Illumination-panel for liquid crystal display of similar device

• US 4,043,636 A
• Filed: 08/01/1975
• Issued: 08/23/1977
• Est. Priority Date: 12/23/1974
• Status: Expired due to Term

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Eberhardt, Noel H., Keller, Ron F.
• Primary Examiner(s): Bauer, Edward S.
• Application Number:
  US05/600,979
• Time in Patent Office: 753 Days
• Field of Search: 350/127, 350/160 LC, 350/188, 350/259
• US Class Current: 349/65
• CPC Class Codes: G02F 1/133615 Edge-illuminating devices, i.e. illuminating from the side
• CPC Class Codes: G04G 9/0041 Illumination devices

Abstract

An illumination panel for the enhancement of image brightness of a liquid crystal display for a watch or similar device is disclosed. The panel has an internal light source with a suitably shaped and reflectorized coating to substantially direct internal and external light in the desired direction. More particularly, a transparent layer or member with an internal light source mounted at one end is selectively coated with a metallic reflecting material to reflect light from the internal source and from external sources through a crosshatched surface or a matte finished window on the surface of the member. The window may be defined by the reflectorized coating. The member is mounted adjacent to the exterior surface of the bottom substrate of the liquid crystal display. Diffused light is transmitted from the internal light source of the illumination panel through the bottom substrate of the display.

Claims

1. In a passive electro-optical display having a pair of substrates defining a volume, a liquid crystalline substance disposed in said volume, at least one of said substrates having electrodes disposed thereon to permit excitation of said liquid crystalline substance, the improvement comprising:

an edge lit light conductive body abutting one of said substrates to provide light conduction for illuminating said liquid crystalline substance, said light conductive body having a window with a surface formed into a plurality of subsurfaces, said plurality of subsurfaces forming a repetitive pattern of planar subsurfaces, and each subsurface being inclined with respect to at least one other subsurface of said plurality of subsurfaces;

a light source disposed adjacent to said light conductive body along an edge to provide illumination through said light conductive body generally parallel to said window and through said substrate to said liquid crystalline substance; and

a specular layer disposed on said light conductive body, to reflect light from said light source incident upon said light conductive body through said window.

2. The improvement of claim 1 wherein said repetitive pattern is a pattern employing a multiplicity of linear, planar subsurfaces.

3. The improvement of claim 2 wherein said subsurfaces are a first and second group of triangular prisms projecting from a basal plane, said prisms of said first group intersecting said prisms of said second group to form a crosshatched array.

4. The improvement of claim 1 wherein said plurality of subsurfaces is a first and second group of triangular prisms projecting from a basal plane, intersecting said prisms of said second group to form a cross-hatched array.

5. The improvement of claim 4 wherein:

said crosshatched array of triangular prisms form substantially perpendicular intersections, said window has a substantially rectangular perimeter and said prisms terminate at said perimeter to form an angle of approximately 45°

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