Ferroelectric liquid crystal panel having a ferroelectric optical compensating liquid crystal cell

• US 5,126,864 A
• Filed: 02/16/1990
• Issued: 06/30/1992
• Est. Priority Date: 03/14/1989
• Status: Expired due to Fees

• Current Assignee: Stanley Electric Company Limited
• Original Assignee: Stanley Electric Company Limited
• Inventors: Ide, Masafumi, Akiyama, Ryouichi, Yoneda, Koutaro, Ui, Kazuhisa
• Primary Examiner(s): Zazworsky, John
• Assistant Examiner(s): Duong, Tai V.
• Application Number:
  US07/481,139
• Time in Patent Office: 865 Days
• Field of Search: 350/335, 350/350 S, 350/347 E, 350/347 R, 350/337, 350/332, 350/333, 340/784
• US Class Current: 349/75
• CPC Class Codes: G02F 1/13471 in which all the liquid crystal cells or layers remain transparent, e.g. FLC, ECB, DAP, HAN, TN, STN, SBE-LC cells G02F1/13475 takes precedence
• CPC Class Codes: G02F 1/141 using ferroelectric liquid crystals
• CPC Class Codes: G02F 2203/30 Gray scale
• CPC Class Codes: G09G 2300/023 Display panel composed of stacked panels
• CPC Class Codes: G09G 3/36 using liquid crystals

Abstract

A ferroelectric liquid crystal panel comprising 2 layers of liquid crystal cells, each of which comprises a ferroelectric crystal sealed between two substrates and then is laminated together; wherein one of said liquid crystal cells is operated as a panel driving liquid crystal cell and the other of said liquid crystal cells is operated as an optical compensating cell, while both said liquid crystal cells being driven by rectangular wave AC signals. Furthermore, the ferroelectric liquid crystal panel is constructed to operate in an intermediate tone by varying the phases of said rectangular wave AC signals applied to the liquid crystal cells of the first and second layers.

Claims

1. A ferroelectric liquid crystal panel comprising 2 layers of liquid crystal cells disposed between two polarizers, each of said cells comprising a ferroelectric liquid crystal sealed between two substrates, wherein said cells are laminated together and, wherein one of said liquid crystal cells is operated as a panel driving liquid crystal cell and the other of said liquid crystal cells is operated as an optical compensating cell, both said liquid crystal cells being driven individually by rectangular wave AC signals and wherein said ferroelectric liquid crystal panel is operated in an intermediate tone by varying the phases of said rectangular wave AC signals applied to the liquid crystal cells of the first and second layers.