COLLECTION OPTICS FOR LED ARRAY WITH OFFSET HEMISPHERICAL OR FACETED SURFACES

• US 20110063840A1
• Filed: 09/29/2010
• Published: 03/17/2011
• Est. Priority Date: 10/31/2003
• Status: Active Grant

• Current Assignee: Phoseon Technology, Inc.
• Original Assignee: Phoseon Technology, Inc.
• Inventors: Jasmin, Roland JR., Anderson, Duwayne R.
• Granted Patent: US 8,523,387 B2
• Time in Patent Office: Days
• US Class Current: 362/237
• CPC Class Codes: F21V 5/007 Array of lenses or refractors for a cluster of light sources, e.g. for arrangement of multiple light sources in one plane combination of two or more refractors F21V5/008
• CPC Class Codes: F21V 5/04 of lens shape
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: G02B 3/0056 arranged along two different directions in a plane, e.g. honeycomb arrangement of lenses G02B3/0043 takes precedence; miniaturised objectives for electronic devices employing wafer level optics G02B13/0085
• CPC Class Codes: G02B 5/045 Prism arrays
• CPC Class Codes: H01L 33/58 Optical field-shaping elements

Abstract

An array of LEDs is provided having a lens array for collecting divergent light from each LED. Each lens in the array is associated with a respective LED and has a compound shape including a curved surface that may be spherical or may have an offset aspherical shape. The curved surfaces are centered about each side of its associated LED. The lens may alternatively include faceted surfaces that approximate the curved lens surface.

Claims

1. A lens array, comprising:

multiple lenses in a monolithic structure, for collecting light from an array of multiple LED light sources;

wherein each LED light source emits divergent light,

wherein for each LED light source there is a lens having a first surface with a compound shape of at least two faceted portions separated by a flat portion that is distributable around the LED light source and arranged to collimate the light from the LED, wherein each faceted portion is centered about a radius R extending from a center point that lies directly above an imaginary light point source on one side of the LED with each faceted portion centered over the imaginary light point source on each side, and

wherein each lens approximates a spherical or an aspheric shape relative to its respective LED light source.

2. The lens array of claim 1, wherein the faceted portions are equidistant from the center line of the LED light source and the flat portion is perpendicular to the center line.

3. The lens array of claim 1, wherein each of the offset spherical or aspheric shapes are offset from a center line extending through the each LED light source.

4. The lens array of claim 1, wherein each of the lenses is symmetric about a center line extending through each LED light source.

5. The lens array of claim 1, wherein each of the lenses includes sections that collect light from respective portions of each LED light source.

6. The lens array of claim 5, wherein each lens section is optimized for each portion of each LED light source from which each section collects light.

7. The lens array of claim 1, wherein each of the lenses includes an offset aspheric shape.

8. The lens array of claim 1, wherein each of the faceted surfaces has a symmetrically circular shape.

9. The lens array of claim 1 wherein each of the faceted surfaces has a square tile pattern.

10. The lens array of claim 9, wherein the square tile pattern fully fills a surface of each of the lenses.

11. The lens array of claim 9, wherein the square tile pattern is formed from micro-pyramids.

12. A method of manufacturing an LED light module, comprising:

determining a configuration for an array of lenses so that there is a separate lens for each LED,

wherein each lens has a first surface having a compound shape including a faceted portion that is distributed around an LED arranged to collimate the light from the LED, and

wherein each lens having a compound shape that includes faceted portions separated by a flat portion,

the lens being disposed over an LED so that light from each side of the LED is projected into a respective faceted surface; and

each faceted portion is centered about a radius R extending from a center point that lies directly above an imaginary light point source on each one side of the LED with each faceted portion centered over the imaginary light point source on each side so that each faceted portion is effectively a plano-convex lens centered over a side of the LED.

13. The method of claim 12, wherein the lens array is monolithically molded.

14. The method of claim 12, wherein each lens in the lens array is fabricated by machining faceted surfaces into the lens array.

15. The method of claim 14, wherein the shape of the lens array is formed by machining a mold using a drill bit-type tool.

16. The method of claim 15, wherein each lens in the lens array is machined using a circularly symmetric pattern.

17. The method of claim 14, wherein the shape of the lens array is formed by machining a mold using a surface lathe, router, or grinder.

18. The method of claim 17, wherein each lens in the lens array is machined using micro-pyramids in a square tile pattern.

19. The method of claim 13, wherein the lens array is formed by molding potting gel.

20. The method of claim 12, wherein the lens array is formed of glass.

21. The method of claim 20, wherein each lens in the lens array is circularly symmetric.

22. The method of claim 21, wherein each lens in the lens array is formed of micro-pyramids in a square tile pattern.