US4382180A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Image intensifier devices
Assignee: Teledyne UK Ltd
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Filing: 1979-05-30
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Granted: 1983-05-03
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Expires: 1999-05-30
Abstract
Abstract The invention provides a multi stage image intensifier arrangement in which, for any stage, means are provided responsive to the photo current of the stage for discharging capacitance associated with that stage so as to limit the level of current density to which the anode screen of that stage is subjected as a result of a high intensity input flash of light.
Inventors
- 👤 Anthony J. Woolgar
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 11:54
CPC Classifications
H; H01; H01J; H01J31/00; H01J31/08; H01J31/50; H01J31/501; H01J29/00; H01J29/98
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
112 words
An image intensifier arrangement including at least one stage and means responsive to the photo current of said stage for discharging capacitance associated with that or another stage, whereby to limit the level of current density to which the anode screen of said last mentioned stage is subjected as a result of a high intensity input flash of light, wherein said responsive means comprises a resistance in a supply path for operating potential to either the photo cathode or the anode screen of a stage, an a.c. coupled amplifier connected across said resistance and providing an output, and an active device triggerable by said amplifier output to discharge said capacitance as aforesaid.
Claim 2
Dependent Claim
112 words
An image intensifier arrangement including at least one stage and means responsive to the photo current of said stage for discharging capacitance associated with that or another stage, whereby to limit the level of current density to which the anode screen of said last mentioned stage is subjected as a result of a high intensity input flash of light, wherein said responsive means comprises a resistance in a supply path for operating potential to either the photo cathode or the anode screen of a stage, an a.c. coupled amplifier connected across said resistance and providing an output, and an active device triggerable by said amplifier output to discharge said capacitance as aforesaid.
Claim 3
Dependent Claim
30 words
An arrangement as claimed in claim 1 and wherein said responsive means comprises a resistance in the supply path for operating potential to the photo cathode of the first stage.
Claim 4
Dependent Claim
31 words
An arrangement as claimed in claim 1 and wherein said active device comprises means for illuminating the photo cathode of a stage the associated capacitance of which is to be discharged.
Claim 5
Dependent Claim
35 words
An arrangement as claimed in claim 3 and wherein said illuminating means is provided external of the envelope of the stage, and is arranged to illuminate the front of the photo cathode of the stage.
Claim 6
Dependent Claim
26 words
An arrangement as claimed in claim 3 and wherein said illuminating means comprises one or more high speed flash tubes, light emitting diodes, or laser diodes.
Claim 7
Dependent Claim
30 words
An arrangement as claimed in claim 1 and wherein said active device is a high voltage switching device connected between the photo cathode and the anode screen of a stage.
Claim 8
Dependent Claim
23 words
An arrangement as claimed in claim 6 and wherein said active device comprises one or more gas filled switching tubes, thyristors, or transistors.
Claim 9
Dependent Claim
50 words
An arrangement as claimed in claim 1 and wherein said image intensifier is a multi stage image intensifier and said responsive means is provided to be responsive to the photo current of said first stage and said capacitance discharging means is provided in respect of at least that first stage.
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) | 1986-05-02 | 1986-11-01 | 1987-05-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-05-02 | 1990-11-01 | 1991-05-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-05-02 | 1994-11-01 | 1995-05-03 | $7700.00 | Window Closed / Lapsed |