US4822146A
Expired / Lapsed
US
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Optical modulation element
Assignee: Canon Inc
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Filing: 1987-04-02
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Granted: 1989-04-18
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Expires: 2007-04-02
Abstract
Abstract An optical modulation element which enables substantially total transmission of incident light and provides a high contrast when it as used as a display element, thereby enabling multiplex driving.
Inventors
- 👤 Masato Yamanobe
- 👤 Yasuyuki Watanabe
- 👤 Yukitoshi Ohkubo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 09:23
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/133; G02F1/1333; G02F1/1335; G02F1/137; G02F1/139; G02F1/29; G02F1/292; G02F2201/00; G02F2201/30; G02F2201/305
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
113 words
An optical modulation device comprising: a first substrate; a second substrate disposed opposingly to said first substrate; a liquid crystal layer and optical member alternately arranged between said first and second substrates and substantially in a plane extending parallel to the planes defined by said both substrates, said liquid crystal layer including liquid crystal molecules whose refractive index changes between maximum refractive index Nmax and minimum refractive index Nmin in accordance with their orientation an said optical member having refractive index Ng about equal to refractive index N.sub.θ where Nmax>N.sub.θ >Nmin; and control means for controlling the orientation of said liquid crystal molecules to change the refractive index of said liquid crystal layer.
Claim 2
Dependent Claim
113 words
An optical modulation device comprising: a first substrate; a second substrate disposed opposingly to said first substrate; a liquid crystal layer and optical member alternately arranged between said first and second substrates and substantially in a plane extending parallel to the planes defined by said both substrates, said liquid crystal layer including liquid crystal molecules whose refractive index changes between maximum refractive index Nmax and minimum refractive index Nmin in accordance with their orientation an said optical member having refractive index Ng about equal to refractive index N.sub.θ where Nmax>N.sub.θ >Nmin; and control means for controlling the orientation of said liquid crystal molecules to change the refractive index of said liquid crystal layer.
Claim 3
Dependent Claim
50 words
An optical modulation device according to claim 1, wherein materials of said liquid crystal layer and said optical member are selected such that such refractive indices N.sub.θ and N g become about equal to each other with respect to all wavelengths in a range of 400 nm through 700 nm.
Claim 4
Dependent Claim
42 words
An optical modulation device according to claim 2, wherein said refractive index Nmax is equal to extraordinary refractive index Ne of said liquid crystal molecules and said refractive index Nmin is equal to ordinary refractive index No of said liquid crystal molecules.
Claim 5
Dependent Claim
22 words
An optical modulation device according to claim 3, wherein said liquid crystal molecules are nematic liquid crystal having a positive dielectric anisotropy.
Claim 6
Dependent Claim
42 words
An optical modulation device according to claim 1, wherein said liquid crystal layer is constructed such that a difference between said maximum and minimum refractive indices is about constant with respect to all wavelengths in range of 400 nm through 700 nm.
Claim 7
Dependent Claim
87 words
In an optical modulation device comprising first and second substrates, a relief structure of a predetermined period formed between the first and second substrates, liquid crystal sealed in groove portions of the relief structure and means for changing the refractive index of the liquid crystal to modulate an incident light, the improvement being that the refractive index Ng of said relief structure is about equal to refractive index N.sub.θ where the maximum refractive index Nmax of said liquid crystal>N.sub.θ >minimum refractive index Nmin of said liquid crystal.
Claim 8
Dependent Claim
87 words
In an optical modulation device comprising first and second substrates, a relief structure of a predetermined period formed between the first and second substrates, liquid crystal sealed in groove portions of the relief structure and means for changing the refractive index of the liquid crystal to modulate an incident light, the improvement being that the refractive index Ng of said relief structure is about equal to refractive index N.sub.θ where the maximum refractive index Nmax of said liquid crystal>N.sub.θ >minimum refractive index Nmin of said liquid crystal.
Claim 9
Dependent Claim
46 words
An optical modulation device according to claim 6, wherein material of said liquid crystal and relief structure are such that the refractive indices N.sub.θ and Ng are about equal to each other with respect to all wavelengths in a range of 400 nm through 700 nm.
References Cited (Backward Citations)
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