Patent EP0205187A2 successfully refreshed from Google Patents.
EP0205187A2
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EP
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Optical disc memory with liquid crystal
Assignee: Semiconductor Energy Laboratory Co Ltd
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Filing: 1986-06-13
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Granted: —
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Expires: 2006-06-13
Abstract
Abstract An improved magneto-optical disc memory with a ferroelectric liquid crystal (FLC) isshown. As FLC a chiral smectic liquid crystal is employed to exhibit a bistability between a pair of substrates which have easy polarization axes normal to each other. Informations to be recorded are written on the disc in terms of a binary system by use of the bistability.
Inventors
- 👤 Yamazaki Shunpei
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-30 20:18
CPC Classifications
G; G11; G11B; G11B13/00; G11B7/00; G11B7/004; G11B7/0055; G11B7/00555; G11B7/24
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
43 words
An optical nonvolatile disc memory comprising: a plurality of laminated molecular layers of liquid crystal, the molecules of the liquid crystal being rotatable with a fixed tilt angle with reference to the layer normal; and means for keeping the attitude of each molecule.
Claim 2
Dependent Claim
43 words
An optical nonvolatile disc memory comprising: a plurality of laminated molecular layers of liquid crystal, the molecules of the liquid crystal being rotatable with a fixed tilt angle with reference to the layer normal; and means for keeping the attitude of each molecule.
Claim 3
Dependent Claim
65 words
An information reading system comprising: a disc memory of claim 1 on which is stored information to be read; means for irradiating the disc memory with light; means for receiving the light having passed through the molecular layers and then through a polarizing means; and means for reproducing the information recorded on the disc memory on the basis of the intensity of the passed light.
Claim 4
Dependent Claim
44 words
An disc memory of claim 1, further comprising: opposed substrates between which the plurality of molecular layers are disposed perpendicularly to the substrates, and the inner surfaces of the substrates opposite to each other and contiguous to the layers, functioning as the keeping means.
Claim 5
Dependent Claim
31 words
A disc memory of claim 3, wherein at least one of said substrate formed with an inner oriented surface according to which the molecules are aligned into the plurality of layers.
Claim 6
Dependent Claim
58 words
An information reading system comprising: a disc memory of claim 1 on which are stored information to be read; means for irradiating the disc memory with polarized light; means for receiving the light having passed through the moleculars; means for reproducing the information recorded on the disc memory on the basis of the intensity of the passed light.
Claim 7
Dependent Claim
15 words
A system of claim 5, wherein said liquid crystal is a ferroelectric chiral smectic C.
Claim 8
Dependent Claim
34 words
A system of claim 5 wherein an agent is added to the quantity of the liquid crystal constituting said layers in the disc to enhance the apparent absorption anisotropy of the plurality of layers.
Claim 9
Dependent Claim
11 words
A system of claim 7 wherein said agent is dichromatic substance.
Claim 10
Dependent Claim
66 words
A system of claim 6 further comprising: means for applying to the disc memory a strong electric field sufficient to arrange the molecules in the same attitude in spite of presence of the keeping means; and means for applying to the disc memory a weak electric field against which the molecules can substantially hold their attitude, the irradiating process being made under such weak electric field.
References Cited (Backward Citations)
No citation records indexed.
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