LIGHT-EMITTING DEVICE AND A LENS THEREOF

Abstract

A lens includes a lens body having a bottom surface, a reflective surface, and a refractive surface. The bottom surface is to be disposed proximate to a light-emitting component. The reflective surface is disposed opposite to the bottom surface along a lens axis, and reflects a first portion of the light provided by the light-emitting component that is incident thereon toward the refractive surface. The refractive surface extends from an edge of the reflective surface to the bottom surface, and refracts a second portion of the light provided by the light-emitting component that is incident thereon as well as the first portion of the light reflected by the reflective surface theretoward in sideward directions relative to the light-emitting component. The lens body has cross-sections transverse to the lens axis, sizes of which increase gradually from a junction of the reflective surface and the refractive surface toward the bottom surface.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

Other features and advantages of the present invention will become apparent in the following detailed description of the preferred embodiments with reference to the accompanying drawings, of which:

FIG. 1 is a schematic view of a lens in the prior art;

FIG. 2 is a schematic view of another lens in the prior art;

FIG. 3 is a schematic view of the first preferred embodiment of a light-emitting device according to the present invention;

FIG. 4 is a plot illustrating results of an experiment conducted to test the efficiency of the first preferred embodiment;

FIG. 5 is a flow chart showing steps of a first method for making the light-emitting device according to the first preferred embodiment;

FIG. 6 is a schematic diagram illustrating the first method;

FIG. 7 is a flow chart showing steps of a second method for making the light-emitting device according to the first preferred embodiment;

FIG. 8 is a schematic diagram of a lens cap used in the second method;

FIG. 9 is a flow chart showing steps of a third method for making the light-emitting device according to the first preferred embodiment;

FIG. 10 is a schematic view of the second preferred embodiment of a light-emitting device according to the present invention;

FIG. 11 is an enlarged fragmentary view showing a reflective surface of a lens according to the second preferred embodiment;

FIG. 12 is a plot illustrating results of an experiment conducted to test the efficiency of the second preferred embodiment;

FIG. 13 is a schematic view of the third preferred embodiment of a light-emitting device according to the present invention; and

FIG. 14 is a plot illustrating results of an experiment conducted to test the efficiency of the third preferred embodiment.

Claims

1. A lens for directing light provided by a light-emitting component sideways, said lens comprising a lens body having a bottom surface, a reflective surface, and a refractive surface, wherein: said bottom surface is to be disposed proximate to the light-emitting component;said reflective surface is disposed opposite to said bottom surface along a lens axis, and reflects a first portion of the light provided by the light-emitting component that is incident thereon toward said refractive surface;said refractive surface extends from an edge of said reflective surface to said bottom surface, and refracts a second portion of the light provided by the light-emitting component that is incident thereon as well as the first portion of the light reflected by said reflective surface theretoward in sideward directions relative to the light-emitting component; andsaid lens body has cross-sections transverse to the lens axis, sizes of which increase gradually from a junction of said reflective surface and said refractive surface toward said bottom surface.

2. The lens as claimed in claim 1, wherein said lens body has upper and lower body parts, a projection of an outer periphery of said upper body part on said bottom surface being completely surrounded by a projection of an outer periphery of said lower body part on said bottom surface.

3. The lens as claimed in claim 1, wherein said refractive surface is a curved surface.

4. The lens as claimed in claim 1, wherein said reflective surface is provided with a reflective coating layer, said reflective coating layer being one of a completely optically non-transmissive layer and a partially optically transmissive layer.

5. The lens as claimed in claim 1, wherein said reflective surface is a wavy surface.

6. The lens as claimed in claim 5, wherein said lens body is symmetrical about the lens axis, said wavy surface including consecutive wave segments having amplitudes that are measured with respect to the lens axis and that increase in a direction away from said bottom surface.

7. A lens for directing light provided by a light-emitting component sideways, said lens comprising a lens body having a bottom surface, a wavy surface, and a refractive surface, wherein: said bottom surface is to be disposed proximate to the light-emitting component;said wavy surface is disposed opposite to said bottom surface along a lens axis, and is capable of reflecting a first portion of the light provided by the light-emitting component that is incident thereon toward said refractive surface; andsaid refractive surface extends from an edge of said wavy surface to said bottom surface, and refracts a second portion of the light provided by the light-emitting component that is incident thereon as well as the first portion of the light reflected by said wavy surface theretoward in sideward directions relative to the light-emitting component.

8. The lens as claimed in claim 7, wherein said refractive surface is a curved surface.

9. The lens as claimed in claim 7, wherein said wavy surface has a plurality of steps such that said wavy surface is configured with a ladder-shaped cross section parallel to the lens axis.

10. The lens as claimed in claim 7, wherein said lens body is symmetrical about the lens axis, said wavy surface including consecutive wave segments having amplitudes that increase in a direction away from said bottom surface.

11. A light-emitting device, comprising a base, a light-emitting component, and a lens, wherein: said light-emitting component is mounted on said base; andsaid lens directs light emitted by said light-emitting component sideways, said lens including a lens body that has a bottom surface, a reflective surface, and a refractive surface, said bottom surface being disposed proximate to said light-emitting component, said reflective surface being disposed opposite to said bottom surface along a lens axis, and reflecting a first portion of the light provided by said light-emitting component that is incident thereon toward said refractive surface, said refractive surface extending from an edge of said reflective surface to said bottom surface, and refracting a second portion of the light provided by said light-emitting component that is incident thereon as well as the first portion of the light reflected by said reflective surface theretoward in sideward directions relative to said light-emitting component, said lens body having cross-sections transverse to the lens axis, sizes of which increase gradually from a junction of said reflective surface and said refractive surface toward said bottom surface.

12. The light-emitting device as claimed in claim 11, wherein said lens body has upper and lower parts, a projection of an outer periphery of said upper body part on said bottom surface being completely surrounded by a projection of an outer periphery of said lower body part on said bottom surface.

13. The light-emitting device as claimed in claim 11, wherein said refractive surface of said lens is a curved surface.

14. The light-emitting device as claimed in claim 11, wherein said reflective surface is provided with a reflective coating layer.

15. The light-emitting device as claimed in claim 11, wherein said reflective surface has a plurality of steps such that said reflective surface is configured with a ladder-shaped cross section parallel to the lens axis.

16. The light-emitting device as claimed in claim 11, wherein said reflective surface is a wavy surface.

17. The light-emitting device as claimed in claim 16, wherein said lens body is symmetrical about the lens axis, said wavy surface including consecutive wave segments having amplitudes that are measured with respect to the lens axis and that increase in a direction away from said bottom surface.

18. A light-emitting device comprising a base, a light-emitting component, and a lens, wherein: said light-emitting component is mounted on said base; andsaid lens directs light emitted by said light-emitting component sideways, said lens including a lens body that has a bottom surface, a wavy surface and a refractive surface,said bottom surface being disposed proximate to the light-emitting component,said wavy surface being disposed opposite to said bottom surface along a lens axis, and being capable of reflecting a first portion of the light provided by said light-emitting component that is incident thereon toward said refractive surface,said refractive surface extending from an edge of said wavy surface to said bottom surface, and refracting a second portion of the light provided by said light-emitting component that is incident thereon as well as the first portion of the light reflected by said wavy surface theretoward in sideward directions relative to the light-emitting component.

19. The light-emitting device as claimed in claim 18, wherein said refractive surface is a curved surface.

20. The light-emitting device as claimed in claim 18, wherein said wavy surface is provided with a reflective coating layer.

21. The light-emitting device as claimed in claim 18, wherein said wavy surface has a plurality of steps such that said wavy surface is configured with a ladder-shaped cross section parallel to the lens axis.

22. The light-emitting device as claimed in claim 18, wherein said lens body is symmetrical about said lens axis, said wavy surface including consecutive wave segments having amplitudes that increase in a direction away from said bottom surface.