Patent US4626071A successfully refreshed from Google Patents.
US4626071A
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Optical filter made of inorganic material for red light
Assignee: Okuno Chemical Industries Co Ltd
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Filing: 1985-06-17
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Granted: 1986-12-02
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Expires: 2005-06-17
Abstract
Abstract An optical filter made of inorganic material for red light which transfers red light and absorbs all of the other colored lights can be realized by sticking an inorganic mixture powder pasted by mixing with screen oil on a glass substrate and firing it. The mixture includes sulfates of copper, alkali metal and alkali earth metal. The contrast of the picture displayed on a display device can be increased significantly by reducing the reflection of incident ambient light without the reduction of brightness on account of the application of the above optical filter onto the displaying screen thereof.
Inventors
- 👤 Masatoshi Wada
- 👤 Shigekazu Matsubara
- 👤 Yukikazu Moritsu
- 👤 Tetsuo Sakai
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 17:51
CPC Classifications
C; C03; C03C; C03C17/00; C03C17/22; G; G02; G02B; G02B5/00; G02B5/20; G02B5/201; G02B5/22; G02B5/226; C03C2217/00; C03C2217/20; C03C2217/29; C03C2218/00; C03C2218/10; C03C2218/11; C03C2218/119; C03C2218/17
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
63 words
An optical filter made of inorganic material for red light, comprising a glass substrate, and a layer sticked on said glass substrate and fired, which is made of inorganic materials including indispensable constituents consisting of copper sulfate 1 to 70 parts by weight, alkali metal sulfate 20 to 90 parts by weight and alkali earth metal sulfate 10 to 80 parts by weight.
Claim 2
Dependent Claim
63 words
An optical filter made of inorganic material for red light, comprising a glass substrate, and a layer sticked on said glass substrate and fired, which is made of inorganic materials including indispensable constituents consisting of copper sulfate 1 to 70 parts by weight, alkali metal sulfate 20 to 90 parts by weight and alkali earth metal sulfate 10 to 80 parts by weight.
Claim 3
Dependent Claim
28 words
An optical filter made of inorganic material for red light as claimed in claim 1, wherein said inorganic materials are pulverized and pasted by mixing with screen oil.
Claim 4
Dependent Claim
31 words
An optical filter made of inorganic material for red light as claimed in claim 2, wherein said inorganic materials are added with inorganic filling material 5 to 50 parts by weight.
Claim 5
Dependent Claim
26 words
An optical filter made of inorganic material for red light as claimed in claim 3, wherein said inorganic materials are further added with an organic vehicle.
Claim 6
Dependent Claim
25 words
An optical filter made of inorganic material for red light as claimed in claim 1, wherein a superficial portion of said glass substrate is tinned.
Claim 7
Dependent Claim
54 words
An optical filter made of inorganic material for red light as claimed in claim 1, wherein said alkali metal sulfate is selected from a group including lithium sulfate, sodium sulfate and potassium sulfate and said alkali earth metal sulfate is selected from a group including zinc sulfate, calcium sulfate, magnesium sulfate and barium sulfate.
Claim 8
Dependent Claim
37 words
An optical filter made of inorganic material for red light as claimed in claim 3, wherein said inorganic filling material is selected from a group including alumina, titanium oxide, zirconia, zirconium silicate, calcium carbonate and iron oxide.
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) | 1989-12-01 | 1990-06-02 | 1990-12-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-12-01 | 1994-06-02 | 1994-12-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-12-01 | 1998-06-02 | 1998-12-02 | $7700.00 | Window Closed / Lapsed |