SYSTEM AND METHOD FOR PROVIDING A UNIFORM BACKLIGHT

• US 20080080180A1
• Filed: 06/06/2007
• Published: 04/03/2008
• Est. Priority Date: 06/07/2006
• Status: Active Grant

• Current Assignee: Omron Corporation
• Original Assignee: Siemens Energy & Automation Incorporated (Siemens AG)
• Inventors: Messina, Michael, Dunn, Sheila
• Granted Patent: US 7,731,391 B2
• Time in Patent Office: Days
• US Class Current: 362/235
• CPC Class Codes: F21S 2/005 of modular construction
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: G01N 21/8806 Specially adapted optical and illumination features
• CPC Class Codes: Y10T 29/49002 Electrical device making

Abstract

An illumination system includes an illumination source such as an array of LED'"'"'s over which is provided a diffuser. The illumination source provides light which, because of light refraction, radiates generally uniformly from edge to edge of the diffuser. The diffuser may be a planar flat piece of may include a hollow, cup like structure formed by a frame with a cover. The illumination system may be scaled up to provide multiple such illumination devices side by side to provide a greater area or strength of illumination. Multiple systems may utilize multiple diffusers or a single diffuser covering multiple illumination sources. The illumination source may be mounted to a backplate or heatsink which is larger than the illumination source to facilitate the addition of further electronic circuitry and or mounting capabilities.

Claims

1. An illumination system providing generally uniform illumination from edge to edge, said illumination system comprising:

at least one illumination device, said at least one illumination device comprising;

a source of illumination; and

a diffuser, disposed proximate said source of illumination and between said source of illumination and an object to be illuminated, said diffuser including a generally planar surface and disposed a spaced distance from said source of illumination, said diffuser configured for radiating light from said source of illumination through generally at least said entire planar surface of said diffuser.

2. The illumination system of claim 1, wherein said diffuser comprises a frame including a left side, right side, top side and bottom side, said frame having a height, said diffuser including a generally planar cover extending between all said sides and having a length and a width, said cover disposed a spaced distance away from said source of illumination corresponding to said height of said frame, said sides and cover of said diffuser forming a hollow cup like structure for radiating light from said source of illumination through generally at least said entire planar surface of said cover.

3. The illumination system of claim 1, wherein said illumination system includes a plurality of said illumination devices mounted edge to edge to create a single larger illumination system of generally uniform illumination.

4. The illumination system of claim 1, wherein said diffuser is generally the same size as said source of illumination.

5. Illumination system of claim 1, wherein said source of illumination includes a back plate to which said source of illumination is mounted, and wherein said backplate has a width and a length which is generally the same as a length and width as said source of illumination.

6. The illumination system of claim 5, wherein said backplate is larger than said source of illumination along at least one of said length and width of said backplate.

7. The illumination system of claim 1, wherein said source of illumination is a single illumination element.

8. The illumination system of claim 1, wherein said source of illumination is a multiple illumination element.

9. The illumination system of claim 8, wherein said multiple illumination elements include a plurality of LED elements.

10. The illumination system of claim 9, wherein said plurality of LED elements are mounted together as an LED module.

11. The illumination system of claim 1, wherein said diffuser is made of a light transmissive material.

12. A method of illuminating an object, said method comprising the acts of:

determining an amount of illumination required for illuminating an object; and

selecting one or more illumination devices for generally uniformly illuminating said object, each of said one or more illumination devices comprising;

a source of illumination; and

a diffuser, disposed proximate said source of illumination and between said source of illumination and an object to be illuminated, said diffuser including a generally planar surface and disposed a spaced distance from said source of illumination, said diffuser configured for radiating light from said source of illumination through generally at least said entire planar surface of said diffuser.

13. The method of claim 12, wherein each said diffuser comprises a frame including a left side, right side, top side and bottom side, said frame having a height, said diffuser including a generally planar cover extending between all said sides and having a length and a width, said cover disposed a spaced distance away from said source of illumination corresponding to said height of said frame, said sides and cover of said diffuser forming a hollow cup like structure for radiating light from said source of illumination through generally at least said entire planar surface of said cover.

14. The method of claim 12, wherein said act of selecting one or more illumination devices includes selecting a plurality of said illumination devices and further including the act of placing each of said plurality of illumination devices edge to edge, proximate and generally in contact with one another, to provide generally uniform illumination of said object.