US3700804A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of improving cathodochromic sensitivity
Assignee: RCA Licensing Corp
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Filing: 1970-10-08
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Granted: 1972-10-24
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Expires: 1990-10-08
Abstract
Abstract Method of operating a display tube comprising a screen including a cathodochromic material. The method comprises steps of heating the cathodochromic material to a temperature below the total erase temperature and writing information on the cathodochromic material (by electron impingement thereon) while the heating is continued. Heating can be done by the writing electron beam and/or supplemental heating means.
Inventors
- 👤 Philip Michael Heyman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 16:19
CPC Classifications
H; H01; H01J; H01J29/00; H01J29/02; H01J29/10; H01J29/14
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
100 words
A method of operating a display tube including a screen comprising a layer of cathodochromic material, said cathodochromic material being characterized by the generation of color centers therein in response to electron impingement thereon and the elimination of said color centers by exposure of said cathodochromic material to a total erase temperature, said method comprising: a. writing information on said cathodochromic material by directing an electron beam thereon; and b. heating said cathodochromic material to an elevated temperature above room temperature and below said total erase temperAture during said writing operation using a heating means independent of said electron beam.
Claim 2
Independent Claim
100 words
A method of operating a display tube including a screen comprising a layer of cathodochromic material, said cathodochromic material being characterized by the generation of color centers therein in response to electron impingement thereon and the elimination of said color centers by exposure of said cathodochromic material to a total erase temperature, said method comprising: a. writing information on said cathodochromic material by directing an electron beam thereon; and b. heating said cathodochromic material to an elevated temperature above room temperature and below said total erase temperAture during said writing operation using a heating means independent of said electron beam.
Claim 3
Dependent Claim
19 words
The method defined in claim 1, wherein said information is read, said heating being continued during said reading operation.
Claim 4
Dependent Claim
38 words
The method defined in claim 1, wherein said cathodochromic material is sodalite and said heating is executed by applying to said cathodochromic material a total power up to about 1.5 watts per square inch of said cathodochromic layer.
Claim 5
Dependent Claim
24 words
The method defined in claim 1, wherein said cathodochromic material is sodalite and said elevated temperature is between room temperature and about 200* C.
Claim 6
Dependent Claim
19 words
The method defined in claim 1, wherein said heating is executed at least in part by said electron beam.
Claim 7
Dependent Claim
36 words
The method defined in claim 1, wherein said cathodochromic material is further characterized by an initial increase in the sensitivity thereof with increasing temperature and a subsequent decrease in said sensitivity with further increase in temperature.
Claim 8
Dependent Claim
28 words
The method defined in claim 1, wherein said heating is executed by passing electrical current through a electrically conducting element in heat transfer relationship with said cathodochromic material.
Claim 9
Dependent Claim
19 words
The method defined in claim 1, wherein said heating is executed by projecting infra-red radiation on said cathodochromic material.
References Cited (Backward Citations)
US2836753A
Cited
US2755407A
Cited
US3253497A
Cited
US3252374A
Cited
US3365577A
Cited
US3401262A
Cited
US3438022A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-10-24 | 1976-04-24 | 1976-10-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-10-24 | 1980-04-24 | 1980-10-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-10-24 | 1984-04-24 | 1984-10-24 | $7700.00 | Window Closed / Lapsed |