Patent US5298199A successfully refreshed from Google Patents.
US5298199A
Expired / Lapsed
US
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Optical birefringence compensator adapted for LCD
Assignee: Stanley Electric Co Ltd
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Filing: 1991-10-11
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Granted: 1994-03-29
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Expires: 2011-10-11
Abstract
Abstract Ionomer resin sheet is stretched in one direction in the plane of sheet to give uniaxial anisotropy, and then heated above the melting point under pressure to cause relaxation of the anisotropy. After cooling, a sheet of biaxial anisotropy is obtained. The degree of anisotropy depends on the initial stretching, heating temperature, heating time and pressure.
Inventors
- 👤 Shinichi Hirose
- 👤 Jean F. Clerc
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 20:48
CPC Classifications
G; G02; G02B; G02B5/00; G02B5/30; G02B5/3083; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/133; G02F1/1333; G02F1/1335; G02F1/13363; G02F1/133634; Y; Y10; Y10T; Y10T428/00; Y10T428/31504; Y10T428/31855; Y10T428/31935
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
73 words
A method of producing a biaxial optical compensator, comprising the successive steps of: (a) stretching an ion-containing polymer sheet to impart optical anisotropy thereto; (b) sandwiching the thus stretched ion-containing polymer sheet between two substrates while maintaining the optical anisotropy; (c) heating the ion containing polymer sheet; (d) discontinuing heating before the stretched ion-containing polymer sheet becomes optically isotropic; and thereafter (e) cooling the ion-containing polymer sheet thereby obtaining an optically biaxial sheet.
Claim 2
Independent Claim
73 words
A method of producing a biaxial optical compensator, comprising the successive steps of: (a) stretching an ion-containing polymer sheet to impart optical anisotropy thereto; (b) sandwiching the thus stretched ion-containing polymer sheet between two substrates while maintaining the optical anisotropy; (c) heating the ion containing polymer sheet; (d) discontinuing heating before the stretched ion-containing polymer sheet becomes optically isotropic; and thereafter (e) cooling the ion-containing polymer sheet thereby obtaining an optically biaxial sheet.
Claim 3
Dependent Claim
14 words
The method according to claim 1, wherein the ion-containing polymer is an ionomer resin.
Claim 4
Dependent Claim
17 words
The method according to claim 2, wherein the ionomer resin has ethylene-methacrylate copolymer bridged with metal ions.
Claim 5
Dependent Claim
20 words
The method according to claim 2, wherein heating step (c) includes pressing the ionomer resin sheet between the two substrates.
Claim 6
Dependent Claim
16 words
The method according to claim 2, wherein heating step (c) is conducted in an autoclave furnace.
References Cited (Backward Citations)
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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) | 1997-03-28 | 1997-09-27 | 1998-03-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-03-28 | 2001-09-27 | 2002-03-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-03-28 | 2005-09-27 | 2006-03-29 | $7700.00 | Window Closed / Lapsed |