US3628076A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Photoconductive screen deriving light thorugh light conductor from tube filament
Assignee: US Philips Corp
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Filing: 1969-12-17
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Granted: 1971-12-14
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Expires: 1989-12-17
Abstract
Abstract A television camera tube of the Vidicon type in which a photoconductive screen at one end of an evacuated envelope receives an image of a scene to be televised and is scanned by an electron beam. An auxiliary light source is provided for uniformly illuminating the screen and a light conductor, at least partly outside the path of illumination from the scene, conducts light from the auxiliary source to the screen.
Inventors
- 👤 Willem Paul Weijland
- 👤 Hans Georg Gerlach
- 👤 Antonius Joannes Maria Va Beld
- 👤 Louis Maarten Swart
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 23:55
CPC Classifications
H; H01; H01J; H01J29/00; H01J29/86; H01J29/89; H01J29/892; H01J31/00; H01J31/08; H01J31/26; H01J31/28; H01J31/34; H01J31/38; H01J2229/00; H01J2229/89; H01J2229/8926
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
157 words
A television camera tube comprising an evacuated envelope having a transparent wall portion, a photoconductive screen having one surface facing said transparent wall portion for receiving an image of a scene, means to scan the opposite side of said screen with an electron beam thereby generating an electrical current corresponding to light variations in said scene, said scan means including an electron gun for generating an electron beam remote from the screen and means to deflect the electron beam before it impinges on the screen, means for uniformly illuminating said screen including a filament and at least one light conductor for conducting light by multiple internal reflection from filament to a point opposite the side of the screen struck by the electron beam for providing bias illumination over substantially the entire surface of the screen struck by the electron beam, at least a portion of said light conductor lying outside the path of illumination from the scene.
Claim 2
Dependent Claim
157 words
A television camera tube comprising an evacuated envelope having a transparent wall portion, a photoconductive screen having one surface facing said transparent wall portion for receiving an image of a scene, means to scan the opposite side of said screen with an electron beam thereby generating an electrical current corresponding to light variations in said scene, said scan means including an electron gun for generating an electron beam remote from the screen and means to deflect the electron beam before it impinges on the screen, means for uniformly illuminating said screen including a filament and at least one light conductor for conducting light by multiple internal reflection from filament to a point opposite the side of the screen struck by the electron beam for providing bias illumination over substantially the entire surface of the screen struck by the electron beam, at least a portion of said light conductor lying outside the path of illumination from the scene.
Claim 3
Dependent Claim
26 words
A camera tube as claimed in claim 1 wherein the light conductor is shaped as a rod and is bent towards the filament at one end.
Claim 4
Dependent Claim
22 words
A camera tube as claimed in claim 1 wherein the light-conductor comprises a bundle of parallel glass wires which are adhered together.
Claim 5
Dependent Claim
56 words
A camera tube as claimed in claim 1 wherein the envelope wall is the light conductor and at least the edges of the transparent wall portion are rounded off and are covered with a light reflecting layer so that light of the filament of the cathode is guided to the photoconductive screen through the envelope wall.
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) | 1974-12-13 | 1975-06-14 | 1975-12-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-12-13 | 1979-06-14 | 1979-12-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-12-13 | 1983-06-14 | 1983-12-14 | $7700.00 | Window Closed / Lapsed |