Method of making liquid crystal device having plural stripe-shaped ribs on one substrate

• US 5,499,130 A
• Filed: 06/05/1995
• Issued: 03/12/1996
• Est. Priority Date: 02/20/1991
• Status: Expired due to Fees

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Okada, Shinjiro
• Primary Examiner(s): Sikes, William L.
• Assistant Examiner(s): MAI, HUY KIM
• Application Number:
  US08/465,567
• Time in Patent Office: 281 Days
• Field of Search: 359/54, 359/76, 359/87, 359/99, 359/100
• US Class Current: 349/139
• CPC Class Codes: G02F 1/133784 by rubbing
• CPC Class Codes: G02F 1/134309 characterised by their geometrical arrangement
• CPC Class Codes: G02F 1/141 using ferroelectric liquid crystals
• CPC Class Codes: G02F 2203/30 Gray scale

Abstract

There is disclosed a ferroelectric liquid crystal device such as a chiral smectic liquid crystal device which is suitable for a gradation display. A chiral smectic liquid crystal is sandwiched between electrode substrates and is driven by an electric field which is applied through electrodes formed on the electrode substrates. At least one of the opposite electrode substrate surfaces periodically has a shape like a stripe-shaped rib. Liquid crystal molecules are oriented so that the normal lines of a plurality of layers which are constructed by a plurality of molecules and are arranged in a uniform direction when they are projected onto the electrode substrate surfaces perpendicularly cross the longitudinal direction of the stripe-shaped rib.

Claims

1. A method for producing a liquid crystal element, comprising the steps of:

selecting a pair of electrode substrates;

forming a configuration of periodic stripe-like ribs on at least one of the pair of electrode substrates;

subjecting each of said pair of electrode substrates to a rubbing processing in which the rubbing of the lower substrate is made in a direction at an angle rotating in a clockwise direction from a rubbing direction of the upper substrate;

selecting a chiral smectic liquid crystal which changes state between isotropic phase, cholesteric phase and smectic A phase according to temperature;

injecting said chiral smectic liquid crystal between said pair of electrode substrates;

providing means for applying a voltage between said pair of electrode substrates, said voltage forming a transmittance in said liquid crystal according to a gradation ;

wherein a normal line with respect to plural layers arranged in a uniform direction composed of plural molecules projected onto the surface of said electrode with said stripe-like ribs crosses said stripe-like ribs.

2. A method according to claim 1, wherein a width of said rib is 10 μ

m-500 μ

m.

3. A method for producing a liquid crystal element, comprising the steps of:

selecting a pair of electrode substrates;

forming a configuration of periodic stripe-like ribs on at least one of the pair of electrode substrates;

subjecting an electrode substrate to a rubbing processing in a direction;

selecting a chiral smectic liquid crystal which changes state between isotropic phase, cholesteric phase and smectic A phase according to temperature;

injecting said chiral smectic liquid crystal between said pair of electrode substrates;

providing means for applying a voltage between said pair of electrode substrates, said voltage forming a transmittance in said liquid crystal according to a gradation;

wherein a normal line with respect to plural layers arranged in a uniform direction composed of plural molecules projected onto the surface of said electrode with said stripe-like ribs crosses said stripe-like ribs.