Patent US3790868A successfully refreshed from Google Patents.
US3790868A
Expired / Lapsed
US
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Efficient red emitting electroluminescent semiconductor
Assignee: HP Inc
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Filing: 1972-10-27
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Granted: 1974-02-05
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Expires: 1992-10-27
Abstract
Abstract A solid state light source includes a gallium arsenide phosphide electroluminescent semiconductor in a mesa structure, a substrate substantially transparent to the radiation emitted by the semiconductor, a region of varying composition connecting the substrate to the semiconductor, and a reflective backing.
Inventors
- 👤 R Soshea
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 21:37
CPC Classifications
H; H10; H10H; H10H20/00; H10H20/80
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
31 words
Apparatus as in claim 1 wherein the substrate region is gallium arsenide phosphide wherein the phosphorus concentration is x and the arsenic concentration is (1-x), where x < or = 0.5.
Claim 2
Dependent Claim
8 words
Apparatus as in claim 2 wherein x 1.0.
Claim 3
Dependent Claim
21 words
Apparatus as in claim 1 wherein the junction region is included within a mesa shaped protrusion contiguous with the graded region.
Claim 4
Dependent Claim
22 words
Apparatus as in claim 1 wherein the composition of the graded region varies continuously from its upper surface to its lower surface.
Claim 5
Dependent Claim
24 words
Apparatus as in claim 1 wherein the composition of the graded region varies in discrete steps from its upper surface to its lower surface.
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) | 1977-02-04 | 1977-08-06 | 1978-02-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-02-04 | 1981-08-06 | 1982-02-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-02-04 | 1985-08-06 | 1986-02-05 | $7700.00 | Window Closed / Lapsed |