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:
May. 21, 1996
Filed:
Jun. 07, 1995
Yoshihiro Watanabe, Yokohama, JP;
Hiroki Nakamura, Chigasaki, JP;
Nozomu Harada, Yokohama, JP;
Seiji Murakami, Fukaya, JP;
Tsutomu Sakamoto, Faukaya, JP;
Kazuki Taira, Kawasaki, JP;
Yutaka Saitoh, Fukaya, JP;
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Abstract
A display apparatus includes a light source, a modulating device for modulating light emitted from the light source, a modulating device driving unit for driving the modulating device, a first aperture stop unit arranged between the light source and the modulating device to limit a bundle of rays to be incident on the modulating device from the light source, the first aperture stop unit having an aperture with a variable size, a display screen onto which exit light from the modulating device is projected, a projection optical system for projecting the exit light from the modulating device onto the display screen, a second aperture stop unit arranged between the modulating device and the projection optical system to limit a bundle of rays to be incident on the projection optical system from the modulating device, the second aperture stop unit having an aperture with a variable size, a photosensor for detecting the display luminance on the display screen, and an aperture control unit for controlling the size of the aperture of at least one of the first and second aperture stop units on the basis of a display luminance signal from the photosensor.