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:
Aug. 10, 1999
Filed:
Jan. 02, 1997
Akira Daijogo, Tokyo, JP;
Shinsuke Shikama, Tokyo, JP;
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
A projection type display apparatus including a heater for heating the liquid crystal light valve. The heater includes a transparent electrically conductive film formed on a transparent substrate and is supplied with electric power therethrough to generate heat. The supplied electric power is controlled in accordance with the temperature of the liquid crystal light valve so that the liquid crystal layer in the liquid crystal light valve is in its optimum operating temperature range. The heater may include a filter through which the illumination luminous flux is incident upon the liquid crystal light valve. The filter passes only visible light when inclined within a certain range of angle with the luminous flux, and passes a progressively large amount of heat rays with increasing deviation of the angle from the certain range. A cold mirror and reflecting mirror may be used in place of the filter. The cold mirror reflects visible light of the illumination luminous flux to the liquid crystal light valve and passes heat rays to the reflecting mirror. The reflecting mirror is at an angle with the heat rays and reflects the heat rays to the liquid crystal light valve. The amount of the heat rays reflected to the liquid crystal light valve may be adjusted by varying the angle at which the heat rays is incident on the reflecting mirror.