Patent US3760201A successfully refreshed from Google Patents.
US3760201A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Optical flip-flop element
Assignee: Semiconductor Research Foundation
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Filing: 1971-09-16
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Granted: 1973-09-18
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Expires: 1991-09-16
Abstract
Abstract A semiconductor laser diode has two opposite parallel mirror end faces normal to its PN junction. With a forward current flowing through the PN junction, the application of an optical pulse to one of the mirror faces causes a sustained coherent light to be emitted through the other mirror face. When a coherent light from a similar diode falls upon the first diode, the latter terminates its emission. The pulse is again applied to the first diode to emit the coherent light from it. Thus both diodes form a FLIPFLOP. Those two diodes may be formed in a single semiconductor wafer.
Inventors
- 👤 J Nishizawa
- 👤 K Takahashi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 22:44
CPC Classifications
H; H01; H01S; H01S5/00; H01S5/06; H01S5/0607; H01S5/0608; G; G02; G02F; G02F3/00; G02F3/02; G02F3/026; H03; H03K; H03K3/00; H03K3/02; H03K3/42
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
258 words
An optical logic elemenT comprising, two semiconductor laser diodes, each semiconductor laser diode comprising reflective end faces defining therebetween a resonant cavity for emission of coherent light, each laser diode having a p-n junction disposed in a plane passing through said reflective end faces, said reflective end faces being disposed normal to said plane, biasing means for each laser diode so that a forward current flows through each p-n junction in operation and is insufficient to effect emission of coherent light from the individual diode but sufficient to sustain emission of coherent light upon termination of an input excitation light signal exciting the individual laser diode to emit coherent light, each laser diode having one of the reflective end faces disposed for receiving an input excitation light signal to produce a coherent light output from the other reflective end face, light-reflecting means coacting with said laser diodes and said laser diodes being arranged relative to each other and relative to said light-reflecting means for quenching of one of the laser diodes upon emission of coherent light by the other laser diode and application of the coherent light to said one laser diode for quenching thereof, whereby when said one of the diodes is excited by an input excitation light signal for emission of coherent light it emits coherent light including after the termination of the input excitation light signal and when said other laser diode is excited by an input excitation light signal for emission of coherent light it emits coherent light and quenches said one laser diode.
Claim 2
Dependent Claim
258 words
An optical logic elemenT comprising, two semiconductor laser diodes, each semiconductor laser diode comprising reflective end faces defining therebetween a resonant cavity for emission of coherent light, each laser diode having a p-n junction disposed in a plane passing through said reflective end faces, said reflective end faces being disposed normal to said plane, biasing means for each laser diode so that a forward current flows through each p-n junction in operation and is insufficient to effect emission of coherent light from the individual diode but sufficient to sustain emission of coherent light upon termination of an input excitation light signal exciting the individual laser diode to emit coherent light, each laser diode having one of the reflective end faces disposed for receiving an input excitation light signal to produce a coherent light output from the other reflective end face, light-reflecting means coacting with said laser diodes and said laser diodes being arranged relative to each other and relative to said light-reflecting means for quenching of one of the laser diodes upon emission of coherent light by the other laser diode and application of the coherent light to said one laser diode for quenching thereof, whereby when said one of the diodes is excited by an input excitation light signal for emission of coherent light it emits coherent light including after the termination of the input excitation light signal and when said other laser diode is excited by an input excitation light signal for emission of coherent light it emits coherent light and quenches said one laser diode.
Claim 3
Dependent Claim
29 words
An optical logic element according to claim 1, in which said biasing means comprises ohmic contacts on each respective laser diode and means applying constant biasing electric energy thereto.
Claim 4
Dependent Claim
96 words
An optical logic element according to claim 1, in which said biasing means comprises a constant voltage source connected to apply a voltage below a threshold level of the individual diodes for emission of coherent light without application of said input excitation light signal, and said semiconductor laser diodes each having a composition effective to sustain coherent light emission upon termination of said input excitation light signal, and said voltage source applying a biasing voltage signal effective to sustain said coherent light emission for a period of time when said input excitation light signal is terminated.
Claim 5
Dependent Claim
18 words
An optical logic element according to claim 1, in which said laser diodes comprise a unitary semiconductor body.
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) | 1976-09-17 | 1977-03-19 | 1977-09-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-09-17 | 1981-03-19 | 1981-09-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-09-17 | 1985-03-19 | 1985-09-18 | $7700.00 | Window Closed / Lapsed |