US3864595A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Automatic brightness control for gated micro-channel plate intensifier
Assignee: Westinghouse Electric Corp
•
Filing: 1973-04-19
•
Granted: 1975-02-04
•
Expires: 1993-04-19
Abstract
Abstract An image intensifier tube is described as including a photocathode element for converting an incident radiation image into a corresponding electron image, a micro-channel plate for multiplying the electron image, and a phosphorous screen for converting the multiplied electron image into a corresponding radiation image to be viewed. The electron image may be turned ''''on'''' and ''''off'''' by selectively applying a gating signal to the photocathode element. A potential applied between the first and second electrodes of the micro-channel plate is varied in accordance with the current absorbed at the second electrode to control the degree of electron multiplication and to prevent saturation of the phosphorous screen. In an illustrative embodiment, a variable potential source coupled to the electrodes of the micro-channel plate, includes a variable oscillator responsive to the current derived from the second electrode and an AC/DC converter for applying a DC potential whose magnitude corresponds to the variable frequency of this oscillator. Significantly, the supply source for the phosphorous screen includes first and second sections, the first section including an AC/DC converter connected to the aforementioned variable oscillator, for providing a variable potential between the second electrode of the micro-channel plate and the phosphorous screen, dependent upon the variable potential applied between the electrodes of the micro-channel plate. The second section includes illustratively a fixed oscillator and a third AC/DC converter whose output is connected to the phosphorous screen.
Inventors
- 👤 George N Lawrence
- 👤 Melvin C Seid
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 05:45
CPC Classifications
H; H01; H01J; H01J31/00; H01J31/08; H01J31/50; H04; H04N; H04N23/00; H04N23/70; H04N23/75; H01J2231/00; H01J2231/50; H01J2231/50005; H01J2231/5001; H01J2231/50057; H01J2231/50068; H01J2231/501; H01J2231/5013; H01J2231/5016
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
176 words
An image intensifier device comprising: a. photocathode means responsive to incident radiation image for generating a corresponding electron image; b. electron multiplying means for multiplying the electron image derived from said photocathode means, said electron multiplying means including an input electrode and an output electrode; c. display means responsive to the multiplied electron image for providing a visual radiation image corresponding thereto; d. gating means interconnected between said input electrode and said photocathode means for selectively permitting the flow of electrons from said photocathode means to be directed onto said electron multiplying means; e. brightness control means responsive to the current of the multiplied electron image directed onto said display means for varying the potential applied between said input electrode and said output electrode to prevent substantially the saturation of said display means; and f. display supply means responsive to the variable voltage applied between said input and output electrodes for applying a selectively variable voltage to said display means such that a substantially constant potential is maintained between said output electrode and said display means.
Claim 2
Dependent Claim
176 words
An image intensifier device comprising: a. photocathode means responsive to incident radiation image for generating a corresponding electron image; b. electron multiplying means for multiplying the electron image derived from said photocathode means, said electron multiplying means including an input electrode and an output electrode; c. display means responsive to the multiplied electron image for providing a visual radiation image corresponding thereto; d. gating means interconnected between said input electrode and said photocathode means for selectively permitting the flow of electrons from said photocathode means to be directed onto said electron multiplying means; e. brightness control means responsive to the current of the multiplied electron image directed onto said display means for varying the potential applied between said input electrode and said output electrode to prevent substantially the saturation of said display means; and f. display supply means responsive to the variable voltage applied between said input and output electrodes for applying a selectively variable voltage to said display means such that a substantially constant potential is maintained between said output electrode and said display means.
Claim 3
Dependent Claim
44 words
An image intensifier device as claimed in claim 1, wherein said electron multiplying means comprises means for defining a plurality of passages therethrough between said input electrode and said output electrode, each of said passages having a surface of a secondary electron emissive material.
Claim 4
Dependent Claim
243 words
An image intensifier device comprising: a. photocathode means responsive to incident radiation image for generating a corresponding electron image; b. electron multiplying means for multiplying the electron image derived from said photocathode means, said electron multiplying means including an input electrode and an output electrode; c. display means responsive to the multiplied electron image for providing a visual radiation image corresponding thereto; d. gating means interconnected between said input electrode and said photocathode means for selectively permitting the flow of electrons from said photocathode means to be directed onto said electron multiplying means; e. brightness control means responsive to the current of the multiplied electron image directed onto said display means for varying the potential applied between said input electrode and said output electrode to prevent substantially the saturation of said display means; and f. display supply means responsive to the variable voltage applied between said input and output electrodes for applying a selectively variable voltage to said display means such that a substantially constant potential is maintained between said output electrode and said display means, said display supply means including a first part responsive to the variable potential applied between said input and output electrodes for producing a first signal corresponding thereto, and a second part for producing a second signal of substantially fixed magnitude, and means for applying the first and second voltages to said display means to provide a substantially constant potential between said output electrode and said display means.
Claim 5
Dependent Claim
243 words
An image intensifier device comprising: a. photocathode means responsive to incident radiation image for generating a corresponding electron image; b. electron multiplying means for multiplying the electron image derived from said photocathode means, said electron multiplying means including an input electrode and an output electrode; c. display means responsive to the multiplied electron image for providing a visual radiation image corresponding thereto; d. gating means interconnected between said input electrode and said photocathode means for selectively permitting the flow of electrons from said photocathode means to be directed onto said electron multiplying means; e. brightness control means responsive to the current of the multiplied electron image directed onto said display means for varying the potential applied between said input electrode and said output electrode to prevent substantially the saturation of said display means; and f. display supply means responsive to the variable voltage applied between said input and output electrodes for applying a selectively variable voltage to said display means such that a substantially constant potential is maintained between said output electrode and said display means, said display supply means including a first part responsive to the variable potential applied between said input and output electrodes for producing a first signal corresponding thereto, and a second part for producing a second signal of substantially fixed magnitude, and means for applying the first and second voltages to said display means to provide a substantially constant potential between said output electrode and said display means.
Claim 6
Dependent Claim
98 words
An image intensifier device as claimed in claim 3, wherein said brightness control means includes a sensing resistor responsive to the current level developed in said display means in response to the incident multiplied electron image for providing a Signal indicative thereof; a first, variable oscillator responsive to the aforementioned signal for generating an output signal whose frequency corresponds thereto; and a first AC/DC converter circuit responsive to the output signal of said first, variable oscillator for applying a voltage between said input electrode and said output electrode varying inversely to the signal derived from said sensing resistor.
Claim 7
Dependent Claim
49 words
An image intensifier device as claimed in claim 4, wherein said display supply means includes a second AC/DC converter responsive to the output signal of said first, variable oscillator for providing a DC output signal corresponding to the output signal applied between said input electrode and said output electrode.
Claim 8
Dependent Claim
95 words
An image intensifier device as claimed in claim 5, wherein said display supply means further includes a second, fixed oscillator for providing an output signal of substantially fixed frequency and a third AC/DC converter responsive to the output signal of said second, fixed oscillator for providing a DC output signal of substantially fixed magnitude, and means for summing the output signals of said second AC/DC converter and said third AC/DC converter and for applying the summed signal to said display means to provide a substantially constant voltage between said output electrode and said display means.
Claim 9
Dependent Claim
26 words
Apparatus as claimed in claim 4, wherein said first electrode is connected to ground and said second electrode is coupled through said sensing resistor to ground.
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) | 1978-02-03 | 1978-08-05 | 1979-02-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-02-03 | 1982-08-05 | 1983-02-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-02-03 | 1986-08-05 | 1987-02-04 | $7700.00 | Window Closed / Lapsed |