US3591253A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Rear projection screen
Assignee: Eastman Kodak Co
•
Filing: 1969-07-02
•
Granted: 1971-07-06
•
Expires: 1989-07-02
Abstract
Abstract A rear projection screen comprising a sheet of polymeric material, the sheet being of sufficient thickness to be selfsupporting and having improved optical characteristics. More specifically, the sheet of material is preferably made from the polyolefins, for example, polyethylene or polypropylene, that has been prepared in such a way so as to have a generally crystalline structure.
Inventors
- 👤 James J De Palma
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 02:40
CPC Classifications
G; G03; G03B; G03B21/00; G03B21/54; G03B21/56; G03B21/60; G03B21/62
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
33 words
A rear projection screen comprising: a sheet of polymeric material consisting essentially of a single polyolefin; said material being of generally crystalline structure and generally comprising randomly oriented anisotropic domains of various sizes.
Claim 2
Dependent Claim
33 words
A rear projection screen comprising: a sheet of polymeric material consisting essentially of a single polyolefin; said material being of generally crystalline structure and generally comprising randomly oriented anisotropic domains of various sizes.
Claim 3
Dependent Claim
17 words
A rear projection screen in accordance with claim 1 wherein each of said domains comprises a spherulite.
Claim 4
Dependent Claim
21 words
A rear projection screen in accordance with claim 2 wherein said spherulites comprise at least 60 percent of the screen mass.
Claim 5
Dependent Claim
28 words
A rear projection screen in accordance with claim 2 wherein a major share of said spherulites have an average diameter of from about 5 to about 20 microns.
Claim 6
Dependent Claim
16 words
A rear projection screen in accordance with claim 1 in which said polymeric material is polyeThylene.
Claim 7
Dependent Claim
16 words
A rear projection screen in accordance with claim 1 in which said polymeric material is polypropylene.
Claim 8
Dependent Claim
21 words
A rear projection screen in accordance with claim 1 wherein said sheet has a thickness of about 20 to 80 mils.
Claim 9
Dependent Claim
39 words
A rear projection screen comprising: a sheet of material consisting essentially of polyethylene having a thickness of about 20 to 80 miles; said material being of generally crystalline structure and generally comprising randomly oriented anisotropic spherulites of various sizes.
Claim 10
Dependent Claim
39 words
A rear projection screen comprising: a sheet of material consisting essentially of polyethylene having a thickness of about 20 to 80 miles; said material being of generally crystalline structure and generally comprising randomly oriented anisotropic spherulites of various sizes.
Claim 11
Dependent Claim
25 words
A rear projection screen in accordance with claim 9 wherein said spherulites comprise from about 60 percent to about 90 percent of the screen mass.
Claim 12
Dependent Claim
28 words
A rear projection screen in accordance with claim 8 wherein a major share of said spherulites have an average diameter of from about 5 to about 20 microns.
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) | 1974-07-05 | 1975-01-04 | 1975-07-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-07-05 | 1979-01-04 | 1979-07-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-07-05 | 1983-01-04 | 1983-07-06 | $7700.00 | Window Closed / Lapsed |