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EP0166370A2 Expired / Lapsed EP ⏱️ 0.0 years remaining

Optical filter made of inorganic material for red light

Assignee: Okuno Chemical Industries Co Ltd
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Filing: 1985-06-19
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Granted: —
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Expires: 2005-06-19
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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, which mixture includes sulfates of cooper, alkali metal and alkali earth metal. The contrast of picture displayed on a display device can be extremely increased 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 Okuno Chemical Ind. Co. Ltd. Wada
  • 👤 Shigekazu Okuno Chemical Ind. Co. Ltd. Matsubara
  • 👤 Yukikazu Okuno Chemical Ind. Co. Ltd. Moritsu
  • 👤 Tetsuo Sakai

Bibliographic Details

Application Number —
Jurisdiction EP
Data Source google_patents
Last Synchronized 2026-11-05 20:20
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 25 words
An optical filter made of inorganic material for red light as claimed in claim 3, wherein said inorganic materials are further added with 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.

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