US4184745A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Translucent screen
Assignee: Polaroid Corp
•
Filing: 1978-03-08
•
Granted: 1980-01-22
•
Expires: 1998-03-08
Abstract
Abstract Translucent screens are provided comprising a dispersion of starch particles in a continuous polymeric phase.
Inventors
- 👤 Edwin H. Land
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 02:08
CPC Classifications
G; G03; G03B; G03B21/00; G03B21/54; G03B21/56; G03B21/60; G03B21/62; C; C08; C08L; C08L1/00; C08L1/08
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
38 words
A translucent screen consisting essentially of a dispersion of rice starch particles as a discontinuous phase in a polymeric continuous phase, said starch particles having non-planar and non-parallel surfaces and having overall diameters not exceeding about 15 microns.
Claim 2
Dependent Claim
38 words
A translucent screen consisting essentially of a dispersion of rice starch particles as a discontinuous phase in a polymeric continuous phase, said starch particles having non-planar and non-parallel surfaces and having overall diameters not exceeding about 15 microns.
Claim 3
Dependent Claim
33 words
A translucent screen as defined in claim 1 wherein the difference between the index of refraction of said polymeric continuous phase and the index of refraction of said starch particles is about 0.04.
Claim 4
Dependent Claim
21 words
A translucent screen as defined in claim 1 wherein said starch particles have a diameter of about 2 to 8 microns.
Claim 5
Dependent Claim
16 words
A translucent screen as defined in claim 1 wherein said polymeric continuous phase is ethyl cellulose.
Claim 6
Dependent Claim
16 words
A translucent screen as defined in claim 1 wherein said polymeric continuous phase is cellulose acetate.
Claim 7
Dependent Claim
16 words
A translucent screen as defined in claim 1 wherein said polymeric continuous phase is polymethyl methacrylate.
Claim 8
Dependent Claim
33 words
A translucent screen as defined in claim 1 wherein said starch particles are rice starch particles having a diameter of about 2 to 8 microns and said polymeric continuous phase is ethyl cellulose.
Claim 9
Dependent Claim
19 words
A translucent screen as defined in claim 1, wherein the surfaces of said screen are substantially flat and parallel.
Claim 10
Dependent Claim
19 words
A translucent screen as defined in claim 8 wherein at least one of said surfaces carries an antireflection coating.
Claim 11
Dependent Claim
15 words
A translucent screen as defined in claim 9 having the configuration of a Fresnel lens.
Claim 12
Dependent Claim
16 words
A translucent screen as defined in claim 1 including a small quantity of a light-absorbing material.
Claim 13
Dependent Claim
15 words
A translucent screen as defined in claim 11 wherein said light-absorbing material is carbon black.
References Cited (Backward Citations)
US3609000A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-01-21 | 1983-07-23 | 1984-01-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-01-21 | 1987-07-23 | 1988-01-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-01-21 | 1991-07-23 | 1992-01-22 | $7700.00 | Window Closed / Lapsed |