Liquid crystal display apparatus

• US 7,486,351 B2
• Filed: 05/25/2005
• Issued: 02/03/2009
• Est. Priority Date: 05/25/2004
• Status: Expired due to Fees

• Current Assignee: Panasonic Liquid Crystal Display Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Hitachi Displays Limited (Japan Display Incorporated)
• Inventors: Tanno, Junji, Morimoto, Masateru, Ochiai, Takahiro, Itou, Osamu, Imayama, Hirotaka
• Primary Examiner(s): Duong; Thoi V
• Application Number:
  US11/138,869
• Publication Number:
  US 20050264720A1
• Time in Patent Office: 1,350 Days
• Field of Search: 349/99, 349/123, 349/114, 349/141, 349/96, 349/129, 349/143, 349/117
• US Class Current: 349/99
• CPC Class Codes: G02F 1/133528 Polarisers
• CPC Class Codes: G02F 1/133555 Transflectors
• CPC Class Codes: G02F 1/133707 Structures for producing distorted electric fields, e.g. bumps, protrusions, recesses, slits in pixel electrodes
• CPC Class Codes: G02F 1/133757 with different alignment orientations
• CPC Class Codes: G02F 1/134363 for applying an electric field parallel to the substrate, i.e. in-plane switching [IPS]

Abstract

A liquid crystal display apparatus includes a transmissive display portion having the same liquid crystal alignment directions and transmissive axes of the polarizers as the transmissive IPS liquid crystal display apparatus. Further, the liquid crystal layer of its reflective display portion has a retardation of a quarter wave. The liquid crystal alignment directions of the reflective display portion are set to be crossed with the transmissive axes of the polarizers in the transmissive display portion at an angle of 45 degrees.

Claims

1. A liquid crystal display apparatus comprising:

a first substrate;

a second substrate;

a liquid crystal layer laid between said first and second substrates;

said second substrate having a pixel electrode and a common electrode so that an electric field may be applied between said pixel electrode and said common electrode in substantially parallel to said substrate surface, for driving said liquid crystal layer;

one pixel having a reflective display portion and a transmissive display portion;

a first polarizer and a second polarizer located outsides of said first and second substrates;

an alignment layer imparting to the liquid crystal layer a first liquid crystal alignment direction in said transmissive display portion and a second liquid crystal alignment direction in said reflective display portion; and

said first and second polarizers having their transmissive axes crossed at right angles with each other, and wherein the first liquid crystal alignment direction in said transmissive display portion is in parallel to any one of said transmissive axes of said first and second polarizers and the second liquid crystal alignment direction in said reflective display portion is crossed with said transmissive axes of said first and second polarizers at an angle of 40 to 50 degrees.

2. A liquid crystal display apparatus as claimed in claim 1, wherein a retardation of said liquid crystal layer in said reflective display portion is a quarter wave.

3. A liquid crystal display apparatus comprising:

a first substrate;

a second substrate;

a liquid crystal layer laid between said first and second substrates;

said second substrate having a pixel electrode and a common electrode so that an electric field may be applied between said pixel electrode and said common electrode in substantially parallel to said substrate surface, for driving said liquid crystal layer;

one pixel having a reflective display portion and a transmissive display portion;

a first polarizer and a second polarizer located outsides of said first and second substrates;

an alignment layer imparting to the liquid crystal aver a first liquid crystal alignment direction in said transmissive display portion and a second liquid crystal alignment direction in said reflective display portion; and

said first and second polarizers having their transmissive axes crossed with each other at right angles, and wherein the first liquid crystal alignment direction in the transmissive display portion is located in parallel to any one of transmissive axes of said first and second polarizers and the second liquid crystal alignment direction in the reflective display portion is crossed with the transmissive axes of said first and second polarizers at an angle of 40 to 50 degrees at least on the boundary closer to a light incident plane.