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:
Apr. 16, 2002
Filed:
Jun. 30, 1999
Shigekazu Yamagishi, Takatsuki, JP;
Yoshihiro Masumoto, Kobe, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
Randomly polarized light from a light source ( ) enters a polarization separation section ( ) through an integrator optical system ( ) including a second lens plate ( ) designed to have variant apertures. The polarization separation section ( ) separates the incident light into two polarized lights whose polarization directions are orthogonal to each other. Then, the polarization directions of these polarized lights are aligned by a polarization conversion section ( ). Thus, a polarized-light illumination unit in which polarization directions of randomly polarized light is converted into a desired polarization direction and at the same time the spread of illumination light can be suppressed can be obtained. Such a polarized-light illumination unit can be used suitably as an illumination unit for a projection-type image display unit using a liquid crystal light valve for modulating light by utilizing polarization and enables both the reduction in cost and the increase in luminance in the projection-type image display unit.