US3762284A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for grading the screen of a black surround color tube
Assignee: Zenith Electronics LLC
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Filing: 1972-04-28
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Granted: 1973-10-02
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Expires: 1992-04-28
Abstract
Abstract The process of screening a black surround on the faceplate of a rectangular color tube incorporating an automatic shading mechanism in the lighthouse varying the distribution of actinic energy over the sensitized coating on the faceplate for controlling the image size of the projected shadow mask apertures in a particular manner to produce images of decreasing area from the center to the edge of the faceplate with images of similar area located along a substantially rectangular locus centered with respect to the faceplate. The mechanism for controlling the exposure intensity over the faceplate comprises two pairs of movable plates for repetitively shading areas of the faceplate from the energy source.
Inventors
- 👤 Y Park
- 👤 R Pekosh
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 02:54
CPC Classifications
H; H01; H01J; H01J9/00; H01J9/20; H01J9/22; H01J9/227; H01J9/2271; H01J9/2272
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
141 words
A lighthouse for exposing the rectangular faceplate of a color cathode ray tube comprising: a housing having an open end a light source within said housing said housing being adapted to receive over said open end the rectangular face-plate Of a color cathode ray tube having a coating of photosensitized material on the inner surface thereof for exposure to said light source; a shading mechanism within said lighthouse interposed between said light source and said faceplate, said shading mechanism including; a set of movable shading plates, and means for moving said shading plates during exposure of the coating to said light source for shading portions of the coating from said light source to vary the energy distribution thereover in an intensity pattern decreasing from center to edge in accordance with a locus of substantially equal intensity rectangles centered about said faceplate.
Claim 2
Dependent Claim
141 words
A lighthouse for exposing the rectangular faceplate of a color cathode ray tube comprising: a housing having an open end a light source within said housing said housing being adapted to receive over said open end the rectangular face-plate Of a color cathode ray tube having a coating of photosensitized material on the inner surface thereof for exposure to said light source; a shading mechanism within said lighthouse interposed between said light source and said faceplate, said shading mechanism including; a set of movable shading plates, and means for moving said shading plates during exposure of the coating to said light source for shading portions of the coating from said light source to vary the energy distribution thereover in an intensity pattern decreasing from center to edge in accordance with a locus of substantially equal intensity rectangles centered about said faceplate.
Claim 3
Dependent Claim
63 words
A lighthouse as set forth in claim 1 wherein said set of shading plates comprise two opposed pairs of shading plates, a first opposed pair movable toward and away from each other along a path substantially parallel to the major axis of said faceplate and a second opposed pair similarly movable along a path substantially parallel to the minor axis of said faceplate.
Claim 4
Dependent Claim
33 words
A lighthouse as set forth in claim 2 wherein said shading plates include drive pins; and wherein said shading mechanism further includes cam surfaces cooperating with said drive pins for moving said plates.
Claim 5
Dependent Claim
30 words
A lighthouse as set forth in claim 3 wherein said cam surfaces are on a movable cam plate; and means moving said cam plate in an oscillatory manner during exposure.
Claim 6
Dependent Claim
37 words
A lighthouse as set forth in claim 4 wherein said cam surfaces include dwell portions for maintaining said first opposed pair of shading plates in a non-shading position during a portion of movement of said cam plate.
References Cited (Backward Citations)
US3259038A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-10-01 | 1977-04-02 | 1977-10-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-10-01 | 1981-04-02 | 1981-10-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-10-01 | 1985-04-02 | 1985-10-02 | $7700.00 | Window Closed / Lapsed |