US3733492A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Gateable image intensifier tube
Assignee: Machlett Laboratories Inc
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Filing: 1972-04-03
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Granted: 1973-05-15
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Expires: 1992-04-03
Abstract
Abstract An image intensifier tube comprising an elongated envelope having therein axially spaced electrodes including a gateable photocathode located adjacent an input faceplate at one end of the envelope and low voltage means for increasing the intensity of an electrostatic field adjacent the photocathode without adversely affecting other interelectrode fields established within the tube envelope, thereby achieving an in-focus image having substantially constant brightness during the gating interval.
Inventors
- 👤 R Hagar
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 00:11
CPC Classifications
H; H01; H01J; H01J31/00; H01J31/08; H01J31/50; H01J31/501
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
129 words
A gateable image intensifier tube comprising: an elongated envelope; a photocathode disposed within the envelope adjacent one end thereof; an imaging screen disposed within the envelope adjacent the other end thereof; first means for establishing a first accelerating field adjacent the photocathode; second means for establishing a second accelerating field adjacent the imaging screen, the second accelerating field having a greater intensity than the first accelerating field; third means for establishing a decelerating field between the first and second accelerating fields, the decelerating field normally having a magnitude of intensity greater than that of the first accelerating field but less than that of the second accelerating field; and fourth means for varying the intensity of the first accelerating field independently of the decelerating field and the second accelerating field.
Claim 2
Dependent Claim
129 words
A gateable image intensifier tube comprising: an elongated envelope; a photocathode disposed within the envelope adjacent one end thereof; an imaging screen disposed within the envelope adjacent the other end thereof; first means for establishing a first accelerating field adjacent the photocathode; second means for establishing a second accelerating field adjacent the imaging screen, the second accelerating field having a greater intensity than the first accelerating field; third means for establishing a decelerating field between the first and second accelerating fields, the decelerating field normally having a magnitude of intensity greater than that of the first accelerating field but less than that of the second accelerating field; and fourth means for varying the intensity of the first accelerating field independently of the decelerating field and the second accelerating field.
Claim 3
Dependent Claim
25 words
A gateable image intensifier tube as set forth in claim 1 wherein the first means includes means for applying a bias potential to the photocathode.
Claim 4
Dependent Claim
26 words
A gateable image intensifier tube as set forth in claim 2 wherein the fourth means includes means for applying a gating signal voltage to the photocathode.
Claim 5
Dependent Claim
52 words
A gateable image intensifier tube as set forth in claim 3 wherein the signal voltage is sufficiently negative with respect to the bias potential to increase the first accelerating field magnitude of intensity to a value greater than that of the decelerating field but less than that of the second accelerating field.
Claim 6
Dependent Claim
46 words
A gateable image intensifier tube as set forth in claim 2 wherein the first means includes an apertured electrode disposed within the envelope in spaced opposing relationship with the photocathode and means for maintaining apertured apertured electrode at a positive potential with respect to the photocathode.
Claim 7
Dependent Claim
45 words
A gateable image intensifier tube as set forth in claim 5 wherein the respective opposing surfaces of the photocathode and the apertured electrode are contoured to maintain the shape of the first accelerating field substantially unchanged despite changes in intensity of the first accelerating field.
Claim 8
Independent Claim
70 words
A method of gating a photocathode of an image intensifier tube comprising the steps of biasing the photocathode at a predetermined potential, establishing an accelerating electrostatic field adjacent the photocathode and a decelerating electrostatic field of slightly greater intensity adjacent the accelerating field, and reducing the potential of the photocathode until the magnitude of intensity of the accelerating field is greater than the magnitude of intensity of the decelerating field.
Claim 9
Independent Claim
70 words
A method of gating a photocathode of an image intensifier tube comprising the steps of biasing the photocathode at a predetermined potential, establishing an accelerating electrostatic field adjacent the photocathode and a decelerating electrostatic field of slightly greater intensity adjacent the accelerating field, and reducing the potential of the photocathode until the magnitude of intensity of the accelerating field is greater than the magnitude of intensity of the decelerating field.
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) | 1976-05-14 | 1976-11-13 | 1977-05-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-05-14 | 1980-11-13 | 1981-05-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-05-14 | 1984-11-13 | 1985-05-15 | $7700.00 | Window Closed / Lapsed |