Patent US4001583A successfully refreshed from Google Patents.
EP0791848A2
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EP
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Display and method of operating a display
Assignee: Sharp Corp
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Filing: 1997-02-19
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Granted: —
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Expires: 2017-02-19
Abstract
Abstract A liquid crystal display comprises a matrix of pixels 7, for instance formed at the intersections of data electrodes 1 and split strobe electrodes 2 and 3. Each pixel 7 is divided into first and second sub-pixels 8 and 9. The first sub-pixels 8 have parallel input and output polarisers 31, 34 whereas the second sub-pixels 9 have perpendicular input and output polarisers 31, 35. In order to address an intermediate grey level, the sub-pixels 8 and 9 are switched to the grey level. Variations in the grey levels of the sub-pixels 8 and 9, for instance caused by temperature variations, act in opposite directions so that the average grey level of the whole pixel 7 varies relatively little.
Inventors
- 👤 Paul Bonnett
- 👤 Michael John Towler
- 👤 Akira Tagawa
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-24 12:07
CPC Classifications
G; G09; G09G; G09G3/00; G09G3/20; G09G3/34; G09G3/36; G09G3/3611; G09G3/3622; G09G3/3629; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/133; G02F1/1333; G02F1/1335; G02F1/133528; G02F1/133531; G02F1/1343; G02F1/134309; G02F1/134345; G09G2310/00; G09G2310/06; G09G2310/061; G09G2320/00; G09G2320/04; G09G2320/041; G09G3/2007
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
112 words
A liquid crystal display comprising a plurality of pixels (7), each of which is spatially divided to form a first sub-pixel (8) and a second sub-pixel (9), and a control arrangement (4, 5) for selectively switching each pixel (7) to an intermediate optical state between a maximum attenuation optical state and a minimum attenuation optical state by switching the first and second sub-pixels (8, 9) to the intermediate optical state, characterised in that each of the first sub-pixels (8) has input and output linear polarisers (31, 34) whose polarisation directions are parallel and each of the second sub-pixels (9) has input and output linear polarisers (31, 35) whose polarising directions are orthogonal.
Claim 2
Dependent Claim
31 words
A display as claimed in Claim 1, characterised by a spatially uniformly polarising layer (31) forming one of the input and output polarisers of the first and second sub-pixels (8, 9).
Claim 3
Dependent Claim
47 words
A display as claimed in Claim 2, characterised by spatially non-uniformly polarising layer (32) having alternating elongate first and second regions (34, 35) forming the other of the input and output polarisers, the first and second regions (34, 35) being aligned with the first and sub-pixels, respectively.
Claim 4
Dependent Claim
35 words
A display as claimed in Claim 3, characterised in that the first and second regions (34, 35) of each adjacent pair are aligned with first and second sub-electrodes (2, 3) of a respective addressing electrode.
Claim 5
Dependent Claim
34 words
A display as claimed in any one of the preceding claims, characterised in that each of the pixels (7) comprises first and second display regions forming the first and second sub-pixels (8, 9), respectively.
Claim 6
Dependent Claim
24 words
A display as claimed in any one of the preceding claims, characterised in that the first and second sub-pixels (8, 9) are independently addressable.
Claim 7
Dependent Claim
31 words
A display as claimed in Claim 6, Characterised in that the control arrangement (4, 5) is arranged to refresh the first and second sub-pixels (8, 9) of each pixel (7) simultaneously.
Claim 8
Dependent Claim
31 words
A display as claimed in Claim 6, characterised in that the control arrangement (4, 5) is arranged to refresh the first and second sub-pixels (8, 9) of each pixel (7) sequentially.
Claim 9
Dependent Claim
25 words
A display as claimed in any one of the preceding claims, characterised in that the pixels (7) contain twisted nematic or supertwisted nematic liquid crystal.
References Cited (Backward Citations)
No citation records indexed.
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