Lighting device

• US 9,435,508 B2
• Filed: 07/06/2012
• Issued: 09/06/2016
• Est. Priority Date: 07/11/2011
• Status: Active Grant

• Current Assignee: LG Innotek Company Limited (LG Corporation)
• Original Assignee: LG Innotek Company Limited (LG Corporation)
• Inventors: Lee, Dong Hyun, Seong, Dong Mug, Eom, Jun Phill, Hong, Beom Sun
• Primary Examiner(s): Alavi, Ali
• Application Number:
  US14/232,531
• Publication Number:
  US 20140168993A1
• Time in Patent Office: 1,523 Days
• Field of Search: 362/331
• US Class Current: 1/1
• CPC Class Codes: F21S 8/04 intended only for mounting on a ceiling or the like overhead structures F21S8/02 takes precedence; details of ceiling bases F21V21/03
• CPC Class Codes: F21V 5/004 using microlenses
• CPC Class Codes: F21Y 2105/00 Planar light sources
• 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 5/0278 used in transmission

Abstract

Disclosed is a light device comprising: a diffusion unit for diffusing and radiating light incident from a light source; and a condensing unit installed on a light radiating surface of the diffusion unit, including a micro lens array of lenses having sag determined depending on one of a light emitting area of the lighting device and total light flux of the lighting device. Thus, the lighting device can reduce a light flux emitted at the angle between 65 deg and 90 deg, thereby meeting UGR conditions.

Claims

1. A lighting device, comprising:

a light source unit;

a diffusion unit for diffusing light emitted from the light source unit; and

a condensing unit including a microlens array on a light emitting surface of the diffusion unit;

wherein the microlens array includes a plurality of lenses having a sag determined based on any one of a light emitting area and a total luminous flux, and

wherein the lenses of the plurality of lenses are spaced apart from each other.

2. The lighting device of claim 1, wherein the diffusion unit and the condensing unit are bonded so as to form a spaced part.

3. The lighting device of claim 2, further comprising a support frame between the diffusion unit and the condensing unit.

4. The lighting device of claim 2, further comprising an adhesive material interposed between the diffusion unit and the condensing unit.

5. The lighting device of claim 4, wherein a coating area of the adhesive material is less than 70% of a total area of the light emitting surface of the diffusion unit.

6. The lighting device of claim 2, further comprising a light diffusion member between the diffusion unit and the condensing unit.

7. The lighting device of claim 1, further comprising a roughness pattern having roughness on one surface or both surfaces of a surface of the diffusion unit and a surface of the condensing unit which are opposite to each other.

8. The lighting device of claim 1, wherein the sag ranges from 0.1 to 0.25.

9. The lighting device of claim 8, wherein a unified glare rating (UGR) is 19 or below.

10. The lighting device of claim 9, wherein the condensing unit enables the luminous flux emitted from the light source unit to be reduced at 65-90 degrees.

11. The lighting device of claim 10, wherein the condensing unit is disposed on a plate.

12. The lighting device of claim 11, wherein the plate contains any one material of polycarbonate (PC), polymethylmethacrylate (PMMA), and polyethylene terephthalate (PET).

13. The lighting device of claim 11, wherein the microlens array is made of a different material from that of the plate.

14. The lighting device of claim 13, wherein the microlens array is made of a photocurable or thermosetting resin.

15. The lighting device of claim 11, wherein the microlens array is directly formed on the plate.

16. A lighting device, comprising:

a light source unit;

a diffusion unit for diffusing light emitted from the light source unit;

a condensing unit including a microlens array on a light emitting surface of the diffusion unit; and

a light diffusion member between the diffusion unit and the condensing unit;

wherein the microlens array includes a plurality of lenses having a sag determined based on any one of a light emitting area and a total luminous flux,

wherein the diffusion unit and the condensing unit are bonded so as to form a spaced part, and

wherein the light diffusion member has a bead structure.

17. The lighting device of claim 16, wherein the light diffusion member is fixed by an adhesive material.

18. A lighting device, comprising:

a light source unit;

a diffusion unit for diffusing light emitted from the light source unit; and

a condensing unit on a light emitting surface of the diffusion unit;

wherein the condensing unit includes a first concave part on a first surface facing the light emitting surface of the diffusion unit,

wherein the condensing unit includes a plurality of lenses on a second surface opposite to the first surface, and

wherein the plurality of lenses has a sag determined based on any one of a light emitting area and a total luminous flux.

19. The lighting device of claim 18, wherein the diffusion unit includes a second concave part on the light emitting surface.