Patent US3976874A successfully refreshed from Google Patents.
US3976874A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Image tube incorporating a brightness-dependent power supply
Assignee: US Philips Corp
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Filing: 1975-10-06
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Granted: 1976-08-24
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Expires: 1995-10-06
Abstract
Abstract The invention relates to a noctoviser comprising an image intensifier tube and a cascade high-voltage generator in which the intensifier tube is connected to the output of the high voltage generator via a parallel connection of a resistor and an avalanche diode.
Inventors
- 👤 Gerhard Lange
- 👤 Detlef Falk
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 18:23
CPC Classifications
H; H01; H01J; H01J29/00; H01J29/98
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
108 words
A noctoviser having automatic brightness compensation, comprising: an image intensifier tube; a high-voltage generator for producing a substantially constant high-voltage; a resistor directly connecting said high-voltage generator to said image intensifier tube to reduce the high-voltage delivered to said tube as the tube current increases; and an avalanche diode connected in parallel with said resistor to limit the high-voltage reduction by said resistor in order to prevent said tube from switching-off at very high brightness input levels, said parallel connected resistor and diode effectively varying the high-voltage delivered to said tube such that the output luminescence of said tube remains approximately the same at all brightness input levels.
Claim 2
Dependent Claim
108 words
A noctoviser having automatic brightness compensation, comprising: an image intensifier tube; a high-voltage generator for producing a substantially constant high-voltage; a resistor directly connecting said high-voltage generator to said image intensifier tube to reduce the high-voltage delivered to said tube as the tube current increases; and an avalanche diode connected in parallel with said resistor to limit the high-voltage reduction by said resistor in order to prevent said tube from switching-off at very high brightness input levels, said parallel connected resistor and diode effectively varying the high-voltage delivered to said tube such that the output luminescence of said tube remains approximately the same at all brightness input levels.
Claim 3
Dependent Claim
37 words
A noctoviser as defined in claim 1 and further comprising a second resistor connected in series with said avalanche diode, said series connected avalanche diode and second resistor being directly connected in parallel with the first resistor.
Claim 4
Dependent Claim
79 words
A noctoviser as defined in claim 2 and further comprising a second stage comprising: a second image intensifier tube connected in series with the first image intensifier tube; a second high-voltage generator connected in series with the first high-voltage generator for powering said second image intensifier tube; a third resistor directly connecting said second high-voltage generator to said second image intensifier tube; and a second avalanche diode and a fourth resistor connected in series directly across said third resistor.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-08-24 | 1980-02-23 | 1980-08-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-08-24 | 1984-02-23 | 1984-08-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-08-24 | 1988-02-23 | 1988-08-24 | $7700.00 | Window Closed / Lapsed |