Title:
LIQUID CRYSTAL DISPLAY DEVICE
Document Type and Number:
Japanese Patent JPH0580293
Kind Code:
A
Abstract:
PURPOSE:To provide a proper black-and-white display by making at least the retardation of a lower phase plate on a low-wavelength side smaller than the retardation value of an upper phase plate. CONSTITUTION:The black-and-white display type liquid crystal display device is constituted by providing an STN type liquid crystal display element 1 with the lower phase plate 6 and upper phase plate 7; and the relation between wavelength and the retardation value DELTAnd of the lower phase plate 6 and the relation between the wavelength and the retardation value DELTAnd of the upper phase plate 7 are so determined that the retardation value of the lower phase plate 6 is smaller than the retardation value of the upper phase plate 7 irrespectively of the wavelength or at least on the low wavelength side. Consequently, the STN type liquid crystal display element 1 can correct elliptically polarized light into nearly linearly polarized light, so the proper black-and-white display is provided and this device is effective.
Inventors:
NAKAMURA YOSHIAKI
Application Number:
JP16422891A
Publication Date:
April 02, 1993
Filing Date:
July 04, 1991
Export Citation:
Assignee:
HITACHI LTD
HITACHI DEVICE ENG
HITACHI DEVICE ENG
International Classes:
G02F1/133; G02F1/1335; (IPC1-7): G02F1/133; G02F1/1335
Attorney, Agent or Firm:
Junnosuke Nakamura (1 outside)
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