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:
Jul. 24, 1990
Filed:
Feb. 23, 1989
Yoshito Miyatake, Neyagawa, JP;
Yoshihiro Masumoto, Neyagawa, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
A projection display apparatus has a light source, a component color separator, a light transmitter(s), three light valves, a light combiner, a single projection lens, and a drive circuit. The light transmitter includes an input side convergent lens for producing a real image of a luminous element in the light source at a location adjacent to a central convergent lens. The central convergent lens produces a real image of an object situated about a position of the input side convergent lens at a location adjacent to an output side convergent lens. The output side convergent lens permits its output light to reach the projection lens. Accordingly, divergent light is converged along a considerably extending portion of the optical path and directed to the projection lens so that the efficiency of light in use can be improved, thus allowing the projection display apparatus to remain compact in size and provide a great light output power.