US4682075A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Image display including improved light-absorbing matrix
Assignee: RCA Licensing Corp
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Filing: 1985-12-19
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Granted: 1987-07-21
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Expires: 2005-12-19
Abstract
Abstract An image display including a viewing screen comprising spaced elemental image areas and a light-absorbing matrix of partially-graphitized carbon black adjacent these areas. The matrix may be made by overcoating a stencil and stencil support with an aqueous slurry of the carbon black, drying the overcoating, and then removing the stencil and overlying overcoating.
Inventors
- 👤 Jordan R. Nelson
- 👤 William K. Wissing
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 20:55
CPC Classifications
H; H01; H01J; H01J29/00; H01J29/02; H01J29/10; H01J29/18; H01J29/30; H01J29/32; H01J29/327; H01J9/00; H01J9/20; H01J9/22; H01J9/227; H01J9/2278
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
33 words
In an image display including a viewing screen comprising spaced elemental image areas and a light-absorbing matrix adjacent said spaced areas, the improvement comprising said matrix consisting essentially of partially-graphitized carbon black particles.
Claim 2
Dependent Claim
33 words
In an image display including a viewing screen comprising spaced elemental image areas and a light-absorbing matrix adjacent said spaced areas, the improvement comprising said matrix consisting essentially of partially-graphitized carbon black particles.
Claim 3
Dependent Claim
48 words
The display defined in claim 1 wherein a dry mass of said particles exhibits a TGA (thermogravimetric analysis) curve that is between and displaced from the TGA curves both of ground natural graphite platelets passing a 200-mesh screen and of colloidal graphite particles about 0.5 micron in size.
Claim 4
Dependent Claim
31 words
The display defined in claim 2 wherein said curves are produced at a heating rate of 5° C./min., and said displacements are more than 50° C. and less than 200° C.
Claim 5
Dependent Claim
29 words
The display defined in claim 1 wherein a layer of said particles has a direct specular reflection of about 4 foot-lamberts and a diffuse reflection of about 0.8 foot-lamberts.
Claim 6
Dependent Claim
27 words
The display defined in claim 1 wherein said partially-graphitized carbon black is prepared by heating furnace black at temperatures above 1500° C. for at least 4 hours.
Claim 7
Dependent Claim
37 words
The display defined in claim 1 wherein said viewing screen is attached to the inner surface of the viewing window of a multi-color cathode-ray tube, and each of said elemental image areas is filled with cathodoluminescent material.
Claim 8
Dependent Claim
30 words
The display defined in claim 6 wherein said tube is a color television picture tube and said elemental areas is an ordered array of red-emitting, green-emitting and blue-emitting cathodoluminescent material.
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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) | 1990-07-20 | 1991-01-19 | 1991-07-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-07-20 | 1995-01-19 | 1995-07-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-07-20 | 1999-01-19 | 1999-07-21 | $7700.00 | Window Closed / Lapsed |