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:
Mar. 15, 1994
Filed:
Mar. 04, 1992
Nobuhiro Konuma, Yokohama, JP;
Hiroshi Jitsukata, Yokohama, JP;
Tetsu Ohishi, Hiratsuka, JP;
Kyohei Fukuda, Fujisawa, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
In a polarization transforming optics having a polarizing beam splitter (PBS) for transforming x-direction incident light flux from a metal halide light source into a single linearly (z direction) polarized light flux beam heading in the y direction and delivering the beam to, preferably, a light valve of a liquid crystal display (LCD) in a coordinate space, the PBS splits the incident light flux from the light source into split light flux beams, separates the split light flux beams into linearly polarized light flux beams having polarizing directions which are orthogonal to each other, and delivers two linearly polarized outgoing light flux beams having polarizing directions which are orthogonal to each other and heading in directions parallel to a polarizing direction plane. One of the two outgoing light flux beams is deflected by a single mirror to have the same heading direction and polarizing direction as those of the other. The PBS is constructed by jointing together, for example, a quadrangular pyramidal prism and two triangular pyramidal prisms. A PBS film is formed at each joint interface and a surface in contact with air of each prism acts as a total reflection mirror surface. No wave plate is used to provide a compact apparatus having a high light utilization efficiency.