US3821778A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Infrared photocathode
Assignee: Raytheon Co
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Filing: 1972-12-04
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Granted: 1974-06-28
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Expires: 1992-12-04
Abstract
Abstract AN INFRARED PHOTOEMITTER AND PROCESS FOR FABRICATING SAME WHEREIN A THIN METAL LAYER IS SANDWICHED IN A COMPOSITE STRUCTURE BETWEEN A SUITABLE PHOTOABSORTIVE SEMICONDUCTIVE LAYER AND A LOW WORK FUNCTION INSULATING LAYER. THE SEMICONDUCTIVE LAYER SERVES AS A PHOTON ABSORBER AND PHOTOELECTION SOURCE FOR THE DEVICE. THE INSULATING LAYER IS CHOSEN FOR ITS LOW WORK FUNCTION. THE METAL INTERLAYER ELIMATES THE HETERJUNCTION WHICH IN ITS ABSENCE WOULD EXIST BETWEEN THE SEMICONDUCTIVE AND INSULATING LAYERS AND THEREBY ELIMINATES THE RESTRICTION THAT SUCH HETEROJUNCTIONS IMPOSE ON THE EFFICIENCY AND WAVELENGTH RESPONSE OF PRIOR ART COMPOSITION PHOTOEMITTERS.
Inventors
- 👤 S Kurtin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 06:12
CPC Classifications
H; H01; H01J; H01J1/00; H01J1/02; H01J1/34; H01J29/00; H01J29/02; H01J29/10; H01J29/36; H01J29/38; H01J2201/00; H01J2201/34; H01J2201/342; H01J2201/3421; H01J2201/3423; Y; Y10; Y10S; Y10S148/00; Y10S148/12
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-06-27 | 1977-12-27 | 1978-06-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-06-27 | 1981-12-27 | 1982-06-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-06-27 | 1985-12-27 | 1986-06-28 | $7700.00 | Window Closed / Lapsed |