US3721752A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Image pickup tube
Assignee: Sony Corp
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Filing: 1971-12-21
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Granted: 1973-03-20
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Expires: 1991-12-21
Abstract
Abstract In an image pickup tube for a color television camera having a photoconductive layer for the conversion of images projected thereon into an electrical output and onto which a color separated image of an object to be reproduced is projected through a color filter which is part of the tube or separate therefrom and a pair of indexing electrodes disposed in close proximity to the photoconductive layer to electrically produce an index image on such layer in response to the application of different voltages to the indexing electrodes; two photovoltaic cells are included in the image pickup tube and electrically connected in parallel with each other between the indexing electrodes with their polarities reversed, and the photovoltaic cells are alternately activated by radiant energy originating outside the tube to provide the different voltages for producing the index image so that the electrical output is a composite signal containing a color video signal corresponding to the color separated image and a balanced index signal corresponding to the index image and by which individual color component signals may be separated from the color video signal. The electrical output is preferably derived at a junction between a pair of seriesconnected resistors also connected between the indexing electrodes; and a biasing voltage is also applied to the indexing electrodes by way of that junction.
Inventors
- 👤 T Kakizaki
- 👤 Y Kubota
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 13:09
CPC Classifications
H; H01; H01J; H01J29/00; H04; H04N; H04N9/00; H04N9/01
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
123 words
An image pickup tube comprising a photoconductive layer for the conversion of images projected thereon into an electrical output,, a pair of indexing electrodes disposed in close proximity to said photoconductive layer for electrically forming an index image on said layer to be included as an index signal in said electrical output in response to the application of different voltages to said indexing electrodes, a pair of photovoltaic cells connected in parallel with each other between said indexing electrodes with the polarities of said photovoltaic cells being reversed relative to each other, and radiant energy sources associated with said photovoltaic cells, respectively, and being alternately energized for alternately activating the respective photovoltaic cells and thereby applying said different voltages to said indexing electrodes.
Claim 2
Dependent Claim
123 words
An image pickup tube comprising a photoconductive layer for the conversion of images projected thereon into an electrical output,, a pair of indexing electrodes disposed in close proximity to said photoconductive layer for electrically forming an index image on said layer to be included as an index signal in said electrical output in response to the application of different voltages to said indexing electrodes, a pair of photovoltaic cells connected in parallel with each other between said indexing electrodes with the polarities of said photovoltaic cells being reversed relative to each other, and radiant energy sources associated with said photovoltaic cells, respectively, and being alternately energized for alternately activating the respective photovoltaic cells and thereby applying said different voltages to said indexing electrodes.
Claim 3
Dependent Claim
34 words
An image pickup tube according to claim 1, further comprising a pair of series-connected resistors also connected between said indexing electrodes and providing a junction between said resistors at which said output is derived.
Claim 4
Dependent Claim
19 words
An image pickup tube according to claim 2, further comprising means for applyiNg a bias voltage to said junction.
Claim 5
Dependent Claim
53 words
An image pickup tube according to claim 1, further comprising filter means for forming a color separated image of an object to be reproduced on said layer so that said electrical output is a composite signal containing a color video signal corresponding to said color separated image in addition to said index signal.
Claim 6
Dependent Claim
44 words
An image pickup tube according to claim 4, further comprising circuit means for separating aid color video signal and said index signal from said composite signal, and means controlled by said index signal for separating individual color component signals from said color video signal.
Claim 7
Dependent Claim
36 words
An image pickup tube according to claim 4, in which said photoconductive layer, indexing electrodes, photovoltaic cells and filter means are joined together in a unitary structure constituting a faceplate assembly of the image pickup tube.
Claim 8
Dependent Claim
34 words
An image pickup tube according to claim 1, in which said photoconductive layer, indexing electrodes and photovoltaic cells are joined together in a unitary structure constituting a faceplate assembly of the image pickup tube.
Claim 9
Dependent Claim
31 words
An image pickup tube according to claim 7, in which said radiant energy sources are at the exterior of said faceplate assembly for emitting light rays to energize said photovoltaic cells.
Claim 10
Dependent Claim
33 words
An image pickup tube according to claim 8, in which said light rays emitted by said radiant energy sources are within a portion of the spectrum to which said photoconductive layer is insensitive.
Claim 11
Dependent Claim
152 words
An image pickup tube according to claim 8, further comprising means producing an electron beam which scans said photoconductive layer with a predetermined scanning period; and in which said indexing electrodes each include a plurality of elongated parallel elements extending at right angles to the direction of scanning of said layer by said beam with said elements of one of said indexing electrodes being interleaved with said elements of the other of said indexing electrodes so that said index signal is represented by an alternating voltage in said output, and said radiant energy sources are alternately energized by circuit means including an alternating signal source synchronized with the scanning pf said beam and connected with said radiant energy sources to cause said photovoltaic cells to alternate said different voltages applied to said indexing electrodes in successive scanning periods and thereby reverse the phase of said index signal in said successive scanning periods.
Claim 12
Dependent Claim
27 words
An image pickup tube according to claim 8, in which said radiant energy source includes at least one luminescent diode which, when energized, emits said lights rays.
Claim 13
Dependent Claim
91 words
An image pickup tube according to claim 8, further comprising a tube envelope having said faceplate assembly disposed at one end, a conductive ring extending around said end of the tube envelope and around the periphery of said faceplate assembly, an electrically conductive sealing member interposed between said ring and said faceplate assembly and tube envelope for hermetically sealing said end of the tube, and conductive means on said faceplate assembly between said sealing member and said index electrodes for applying a bias voltage to the latter from said conductive ring.
Claim 14
Dependent Claim
26 words
An image pickup tube according to claim 12, in which said conductive means further defines a pair of series-connected resistors also connected between said indexing electrodes.
Claim 15
Dependent Claim
40 words
An image pickup tube according to claim 13, in which said indexing electrodes are in contact with said photoconductive layer which has a high resistance so that said electrical output is obtained at said conductive ring from between said resistors.
References Cited (Backward Citations)
US3575548A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-03-19 | 1976-09-18 | 1977-03-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-03-19 | 1980-09-18 | 1981-03-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-03-19 | 1984-09-18 | 1985-03-20 | $7700.00 | Window Closed / Lapsed |