Liquid crystal projector

• US 5,048,949 A
• Filed: 08/06/1990
• Issued: 09/17/1991
• Est. Priority Date: 11/26/1987
• Status: Expired due to Term

• Current Assignee: Casio Computer Company Limited
• Original Assignee: Casio Computer Company Limited
• Inventors: Sato, Makoto, Shimazaki, Tatsuo
• Primary Examiner(s): Cuchlinski, Jr., William A.
• Assistant Examiner(s): Dowling, William C.
• Application Number:
  US07/563,936
• Time in Patent Office: 407 Days
• Field of Search: 353/77, 353/78, 353/122, 353/30-31, 353/38, 353/20, 350/330, 350/331 R, 350/337, 350/128, 358/60-61, 358/231-232
• US Class Current: 353/77
• CPC Class Codes: G03B 21/10 Projectors with built-in or built-on screen
• CPC Class Codes: H04N 5/7441 the modulator being an array of liquid crystal cells
• CPC Class Codes: H04N 9/3141 Constructional details thereof details not peculiar to the presence of an electronic spatial light modulator G03B21/14

Abstract

A liquid crystal projector includes a liquid crystal panel, a light source for illuminating the liquid crystal panel, a back-projection type screen having on its surface a lenticular lens in which many vertical or horizontal stripe lenses are arranged in parallel, a projection lens for enlargedly projecting light transmitted through the liquid crystal panel onto the back-projection type screen, a light-falling polarized plate arranged between the light-falling plane of the liquid crystal panel and the light source, for transmitting the light from the light source, and oscillating in a predetermined direction, to fall on the liquid crystal panel, and an image-forming polarizing plate arranged between the light-outgoing plane of the liquid crystal panel and the projection lens or in a projection path from the projection lens to the screen, to allow the liquid transmitted through the liquid crystal panel, and oscillating in a predetermined direction, to pass through, thereby forming a light image.

Claims

1. A liquid crystal projector comprising:

a liquid crystal display panel;

a light source for illuminating said display panel;

a translucent back-projection type screen on a surface of which is formed a lenticular lens comprising a large number of stripe lenses arranged substantially in parallel;

projection means for projecting light supplied from said display panel onto said screen;

oscillating direction control means for causing the light transmitted through said display panel to be incident upon said screen in a direction of oscillation substantially perpendicular to the direction of length of said stripe lenses;

at least one mirror arranged between said projection means and said screen; and

means for causing S polarized light to be incident upon said at least one mirror.

2. A liquid crystal projector comprising:

a liquid crystal display panel;

a light source for illuminating said display panel;

a translucent back-projection type screen on a surface of which is formed a lenticular lens comprising a large number of stripe lenses arranged substantially in parallel;

a projection lens for projecting light supplied from said display panel onto said screen;

at least one mirror arranged between said projection lens and said screen; and

means for causing S polarized light to be incident upon said at least one mirror and for causing the light as reflected by said at least one mirror to be incident upon said screen in a direction of oscillation substantially perpendicular to the direction of the length of said stripe lenses.

3. A liquid crystal projector comprising:

liquid crystal display means;

a light source for illuminating said display means;

a translucent back-projection type screen on a surface of which is formed a lenticular lens comprising a large number of stripe lenses arranged substantially in parallel;

projection means for projecting light passing through said display means onto said screen; and

oscillating direction control means for receiving S polarized light from said projection means and for causing the light as received to be incident upon said screen in a direction of oscillation substantially perpendicular to the direction of length of said stripe lenses.

4. A liquid crystal projector according to claim 3, wherein said display means includes at least one polarizing plate for causing S polarized light to be incident upon said control means.

5. A liquid crystal projector comprising:

liquid crystal display means for displaying an image;

a light source for illuminating said display means;

a translucent back-projection type screen on a surface of which is formed a lenticular lens comprising a large number of stripe lenses arranged substantially in parallel;

projection means for projecting light supplied from said display means onto said screen;

oscillating direction control means for causing the light transmitted through said display means to be incident upon said screen in a direction of oscillation substantially perpendicular to the direction of length of said stripe lenses;

at least one mirror arranged between said projection means and said screen; and

means for causing S polarized light to be incident upon said at least one mirror.

6. A liquid crystal projector comprising:

a liquid crystal display means for displaying an image;

a light source for illuminating said display means;

a translucent back-projection type screen on a surface of which is formed a lenticular lens comprising a large number of stripe lenses arranged substantially in parallel;

projecting means for projecting light supplied from said display means onto said screen;

at least one mirror arranged between said projecting means and said screen; and

means for causing S polarized light to be incident upon said at least one mirror and for causing the light as reflected by said at least one mirror to be incident upon said screen in a direction of oscillation substantially perpendicular to the direction of the length of said stripe lenses.