Title:
LIQUID CRYSTAL MAGNIFICATION PROJECTION
Document Type and Number:
Japanese Patent JPS6458191
Kind Code:
A
Abstract:
PURPOSE:To obtain a bright projecting picture by providing a polarizer in front of the dichroic mirror applying color decomposition of light in a magnification projector projecting a picture through magnification on a screen by means of a projecting lens after the synthesis by the dichroic prism and cooling only the polarizer efficiently. CONSTITUTION:An elliptic collective reflection mirror 2 is provided to improve the light collecting efficiency in the back direction of the light source 1. A reflecting mirror 3 transmitting an infrared-ray and reflecting a visual light in the collected light and the polarizer 4 are provided sequentially. A color element system polarizing plate with heat resistance withstanding the temperature rise incurred by absorbing the visual light is used for the polarizer 4. The light from the light source 1 is collected by the collection reflecting mirror 2, the visual light is reflected by the reflecting mirror 3, the remaining infrared ray is transmitted and a thermal ray is eliminated. The reflected visual light transmits through the polarizer 4. In this case, since the polarizer 4 is cooled by a cool wind, even if nearly a half the visual light to be transmitted is absorbed, the temperature rise is prevented.
Inventors:
KANEMOTO AKIHIKO
Application Number:
JP21468387A
Publication Date:
March 06, 1989
Filing Date:
August 28, 1987
Export Citation:
Assignee:
RICOH KK
International Classes:
H04N9/31; G02F1/13; (IPC1-7): G02F1/13; H04N9/31
Attorney, Agent or Firm:
Akira Kashiwagi
Previous Patent: 市販の薄型のテレビジョンを装着可能としたテレビジョン装着家具、当該...
Next Patent: NOISE REDUCTION CIRCUIT FOR VIDEO SIGNAL
Next Patent: NOISE REDUCTION CIRCUIT FOR VIDEO SIGNAL