Wire grid polarized and liquid crystal display device using the same

• US 8,199,282 B2
• Filed: 07/06/2011
• Issued: 06/12/2012
• Est. Priority Date: 10/20/2006
• Status: Active Grant

• Current Assignee: Panasonic Intellectual Property Corporation of America (Panasonic Holdings Corporation)
• Original Assignee: Hitachi Displays Limited (Japan Display Incorporated), Panasonic Liquid Crystal Display Company Limited (Panasonic Holdings Corporation)
• Inventors: Sugita, Tatsuya, Hirota, Shoichi
• Primary Examiner(s): DUONG, THOI V
• Application Number:
  US13/177,023
• Publication Number:
  US 20110261455A1
• Time in Patent Office: 342 Days
• Field of Search: 349/96, 349/9, 349/138, 349/113, 349/114, 359/485.05
• US Class Current: 349/96
• CPC Class Codes: G02B 5/3058 comprising electrically conductive elements, e.g. wire grids, conductive particles
• CPC Class Codes: G02F 1/133536 Reflective polarizers G02F1/13362 takes precedence
• CPC Class Codes: G02F 1/133548 Wire-grid polarisers
• CPC Class Codes: G02F 1/133565 inside the LC elements, i.e. between the cell substrates

Abstract

A wire grid polarizer includes fine metal wires arranged parallel to one another and thus transmitting TM-polarized light. A light absorbing layer for absorbing TE-polarized light is provided on at least one of the surfaces of the wire grid polarizer.

Claims

1. A wire grid polarizer comprising fine metal wires arranged parallel to one another and thus transmitting TM-polarized light,

wherein a light absorbing layer for absorbing TE-polarized light is provided on at least one of the surfaces of the wire grid polarizer and consists of composite fine lines, each fine line being a lamination of a plurality of composite layers, each composite layer consisting of a pair of a dielectric wire layer and a metal wire layer, and the composite layer being repeatedly stacked on each fine metal wire of the wire grid polarizer so that the dielectric wire layer and the metal wire layer are alternately stacked,

wherein a refractivity of a dielectric material of the dielectric wire layer is not less than 1.8 for the visible spectrum of light, and

wherein a metal of the metal wire layer of the lamination has a real part of complex refractive index of not less than unity and an extinction coefficient of not less than unity.

2. A wire grid polarizer as claimed in claim 1, wherein a light reflection layer is provided on the opposite side of the wire grid polarizer to the surface on which the light absorbing layer is disposed, the reflection layer reflecting TM-polarized light transmitted through the wire grid polarizer.

3. A wire grid polarizer as claimed in claim 1, wherein a refractive index of a material filled in spaces between the fine metal wires provided with the lamination of the plurality of composite layers is not more than 1.5.

4. A wire grid polarizer as claimed in claim 1, wherein at least one of the dielectric wire layer and the metal wire layer of each composite layer is a light absorber.

5. A wire grid polarizer as claimed in claim 1, wherein both of the dielectric wire layer and the metal wire layer of the composite layer are light absorbers.