The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 27, 2009
Filed:
Sep. 29, 2006
Yasuhiro Daiku, Iruma, JP;
Yasuhiro Daiku, Iruma, JP;
Casio Computer Co., Ltd., Tokyo, JP;
Abstract
The invention has light source unit disposed at opposite side to observer side of liquid crystal display device for selectively emitting linearly-polarized light and non-polarized light, and retardation element disposed between liquid crystal display device and light source unit. Plurality of first and second layers whose slow axes are arranged in different directions are alternately arranged on a surface of retardation element that faces light source unit, and plurality of third and fourth layers whose slow axes are arranged in different directions are arranged on the other surface, such that third layers face first layers and fourth layers face second layers. First to fourth layers are arranged such that polarization plane of light passing through first and third layers and second and fourth layers is rotated by 90°, and polarization plane of light passing through first and fourth layers and second and third layers is rotated by 180° or 0°.