ILLUMINATION DEVICE

• US 20130135856A1
• Filed: 06/08/2011
• Published: 05/30/2013
• Est. Priority Date: 08/12/2010
• Status: Active Grant

• Current Assignee: Japan Applied Optics Co., Ltd.,
• Original Assignee: Japan Applied Optics Co., Ltd.,
• Inventors: Arai, Shigeru
• Granted Patent: US 9,267,663 B2
• Time in Patent Office: Days
• US Class Current: 362/231
• CPC Class Codes: F21S 10/02 changing colors F21S10/002 - F21S10/007, F21S10/04 take precedence
• CPC Class Codes: F21V 14/02 by movement of light sources in vehicle head lamps F21S41/657
• CPC Class Codes: F21V 14/06 by movement of refractors in vehicle head lamps F21S41/635
• CPC Class Codes: F21V 14/08 by movement of the screens or filters
• CPC Class Codes: F21V 17/12 by screwing
• CPC Class Codes: F21V 17/164 the parts being subjected to bending, e.g. snap joints
• CPC Class Codes: F21V 29/77 with essentially identical diverging planar fins or blades, e.g. with fan-like or star-like cross-section
• CPC Class Codes: F21V 29/773 the planes containing the fins or blades having the direction of the light emitting axis
• CPC Class Codes: F21V 5/008 Combination of two or more successive refractors along an optical axis
• CPC Class Codes: F21V 5/04 of lens shape
• CPC Class Codes: F21V 7/0091 using total internal reflection
• CPC Class Codes: F21W 2131/304 for pictures
• CPC Class Codes: F21W 2131/406 for theatres, stages or film studios
• CPC Class Codes: F21Y 2105/10 comprising a two-dimensional array of point-like light-generating elements
• CPC Class Codes: F21Y 2105/12 characterised by the geometrical disposition of the light-generating elements, e.g. arranging light-generating elements in differing patterns or densities
• CPC Class Codes: F21Y 2113/10 of different colours
• CPC Class Codes: F21Y 2113/13 comprising an assembly of point-like light sources
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]

Abstract

Light having little color inconsistency is effectively emitted with a simple structure achieving favorable productivity. A plurality of multi-color light emitting diodes comprising a plurality of LED chips having different light emission colors is disposed on the same surface such that the light emitted by the plurality of the multi-color light emitting diodes is mixed and emitted in a illumination device, wherein at least one multi-color light emitting diode from among the plurality of multi-color light emitting diodes is disposed while being rotated by a prescribed angle with reference to one other multi-color light emitting diode in such a manner that when translating the one multi-color light emitting diode so as to overlap with the one other multi-color light emitting diode, LED chips having the same light emission color do not overlap with each other.

Claims

1-11. -11. (canceled)

12. An illumination device for mixing and radiating the light emitted by a plurality of multi-color light emitting diodes, wherein

the illumination device is provided with first lenses disposed correspondingly to each of said plurality of multi-color light emitting diodes in contact with or in the proximity of the front side thereof and a second lens disposed on the front side of the plurality of first lenses, and

said second lens has on the rear surface a corrugated sheet-like unevenly profiled portion formed by disposing a plurality of rows of recessed portions with concave shaped cross-section continuing in one direction in such a way that the degree of diffusion when light incident from the rear surface side is diffused and radiated from the front surface is set to be larger in the direction orthogonal to the direction in which said unevenly profiled portion continues on the rear surface than in the direction in which said unevenly profiled portion continues, and

the second lens is provided to rotate said unevenly profiled portion around the optical axis.

13. The illumination device according to claim 12, wherein said second lens has an unevenly profiled portion formed with a number of quadrangular pyramid-shaped recessed portions on the front surface.

14. The illumination device according to claim 12, further comprising a hood covering substantially cylindrically the front side of said second lens, wherein said hood has a shape with the front end portion being obliquely cutoff and is arranged rotatably around the optical axis of said second lens.

15. The illumination device according to claim 14, wherein the illumination device is formed by connecting a rear cylindrical portion having said multi-color light emitting diode and said first lens with a front cylindrical portion having said second lens and said hood, and

said front cylindrical portion includes a combining cylindrical portion detachably connected to said rear cylindrical portion, said hood extended over the periphery of the combining cylindrical portion, said second lens rotatably provided on the front end side in said combining cylindrical portion, and a frame shaped spring member provided on the rear side of the second lens in said combining cylindrical portion, and

an inward edge portion inwardly folded to contact the second lens from the front side is provided at the front edge of said combining cylindrical portion, and

an annular groove continuing throughout the circumference is formed on the inner peripheral surface of said hood, and

said frame shaped spring member has one part and one other part opposing said one part in the outer periphery respectively, each of which passes through said combining cylindrical portion to fit in said annular groove, and thereby said frame shaped spring member is latched with said combining cylindrical portion such that said frame shaped spring member elastically presses said second lens from the rear side while holding said hood rotatably and unmovably in the back-and-forth direction.

16. The illumination device according to claim 15, wherein the illumination device has a substrate for fixing in the same plane said plurality of multi-color light emitting diodes in such a manner that each of said plurality of multi-color light emitting diodes faces the front,

a body for covering the sides of said plurality of multi-color light emitting diodes and said substrate,

a heat sink disposed on the rear side of said substrate for dissipating the heat of said plurality of multi-color light emitting diodes, and

a support bracket for supporting said plurality of first lenses while fixing the same to said substrate.

17. The illumination device according to claim 16, wherein each of a plurality of multi-color light emitting diodes comprising a plurality of LED chips with different light emission colors, wherein at least one multi-color light emitting diode from among the plurality of multi-color light emitting diodes is disposed while being rotated by a prescribed angle with reference to one other multi-color light emitting diode in such a manner that when translating said one multi-color light emitting diode so as to overlap with said one other multi-color light emitting diode, LED chips having the same light emission color do not overlap with each other.

18. The illumination device according to claim 17, wherein four multi-color light emitting diodes are provided on the same circumference at regular intervals,

each of the multi-color light emitting diodes having LED chips with four colors of red, green, blue and white disposed on the same circumference at regular intervals, and each of the multi-color light emitting diodes is disposed while being rotated by 90 degrees with respect to the circumferentially adjoining multi-color light emitting diodes.

19. The illumination device according to claim 13, further comprising a hood covering substantially cylindrically the front side of said second lens, wherein said hood has a shape with the front end portion being obliquely cutoff and is arranged rotatably around the optical axis of said second lens.