US3964822A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Projection screen and process for production thereof
Assignee: Mitsui Chemicals Inc
•
Filing: 1974-10-07
•
Granted: 1976-06-22
•
Expires: 1994-10-07
Abstract
Abstract A projection screen includes a substrate having a metallic aluminum surface and a transparent film overlay. The metallic aluminum surface is provided with a pattern of directional irregularities and a pattern of craters. The projection screen is produced by subjecting an aluminum surface to a mechanical surface treatment to form a dense pattern of fine irregularities, etching the treated surface to form a crater pattern thereon and coating the resulting surface with a protective transparent film.
Inventors
- 👤 Akira Yamashita
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 16:21
CPC Classifications
G; G03; G03B; G03B21/00; G03B21/54; G03B21/56; G03B21/60
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
68 words
A projection screen which comprises: a substrate having a metallic aluminum surface, a transparent film overlaying said metallic aluminum surface, said metallic aluminum surface having a fine, dense pattern of directional irregularities and a pattern of nondirectional craters provided thereon; and said transparent film having a thickness of from 0.5 to 10 microns and a roughness expressed as a maximum height (R max) of from 0.2S to 25S.
Claim 2
Dependent Claim
68 words
A projection screen which comprises: a substrate having a metallic aluminum surface, a transparent film overlaying said metallic aluminum surface, said metallic aluminum surface having a fine, dense pattern of directional irregularities and a pattern of nondirectional craters provided thereon; and said transparent film having a thickness of from 0.5 to 10 microns and a roughness expressed as a maximum height (R max) of from 0.2S to 25S.
Claim 3
Dependent Claim
17 words
A projection screen according to claim 1 in which the transparent film comprises an aluminum oxide film.
Claim 4
Dependent Claim
16 words
A projection screen according to claim 1 in which the transparent film comprises a plastic film.
Claim 5
Dependent Claim
70 words
A process for producing a projection screen which comprises the steps of: applying a mechanical substantially unidirectional abrasive surface treatment to a metallic aluminum surface of a substrate to form a fine, dense pattern of directional irregularities; etching the treated surface thus obtained to form a nondirectional crater pattern thereon; and forming a transparent film on the treated, etched surface to protect the surface without substantially decreasing the reflectivity thereof.
Claim 6
Dependent Claim
70 words
A process for producing a projection screen which comprises the steps of: applying a mechanical substantially unidirectional abrasive surface treatment to a metallic aluminum surface of a substrate to form a fine, dense pattern of directional irregularities; etching the treated surface thus obtained to form a nondirectional crater pattern thereon; and forming a transparent film on the treated, etched surface to protect the surface without substantially decreasing the reflectivity thereof.
Claim 7
Dependent Claim
25 words
A process according to claim 4 in which the transparent film is formed by anodizing the treated, etched surface to form an aluminum oxide film.
Claim 8
Dependent Claim
26 words
A process according to claim 4 in which the transparent film is formed by applying plastic to the treated, etched surface to form a plastic film.
References Cited (Backward Citations)
US3507548A
Cited
US3573074A
Cited
US3653740A
Cited
US3811750A
Cited
US3851950A
Cited
US3844644A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-06-22 | 1979-12-22 | 1980-06-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-06-22 | 1983-12-22 | 1984-06-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-06-22 | 1987-12-22 | 1988-06-22 | $7700.00 | Window Closed / Lapsed |