Liquid crystal projector

• US 5,473,339 A
• Filed: 05/19/1992
• Issued: 12/05/1995
• Est. Priority Date: 07/20/1989
• Status: Expired due to Term

• Current Assignee: Sanyo Electric Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Sanyo Electric Company Limited (Panasonic Holdings Corporation)
• Inventors: Kobayashi, Shigeru, Kaneko, Kenji, Fujiwara, Koichi, Hosoi, Kiyoshi, Funazo, Yasuo, Kono, Kazuhiro, Matsumura, Takao, Shiogai, Shinji, Otsuki, Shinichi, Miwa, Takashi, Hamagishi, Goro, Kishimoto, Shunichi, Kanatani, Keiichi
• Primary Examiner(s): Weldon, Ulysses
• Application Number:
  US07/885,693
• Time in Patent Office: 1,295 Days
• Field of Search: 353/34, 353/30, 353/31, 345/4, 345/87
• US Class Current: 345/87
• CPC Class Codes: H04N 9/3105 for displaying all colours simultaneously, e.g. by using two or more electronic spatial light modulators simultaneous projection in colour photography G03B33/10; beam splitting or combining systems per se G02B27/10
• CPC Class Codes: H04N 9/317 Convergence or focusing systems electronic adjustment of convergence H04N9/3185; convergence or focusing arrangements for cathode ray tubes H04N9/28; means for automatic focusing of projectors not peculiar to the presence of an electronic spatial light modulator G03B21/53

Abstract

In a liquid crystal projector having a light source and liquid crystal panel units disposed in the optical paths, reflecting means is disposed on the emanating side of the projector for reflecting the light in a direction approximately perpendicular to the optical axis, and change-over means is coupled to the liquid crystal panel units for reversing the lateral directions of images.

Claims

1. A liquid crystal projector comprising:

a light source;

separating means for separating light from the light source into three light components;

liquid crystal panel units disposed in respective optical paths for the three light components separated by the light separating means, each of the liquid crystal panel units to modulate the light component in accordance with image data, each of the liquid crystal panel units including

a) a liquid crystal panel disposed as inclined at a predetermined angle with a plane perpendicular to an optical path in accordance with a preference angle of field,

b) a condenser lens, and

c) an incident-side polarizing plate, said incident-side polarizing plate is arranged perpendicular to the optical path; and

optically composing means for optically composing the three light components as transmitted through the liquid crystal panel units.

2. A liquid crystal projector as defined in claim 1, wherein the predetermined angle of inclination of the liquid crystal panel is about 3 degrees.

3. A liquid crystal projector as defined in claim 1, wherein the condenser lens is arranged perpendicular to the optical path.

4. A liquid crystal projector as defined in claim 3, wherein the polarizing plate on an incident side is affixed to a rear surface of the condenser lens with a transparent silicon adhesive.

5. A liquid crystal projector as defined in claim 1, wherein on an emanating side of the optical composing means, a reflecting means is disposed for reflecting light composed by the optical composing means in a direction approximately perpendicular to an optical axis of the optical composing means;

and change-over means is coupled to each of the liquid crystal panel units for reversing a lateral direction of images in the liquid crystal panel units.

6. A liquid crystal projector as defined in claim 5 wherein the reflecting means is removable, and the change-over means is on-off controllable.

7. A liquid crystal projector as defined in claim 1 wherein the light source is insertable inside a generally parabolic reflector through an opening formed in the reflector centrally thereof, and the light source comprises an end member having an outwardly projecting stepped portion and removably attachable to the reflector with the stepped portion in bearing contact with the opening end of the reflector, and a lamp connected to the end member and having a light-emitting portion positioned at the focal point of the reflector.