Lighting device with linear light sources

• US 6,808,279 B2
• Filed: 01/16/2002
• Issued: 10/26/2004
• Est. Priority Date: 01/20/2001
• Status: Expired due to Fees

• Current Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Original Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Inventors: Greiner, Horst
• Primary Examiner(s): Cariaso, Alan
• Assistant Examiner(s): Tsidulko, Mark
• Application Number:
  US10/050,259
• Publication Number:
  US 20020097570A1
• Time in Patent Office: 1,014 Days
• Field of Search: 362/31, 362/26, 362/27, 362/29, 362/30, 362/223, 362/224, 362/307, 362/330, 362/339
• US Class Current: 362/30
• CPC Class Codes: G02B 6/0021 for housing at least a part of the light source, e.g. by forming holes or recesses
• CPC Class Codes: G02B 6/0055 Reflecting element, sheet or layer

Abstract

A lighting device is described with an optical waveguide plate that has a light emission surface and a plurality of channels each with at least one substantially linear light source. The device is suitable in particular for use as a backlight a liquid crystal display, such as an LCD picture screen, or for use as a planar light source. The channels are provided with a reflecting first layer at their upper sides facing the light emission surface. The coupling of light into the optical waveguide plate takes place through side walls of the channels.

Claims

1. A lighting device with an optical waveguide plate that has a light emission surface and a plurality of channels each for accommodating at least one substantially linear light source, wherein said channels are covered with a first reflecting layer at their upper sides facing the light emission surface, and the coupling of the light into the optical waveguide plate takes place through side walls of the channels,

wherein the optical waveguide plate includes a plurality of optical waveguide elements in which the channels are provided and which are optically fixedly connected to and extended from the lower side of the optical waveguide plate opposite to the light emission surface.

2. A lighting device with an optical waveguide plate that has a light emission surface and a plurality of channels each for accommodating at least one substantially linear light source, wherein:

the channels are covered with a first reflecting layer at their upper sides facing the light emission surface, and the coupling of the light into the optical waveguide plate takes place through side walls of the channels;

the channels are covered with a second reflecting layer at their lower sides opposite to the upper sides; and

the second reflecting layer extends over the lateral surfaces and the lower side of the optical waveguide plate.

3. The lighting device of claim 2, wherein the second reflecting layer has a spacing forming an air gap from the optical waveguide plate.

4. A liquid crystal display including the lighting device of claim 2.

5. A liquid crystal display including the lighting device of claim 3.

6. A lighting device with an optical waveguide plate that has a light emission surface and a plurality of channels each for accommodating at least one substantially linear light source, wherein:

the channels are covered with a first reflecting layer at their upper sides facing the light emission surface;

the coupling of the light into the optical waveguide plate takes place through side walls of the channels; and

the edges of the channels situated opposite the upper side are surrounded by a third reflecting layer.

7. A liquid crystal display including the lighting device of claim 6.