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US 4,824,210 AGranted
Liquid crystal projector
AssigneeCasio Computer Co., Ltd.
InventorTatsuo Shimazaki
Life of this patent
Estimating the term…
Abstract
A liquid crystal projector is disclosed, which comprises a light source, a TV type liquid crystal display panel and a projecting lens system. The liquid crystal display panel faces the screen and is inclined with respect to a line perpendicular to an optical axis connecting the center of the liquid crystal display panel and the center of a screen by the suitable visual field angle of the liquid crystal display panel.
Claims3
A liquid crystal projector comprising:
- a case provided with a projecting window;
- a light source disposed within said case, said light source including a lamp and a reflecting mirror having an optical axis;
- means for converting light emitted from said light source into a parallel light;
- a liquid crystal display panel for displaying an image, said liquid crystal display panel being tilted at a predetermined angle with respect to said optical axis of said reflecting mirror and having a back surface irradiated with said parallel light;
- condenser lens means for condensing light passing through said liquid crystal display panel;
- projecting lens means for projecting in a magnified fashion the image displayed on said liquid crystal display panel by the light condensed by said condenser lens means through said projecting window of said case;
- screen means arranged to receive the magnified image projected from said projecting lens means thereon for displaying said magnified image, said screen means being tilted at a predetermined angle in a direction opposite to the tilting direction of said liquid crystal display panel;
- and
- means for cooling said liquid crystal display panel;
- an angle .theta. formed between said liquid crystal display panel and a line perpendicular to said optical axis of said reflecting mirror bearing the following relationship with an angle .theta.' formed between said liquid crystal display panel and a vertical line of said screen means:
- (Zo+y tan .theta.)(Zo'+y' tan .theta.')=f.multidot.f'=-f.sup.2
- where:
- f:
- focal length of said projecting lens means on the side of said liquid crystal display panel;
- Zo:
- position on said optical axis of said reflecting mirror with "f" set as the origin;
- y:
- position on a line perpendicular to said optical axis;
- f':
- focal length of said projecting lens means on the side of said screen means;
- Zo':
- position on said optical axis of said reflecting mirror with "f'" set as the origin;
- and
- y':
- position on a line perpendicular to said optical axis.
22 more elements
A liquid crystal projector comprising:
- a light source including a lamp and a reflecting mirror having an optical axis;
- a liquid crystal display panel for displaying an image, said liquid crystal display panel being tilted at a predetermined angle with respect to said optical axis of said reflecting mirror and being illuminated on a backside thereof with light from said light source;
- projecting lens means for projecting in a magnified fashion the image displayed on said liquid crystal panel;
- and
- screen means arranged to receive the magnified image projected from said projecting lens thereon for displaying said magnified image, said screen means being tilted at a predetermined angle in a direction opposite to the tilting direction of said liquid crystal display panel;
- an angle .theta. formed between said liquid crystal display panel and a line perpendicular to said optical axis of said reflecting mirror bearing the following relationship with an angle .theta.' formed between said liquid crystal display panel and a vertical line of said screen means:
- (Zo+y tan .theta.)(Zo'+y' tan .theta.')=f.multidot.f'=-f.sup.2
- where:
- f:
- focal length of said projecting lens means on the side of said liquid crystal display panel;
- Zo:
- position on said optical axis of said reflecting mirror with "f" set as the origin;
- y:
- position on a line perpendicular to said optical axis;
- f':
- focal length of said projecting lens means on the side of said screen means;
- Zo':
- position on said optical axis of said reflecting mirror with "f'" set as the origin;
- and
- y':
- position on a line perpendicular to said optical axis.
18 more elements
Dependencies are inferred from the claim text.