LENS ASSEMBLY

• US 20090067180A1
• Filed: 09/29/2006
• Published: 03/12/2009
• Est. Priority Date: 02/28/2006
• Status: Active Grant

• Current Assignee: Ghollam Tahmosybayat
• Original Assignee: Ghollam Tahmosybayat
• Inventors: Tahmosybayat, Ghollam
• Granted Patent: US 7,810,962 B2
• Time in Patent Office: Days
• US Class Current: 362/339
• CPC Class Codes: G02B 19/0028 refractive and reflective surfaces, e.g. non-imaging catadioptric systems
• CPC Class Codes: G02B 19/0061 the light source comprising a LED semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission H01L33/00
• CPC Class Codes: G02B 19/0071 adapted to illuminate a complete hemisphere or a plane extending 360 degrees around the source
• CPC Class Codes: G02B 3/00 Simple or compound lenses
• CPC Class Codes: H01L 33/58 Optical field-shaping elements

Abstract

A lens assembly (4) comprises a body (6) formed from a transparent material. The body (6) is mounted on an LED chip (8) comprising an LED (10). The LED (10) is disposed in a recess (12) formed in the body (6) such that the LED 10 is positioned on the longitudinal axis Z of the lens assembly (4). A convex lens (14) is formed in the aperture (12). The outer surface (16) of the lens assembly (4) comprises a plurality of flat surfaces in concentric rings that form a plurality of optical steps (18). The length of the respective steps increases towards the base (7) of the body (6). A central dimple (20) is disposed on axis Z. The dimple (20) prevents a black spot appearing when the lens assembly (4) is viewed along axis Z.

Claims

1. A lens assembly for redirecting light emitted by a light source, the lens assembly comprising:

an at least partially transparent body having a longitudinal axis and a recess for receiving a light source; and

a first surface disposed adjacent the recess and adapted to reflect a portion of light emitted by the light source such that said portion of light is emitted from the assembly transversely to said longitudinal axis, and wherein the first surface is adapted to transmit a further portion of light emitted by the light source such that said further portion of light is emitted from the assembly in a direction substantially parallel to said longitudinal axis.

2. An assembly according to claim 1, further comprising a second surface adapted to scatter light emitted by the assembly.

3. An assembly according to claim 2, wherein said second surface comprises a plurality of optical steps forming a Fresnel lens contour.

4. An assembly according to claim 3, wherein each optical step comprises a ring formed about the longitudinal axis and forms a deviating prism.

5. An assembly according to claim 3, wherein each said optical step has a different angle with respect to the longitudinal axis.

6. An assembly according to claim 2, wherein said second surface further comprises a dimple disposed on the longitudinal axis.

7. An assembly according to claim 1, wherein said first surface is substantially part spherical.

8. An assembly according to claim 1, wherein said body is rotationally symmetrical about the longitudinal axis.

9. An assembly according to claim 1, further comprising a reflective material disposed adjacent a base of the body.

10. An assembly according to claim 1, wherein the body comprises a flange portion.

11. An assembly according to claim 10, wherein said flange is formed integrally with the body.

12. An assembly according to claim 1, wherein the body is one of a glass, epoxy and polymeric material.

13. An assembly according to claim 1, wherein the body has a refractive index of between approximately 1.3 and approximately 1.7.

14. An assembly according to claim 13, wherein the body has a refractive index of approximately 1.53.

15. (canceled)

16. A lens assembly for redirecting light emitted by a light source, the lens assembly comprising:

an at least partially transparent body having a longitudinal axis, a recess and a flange, the recess receiving a light source, the body being rotationally symmetrical about the longitudinal axis, and the flange being integral with the body;

a substantially part spherical first surface disposed adjacent the recess and adapted to reflect a portion of light emitted by the light source such that the portion of light is emitted from the assembly transversely to the longitudinal axis, and wherein the first surface is adapted to transmit a further portion of light emitted by the light source such that the further portion of light is emitted from the assembly in a direction substantially parallel to the longitudinal axis;

a second surface adapted to scatter light emitted by the assembly, wherein the second surface comprises a plurality of optical steps creating a Fresnel lens contour and a dimple disposed on the longitudinal axis, each optical step comprising a ring about the longitudinal axis and creating a deviating prism, and wherein each of the optical steps has a different angle with respect to the longitudinal axis; and

a reflective material disposed adjacent a base of the body;

wherein the body has a refractive index of between approximately 1.3 and approximately 1.7.

17. An assembly according to claim 16, wherein the body is one of a glass, epoxy and polymeric material.

18. An assembly according to claim 16, wherein the body has a refractive index of approximately 1.53.