EP0367616A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Optical liquid crystal element
Assignee: Panasonic Holdings Corp
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Filing: 1989-11-02
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Granted: —
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Expires: 2009-11-02
Abstract
Abstract Disclosed is an electro-optic element, such as a liquid crystal, which exhibits optically rotatory dispersion and in which a pair of phase difference films (8, 9) having generally orthogonal stretching axes are disposed between a pair of polarizing plates (1, 2). The disposition of stretching axis directions (10, 11), arrangements (6, 7) of a liquid crystal cell (5) and transmission axis directions (3, 4) of the polarizing plates (1, 2) are optimized to achieve an increase in the angle of visibility, an increase in the contrast and improvements in color tones.
Inventors
- 👤 Hiroshi Watanabe
- 👤 Nobuyasu Yamagishi
- 👤 Kazuo Yokoyama
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-30 05:49
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; H; H04; H04N; H04N9/00; H04N9/12; H04N9/31; H04N9/3141; H04N9/315; H04N9/3167; G02F1/133; G02F1/1333; G02F1/1335; G02F1/13363; G02F1/137; G02F1/139; G02F1/1396; G02F1/1397; G02F2413/00; G02F2413/02; G02F2413/08
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
100 words
An electro-optic element comprising: a nematic liquid crystal cell having wtisted arrangements; a pair of polarizing plates respectively disposed on the obverse and reverse sides of said liquid crystal cell; and at least a pair of phase difference plates disposed between said pair of polarizing plates; wherein the stretching axes of said pair of phase difference films cross each other generally at right angles, and an arrangement direction of said nematic liquid crystal cell is generally parallel to the direction of the stretching axis of the corresponding one of said phase difference films adjacent to said nematic liquid crystal cell.
Claim 2
Dependent Claim
100 words
An electro-optic element comprising: a nematic liquid crystal cell having wtisted arrangements; a pair of polarizing plates respectively disposed on the obverse and reverse sides of said liquid crystal cell; and at least a pair of phase difference plates disposed between said pair of polarizing plates; wherein the stretching axes of said pair of phase difference films cross each other generally at right angles, and an arrangement direction of said nematic liquid crystal cell is generally parallel to the direction of the stretching axis of the corresponding one of said phase difference films adjacent to said nematic liquid crystal cell.
Claim 3
Dependent Claim
45 words
An electro-optic element according to claim 1, wherein the transmission axis of one of said polarizing plates and the stretching axis of the corresponding one of said phase difference films adjacent to said one of said polarizing plates cross each other generally at right angles.
Claim 4
Dependent Claim
27 words
An electro-optic element according to claim 2, wherein said pair of phase difference films are disposed between said liquid crystal cell and one of said polarizing plates.
Claim 5
Dependent Claim
71 words
An electro-optic element according to claim 1, wherein the angle at which the stretching axes of said pair of phase difference films cross each other is larger than 90°, while the angle at which the transmission axis of one of said polarizing plates and the stretching axis of the corresponding one of said phase difference films adjacent to said one of said polarizing plates cross each other is smaller than 90°.
Claim 6
Dependent Claim
31 words
An electro-optic element according to claim 1, wherein said phase difference films are equalized in the product of refractive index anisotropy An and the phase difference film thickness d, i.e., Δn·d.
Claim 7
Dependent Claim
27 words
An electro-optic element according to claim 1, one of said polarizing plates and one or both of said phase difference films constitute a composite film integrally formed.
Claim 8
Dependent Claim
21 words
An electro-optic element according to claim 6, wherein said composite film is used as a substrate of said liquid crystal cell.
Claim 9
Dependent Claim
21 words
An electro-optic element according to claim 1, wherein at least one optical isomer is provided between said pair of polarizing plates.
Claim 10
Dependent Claim
63 words
An electro-optic element according to claim 8, wherein said optical isomer includes a nematic liquid crystal which is twisted reversely relative to said liquid crystal cell with a twist angle equal to that of said liquid crystal cell, and in which the product of refractive index anisotropy Δn and the cell thickness d, Δn.d is equal to that of said liquid crystal cell.
References Cited (Backward Citations)
No citation records indexed.
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