal wave in response to simultaneous irradiation of said semiconductor diode with a modulated optical signal wave having a microwave-submillimeter subcarrier wave modulated by the signal wave, and application, via said waveguide circuit, of a local oscillated signal having the same frequency as the subcarrier wave to said semiconductor diode.
Claim 2
Dependent Claim
113 words
An optical demodulator for demodulating a modulated optical signal wave to obtain a signal wave, said optical demodulator comprising: a semiconductor diode responsive to light and microwave-submillimeter waves; a waveguide circuit for applying a local oscillated signal to said semiconductor diode; and means for fetching a signal wave produced by said semiconductor diode by a heterodyne system, wherein said semiconductor diode produces the signal wave in response to simultaneous irradiation of said semiconductor diode with a modulated optical signal wave having a microwave-submillimeter subcarrier wave modulated by the signal wave, and application, via said waveguide circuit, of a local oscillated signal having the same frequency as the subcarrier wave to said semiconductor diode.
Claim 3
Dependent Claim
15 words
An optical demodulator according to claim 1, wherein said waveguide circuit is a microstrip line.
Claim 4
Dependent Claim
73 words
An optical demodulator for demodulation of an optical signal by a heterodyne system, comprising: a waveguide circuit; a semiconductor diode responsive to light waves and microwave-submillimeter waves for obtaining a signal wave from a modulated optical signal, said semiconductor diode loaded on said waveguide circuit, and generating optical conductive current when irradiated with an optical signal; and means for fetching the optical conductive current produced by said semiconductor diode by a heterodyne system.
Claim 5
Dependent Claim
73 words
An optical demodulator for demodulation of an optical signal by a heterodyne system, comprising: a waveguide circuit; a semiconductor diode responsive to light waves and microwave-submillimeter waves for obtaining a signal wave from a modulated optical signal, said semiconductor diode loaded on said waveguide circuit, and generating optical conductive current when irradiated with an optical signal; and means for fetching the optical conductive current produced by said semiconductor diode by a heterodyne system.
Claim 6
Independent Claim
55 words
A method of demodulating a modulated optical signal having a subcarrier microwave-submillimeter wave modulated by a signal wave to obtain the signal wave, comprising the steps of: irradiating the modulated optical signal on a semiconductor diode, and simultaneously applying a local oscillated wave having the same frequency as the subcarrier wave to said semiconductor diode.
Claim 7
Independent Claim
55 words
A method of demodulating a modulated optical signal having a subcarrier microwave-submillimeter wave modulated by a signal wave to obtain the signal wave, comprising the steps of: irradiating the modulated optical signal on a semiconductor diode, and simultaneously applying a local oscillated wave having the same frequency as the subcarrier wave to said semiconductor diode.
Claim 8
Dependent Claim
16 words
A method as in claim 4, further comprising the step of fetching the obtained signal wave.
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| 3.5 Years (Year 4) | 1997-09-19 | 1998-03-21 | 1998-09-20 | $2000.00 | Window Closed / Lapsed |
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