Liquid crystal projector

• US 4,671,634 A
• Filed: 02/05/1986
• Issued: 06/09/1987
• Est. Priority Date: 03/19/1985
• Status: Expired due to Term

• Current Assignee: Casio Computer Company Limited
• Original Assignee: Casio Computer Company Limited
• Inventors: Shibazaki, Shigeru, Kizaki, Masaharu
• Primary Examiner(s): HAROIAN, HARRY
• Application Number:
  US06/826,119
• Time in Patent Office: 489 Days
• Field of Search: 353/121, 353/122, 353/38, 353/69, 353/70, 353/81, 350/331, 350/333, 350/334, 350/452, 350/436, 350/127
• US Class Current: 353/122
• CPC Class Codes: G02F 1/133526 Lenses, e.g. microlenses or Fresnel lenses
• CPC Class Codes: G03B 21/006 using LCD's
• 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 which comprises image light-refracting means for deflecting the direction in which ligh beams permeating liquid crystal display panel is projected on a screen by an angle corresponding to the suitable viewing angle of the liquid crystal display panel, and wherein image light thus refracted is thrown on a screen in an enlarged form by means of projection lens systems.

Claims

1. A light crystal projector comprising:

lighting means;

transparent TN type liquid crystal display panel means for projecting an image illuminated by the light supplied from said lighting means toward a screen, said display panel means having a characteristic viewing angle deviating from a direction perpendicular to its plane at which an image displayed thereon can be observed in the brightest form;

image light-refracting means for deflecting the direction in which an image light permeating the liquid crystal display panel is to be projected toward the screen by an angle corresponding to the viewing angle of said display panel means so that the deflected direction is substantially the same as the perpendicular direction; and

projection lens means which is set on the optical axis between said liquid crystal display panel means and a screen to throw an image from the liquid crystal display panel means onto the screen in an enlarged form.

2. The liquid crystal projector according to claim 1, wherein said image light refracting means is formed of a Fresnel lens.

3. The liquid crystal projector according to claim 2, wherein said Fresnel lens is laminated over said liquid crystal display panel means while facing said lighting means.

4. The liquid crystal projector according to claim 2, wherein said Fresnel lens is laminated over said liquid crystal display panel while facing said screen.

5. The liquid crystal projector according to claim 1, wherein said image light refracting means is formed of an eccentric convex lens.

6. The liquid crystal projector according to claim 1, which further comprises:

lens means provided between said lighting means and liquid crystal display panel means to project image light beams delivered from the lighting means on the liquid crystal display panel means in the parallel form.

7. The liquid crystal projector according to claim 1, which further comprises an infrared ray absorbing filter which is interposed between said lighting means and liquid crystal display panel means to absorb infrared rays contained in a light projected from said lighting means.