Patent US3631252A successfully refreshed from Google Patents.
US3631252A
Expired / Lapsed
US
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Image control apparatus utilizing the convolution of phosphors
Assignee: United States Department of the Air Force
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Filing: 1970-03-24
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Granted: 1971-12-28
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Expires: 1990-03-24
Abstract
Abstract By using the delay time incurred in image reproduction brought about by the convolution action of the phosphor in image converter tubes, time is obtained in which to turn off the reproduction of the image or to lower the reproduction intensity so that the intensity of the oncoming image will not damage a camera tube or overexpose photographic film. Conversely, time may be achieved in which to turn the image on, likewise to a camera tube or photographic film, or reproducing or recording a fastacting phenomenon such as a lightning flash or bomb burst without the necessity of wasteful continuous exposure in order to ''''catch'''' the desired image.
Inventors
- 👤 Radames K H Gebel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 19:57
CPC Classifications
H; H01; H01J; H01J31/00; H01J31/08; H01J31/50; H01J31/501; H01J31/502; H01J2231/00; H01J2231/50; H01J2231/50057; H01J2231/50089
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
240 words
Image control apparatus for protecting an image transducer from light of an intensity greater than a predetermined value, comprising: a. means for receiving light energy from a field of view and providing an image forming light beam; b. a first beam splitter for dividing the image foRming light beam into a first beam and second beam; c. a photocell for sensing the light intensity of the first beam; d. threshold means including the said predetermined value of intensity cooperating with the said photocell for providing a signal when the intensity of the said image forming light beam exceeds the said predetermined value of intensity; e. a second beam splitter for dividing the said second beam into a third and fourth beam; f. a light shutter interposed between the said first and second beam splitters intercepting the said second beam; g. shutter control means responsive to the said signal from the threshold means for actuating said light shutter; h. a multiplier phototube for sensing the light intensity of the said third light beam; i. an image intensifier having a photocathode for receiving the said fourth light beam and a phosphor for providing an image output to the said protected image transducer; and j. output intensity control means responsive to the said multiplier phototube, cooperating with the said image intensifier for controlling the output image intensity level from the phosphor to a level below that causing damage to the said image transducer.
Claim 2
Dependent Claim
240 words
Image control apparatus for protecting an image transducer from light of an intensity greater than a predetermined value, comprising: a. means for receiving light energy from a field of view and providing an image forming light beam; b. a first beam splitter for dividing the image foRming light beam into a first beam and second beam; c. a photocell for sensing the light intensity of the first beam; d. threshold means including the said predetermined value of intensity cooperating with the said photocell for providing a signal when the intensity of the said image forming light beam exceeds the said predetermined value of intensity; e. a second beam splitter for dividing the said second beam into a third and fourth beam; f. a light shutter interposed between the said first and second beam splitters intercepting the said second beam; g. shutter control means responsive to the said signal from the threshold means for actuating said light shutter; h. a multiplier phototube for sensing the light intensity of the said third light beam; i. an image intensifier having a photocathode for receiving the said fourth light beam and a phosphor for providing an image output to the said protected image transducer; and j. output intensity control means responsive to the said multiplier phototube, cooperating with the said image intensifier for controlling the output image intensity level from the phosphor to a level below that causing damage to the said image transducer.
Claim 3
Dependent Claim
22 words
The image control apparatus as claimed in claim 1 wherein the said image intensifier comprises a plurality of cascaded image intensifier tubes.
Claim 4
Dependent Claim
248 words
Image control apparatus for providing a relatively constant image intensity to an image transducer comprising: a. an image intensifier having a photocathode for receiving an optical image, a phosphor for providing an image output, determined convolution light reproduction characteristics, and an intensity control electrode; b. means receiving light directly from the same field of view as the said image intensifier for providing a control signal responsive to the average spacial intensity of the optical image received by the image intensifier; c. a radiofrequency oscillator; d. a modulator receiving the said control signal and the output of the said radiofrequency oscillator, the said modulator having a predetermined threshold of operation corresponding to a determined value of light intensity which the said control signal must exceed in order for the modulator to provide an output signal, and the magnitude of the said output signal of the modulator then being responsive to the amount the said control signal exceeds the threshold; and e. a voltage controller including a rectifier and a circuit that has charge and discharge characteristics that substantially match the said convolution light reproduction characteristics of the said image intensifier, the said voltage controller receiving the said output signal of the modulator and providing a signal to the said intensity control electrode of the image intensifier whereby the image output intensity from the said image intensifier to the said image transducer is essentially uniform with varying optical image input intensities that exceed the said determined value of light intensity.
Claim 5
Dependent Claim
248 words
Image control apparatus for providing a relatively constant image intensity to an image transducer comprising: a. an image intensifier having a photocathode for receiving an optical image, a phosphor for providing an image output, determined convolution light reproduction characteristics, and an intensity control electrode; b. means receiving light directly from the same field of view as the said image intensifier for providing a control signal responsive to the average spacial intensity of the optical image received by the image intensifier; c. a radiofrequency oscillator; d. a modulator receiving the said control signal and the output of the said radiofrequency oscillator, the said modulator having a predetermined threshold of operation corresponding to a determined value of light intensity which the said control signal must exceed in order for the modulator to provide an output signal, and the magnitude of the said output signal of the modulator then being responsive to the amount the said control signal exceeds the threshold; and e. a voltage controller including a rectifier and a circuit that has charge and discharge characteristics that substantially match the said convolution light reproduction characteristics of the said image intensifier, the said voltage controller receiving the said output signal of the modulator and providing a signal to the said intensity control electrode of the image intensifier whereby the image output intensity from the said image intensifier to the said image transducer is essentially uniform with varying optical image input intensities that exceed the said determined value of light intensity.
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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) | 1974-12-27 | 1975-06-28 | 1975-12-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-12-27 | 1979-06-28 | 1979-12-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-12-27 | 1983-06-28 | 1983-12-28 | $7700.00 | Window Closed / Lapsed |