WO2015011105A1

WO2015011105A1 - A lens for a light source

Info

Publication number: WO2015011105A1
Application number: PCT/EP2014/065650
Authority: WO
Inventors: Jing Lin; Wei Xiong; Junhua Zeng; Hongwei Zhang
Original assignee: Osram GmbH
Current assignee: Osram GmbH
Priority date: 2013-07-22
Filing date: 2014-07-21
Publication date: 2015-01-29
Anticipated expiration: 2016-01-22
Also published as: CN104197275A

Abstract

The present invention relates to a lens for a light source. The lens comprises a bottom surface and a protruding surface bulging from the bottom surface, the bottom surface comprises a recessed region, and a surface of the recessed region is configured as an incident surface, wherein the protruding surface comprises: a first sub region, by which first light from the light source is refracted to emerge and form first emergent light; a second sub region, by which second light from the light source is reflected and refracted to form second emergent light; and a third sub region, by which third light from the light source is reflected and refracted to form third emergent light.

Description

A Lens for a Light Source Technical Field

The present invention relates to a lens for a light source.

Background Art

The LED technology as an illumination technology with high efficiency, energy saving and long service lifetime presently is widely used in the illuminating device. The LED technology can be used to realize the conventional illumination effects such as that of incandescent lamp or fluorescent lamp, and for instance, is used for a streetlamp on the road, spotlight in the store or for indoor lighting. To use the LED illumina- tion technology in these circumstances not only can ensure sufficient light emitting intensity of the light source, but also can meet the user' s requirements to the illumination scope of the illuminating device. In addition, since the LED chip essentially illuminates directionally, that is, light emitted from the LED chip is mainly focused in one direction, further structure or device is needed in order to realize om- ni-directional illumination based on the use of the LED chip.

Summary of the Invention

In order to solve the above technical problem, the present invention provides a novel lens for a light source. The lens according to the present invention not only reduces the whole cost of the illuminating device due to its use of the materi^¬ al at a low cost, but also enables the light from the light source, after passing through the lens, to realize the omni- directional illumination effect with only a single such lens owing to the novel structural design of the lens. The object of the present invention is accomplished via such a lens for a light source. The lens comprises a bottom sur^¬ face and a protruding surface bulging from the bottom surface, the bottom surface comprises a recessed region, and a surface of the recessed region is configured as an incident surface, wherein, the protruding surface comprises: a first sub region, by which first light from the light source is re^¬ fracted to emerge and form first emergent light; a second sub region, by which second light from the light source is re- fleeted and refracted to form second emergent light; and a third sub region, by which third light from the light source is reflected and refracted to form third emergent light. With the help of emergent light from different regions of the same lens, the possibility of multidirectional or omni-directional illumination can be realized.

According to the solution of the present invention, the first emergent light, the second emergent light and the third emer^¬ gent light form omni-directional illumination. By virtue of the emergent light of the three parts, the effect of multidi- rectional or omni-directional illumination can be realized using the lens.

Preferably, the first emergent light mainly provides side il^¬ lumination, the second emergent light mainly provides back^¬ ward illumination and the third emergent light mainly pro- vides forward illumination. The possibility of omni^¬ directional illumination can be realized, and providing dif^¬ ferent and combined emergent light with different regions of the lens .

According to the solution of the present invention, the first sub region, the second sub region and the third sub region are arranged in sequence from the bottom surface in a bulging direction. With such arrangement, not only the occupation area of the lens can be reduced in a transverse direction, but also the light distribution characteristic of the light source can be used to make full use of the light from the light source to realize high optical efficiency.

According to the solution of the present invention, the second sub region comprises first surfaces and second surfaces arranged alternately in groups, wherein a part of the second light, after being reflected by the first surfaces, emerges through the second surfaces to form a part of the second emergent light. With the help of the different surfaces of the second sub region, it can be realized that emergent light in different directions can be emitted in the same region and, for instance, in a side direction, so as to increase the illumination range which can be covered by the emergent light emitted from the lens to ensure realization of the omni^¬ directional illumination effect.

Preferably, a part of the second light, after being reflected by the second surfaces, emerges through the first surfaces to form the other parts of the second emergent light. After re^¬ flected and turned around, one part of the second light can emerge through the first surfaces in a certain direction to form illumination effect.

Preferably, the first surface and the second surface of each group form a predetermined angle. According to such predeter^¬ mined angle, the illumination effect of different directions can be finally formed using different surfaces of the same group and wide-range coverage is accomplished.

According to the solution of the present invention, the third sub region comprises a third surface and a fourth surface, wherein a part of the third light, after being reflected by the third surface, emerges through the fourth surface to form a part of the third emergent light. Based on the different surfaces of the third sub region, the third light can emerge in different directions and finally form wide-range illumina^¬ tion, wherein the illumination effect in a certain direction can be formed with the aid of the light emerging from the fourth surface.

Preferably, a part of the third light, after being reflected by the fourth surface, emerges through the third surface to form the other parts of the third emergent light. The illumi^¬ nation effect in a further direction can be formed with the aid of the light emerging from the third surface.

Preferably, the fourth surface is configured in such a manner that the third light, after reflected by the fourth surface, forms the other parts of the converged third emergent light. According to such configuration, the converged light formed upon reflection of the fourth surface can meet the require^¬ ment to high light intensity in a particular direction. According to the solution of the present invention, viewed in a cross section perpendicular to the bottom surface and pass^¬ ing through the optical axis of the lens, the first sub re^¬ gion is configured to gradually get close to the optical axis from the bottom surface in the bulging direction. In this way, the first light, after passing through the first sub re^¬ gion, can be refracted and guided to, for instance, the side direction of the lens to form the illumination effect.

Preferably, the first sub region has a spline profile in the cross section. Such configuration not only can enable the first light, after effectively refracted, to emit to a prede- termined direction, and also can provide a design easily ma^¬ chined and manufactured.

According to the solution of the present invention, viewed in the cross section perpendicular to the bottom surface and passing through the optical axis of the lens, the first sur^¬ face is configured to gradually go away from the optical axis along a bulging direction, and the second surface is configured to gradually get close to the optical axis along the bulging direction. Therefore, two surfaces facing different directions are formed, and it is possible to guide the second light to different directions so as to realize the wide-range illumination coverage.

Preferably, the first surfaces and the second surfaces have a spline profile in the cross section. Such configuration not only can enable the second light, after effectively reflected by different surfaces, to emit to different predetermined di^¬ rections, but also provides the design which is easily ma^¬ chined and manufactured.

According to the solution of the present invention, viewed in the cross section perpendicular to the bottom surface and passing through the optical axis of the lens, the third sur^¬ face is configured to gradually get close the optical axis in the bulging direction, and the fourth surface is configured to gradually go away from the optical axis in the bulging di- rection. Thus, two surfaces facing different directions are formed, and the possibility of guiding the third light to different directions so as to realize the wide-range illumi^¬ nation coverage is provided.

Preferably, the third surface and the fourth surface have a spline profile in the cross section. Such configuration not only can enable the third light, after effectively reflected by different surfaces, to emit to different predetermined di^¬ rections, but also provides the design which is easily ma^¬ chined and manufactured. Preferably, the lens is configured rotationally symmetric. Thus, the light distribution of the emergent light which is finally rotationally symmetric can be realized.

Preferably, the recessed region is configured with a hemi^¬ spherical profile. According to such configuration, light from the light source can be incident in the lens from the recessed region, for instance, at a vertical incident angle, so as to realize the possibility of ensuring high optical ef^¬ ficiency .

Preferably, the lens is made of a transparent optical plastic or glass. Such lens has a low cost, is easily machined and manufactured, and ensures good mechanical performance and op^¬ tical performance.

Brief Description of the Drawings

The accompanying drawings constitute a part of the present Description and are used to provide further understanding of the present invention. Such accompanying drawings illustrate the embodiments of the present invention and are used to de^¬ scribe the principles of the present invention together with the Description. In the accompanying drawings the same compo- nents are represented by the same reference numbers. As shown in the drawings :

Fig. 1 is a sectional view of a lens according to the present invention; and Fig. 2 is a schematic diagram of optical path of the lens ac^¬ cording to the present invention.

Detailed Description of the Embodiments

As shown in Fig. 1, Fig. 1 shows a sectional view of a lens 100 according to the present invention. According to such configuration, the lens 100 on the whole is configured rota- tionally symmetric so as to meet the requirement that light from a light source 1, after passing through the lens 100, can finally form rotationally symmetrical light distribution of emergent light. Moreover, the lens 100 has a tree-shaped contour, light from the light source 1 distribute in 360 de^¬ grees around the illuminating device having the lens 100, the lens 100 is configured to be made of, for instance, an opti^¬ cal plastic or glass, which not only has a low cost but also ensures highly effective and reliable optical performance of such lens 100.

As shown in Fig. 1, the lens 100 comprises a bottom surface 2 and a protruding surface 3 with three different regions, first sub region 31, second sub region 32 and third sub re- gion 33, respectively. Besides, a light source 1 is disposed at the center of the bottom surface 2 of the lens 100. Such light source 1 can be configures as, for example, an LED light source, so as to realize advantages such as high effi^¬ ciency, energy saving and long service lifetime. In a direc- tion facing away from the light source 1, the bottom surface 2 further comprises a recessed region 4, which recessed re^¬ gion 4 can be configured, for instance, in a hemispherical shape, and then light from the light source 1 received in the recessed region 4 can be incident upon a surface of the re- cessed region 4 at a vertical incident angle, and enters the lens 100 taking the surface of the recessed region 4 as an incident surface 5. Besides, it is also shown in Fig. 1 that the first sub region 31 of the lens 100 can be configured, for instance, to have only one surface as an emergent surface, in this way, first light LI from the light source 1 can be directly refracted and emerge after passing through the first sub region 31. In the above, as viewed in cross section, the first sub region

31 can be configured with a spline profile so as to ensure highly effective optical performance and meet the requirement to the light distribution of the emergent light, and to be machined and fabricated at a low cost . The second sub region

32 and the third sub region 33 each have, for instance, two surfaces, wherein the second sub region 32 can be provided in groups, that is, there are multiple groups of the second sub regions 32, and each group has a first surface 321 and a se- cond surface 322, and the first surface 321 and the second surface 322 form a predetermined angle therebetween, and then, as shown in Fig. 2, viewed in the cross section, a profile having with multiple sharp corners in tooth shape, for example, can be formed on the circumference of the lens. The multiple groups of the second sub regions 32 can be config^¬ ured, for example, to stack along a direction of an optical axis X, that is, viewed in the cross section, the first sur^¬ face 321 and the second surface 322 can be configured with a spline profile, and multi-layered of structure with a tooth profile, for instance, is formed on the circumference of the lens 100, consequently, the light distribution characteristic of the light source 1 can be fully used to collect light from the light source 1, , second light L2 from the light source 1 is guided to different directions so as to finally realize the wide-range illumination effect, for instance, mainly in a backward direction.

The third sub region 33 is further configured in the top area of the lens 100, and such third sub region 33 is configured _

y

with two different surfaces, a third surface 331 and a fourth surface 332, and third light L3 from the light source 1 can be guided by the third surface 331 and the fourth surface 332 to different directions so as to realize the illumination ef- feet, for instance, mainly in the forward direction. In the above, the third surface 331 and the fourth surface 332 also can be configured with a spline profile, and viewed in cross section, the third surface 331 gradually gets close to the optical axis X of the lens 100, and the fourth surface 332 gradually goes away from the optical axis X in a direction from the bottom surface 2 to the protruding surface 3.

Fig. 2 shows a schematic diagram of optical path of the lens 100 according to the present invention. As shown in Fig. 2, the first light LI from the light source 1 emerges after passing through the first sub region 31 of the lens 100. The first sub region 31 can be configured with a profile having a spline curve, in this way, the first light LI can be directly refracted to form first emergent light LI' which provides il^¬ lumination of the lens mainly in the side direction, and also in the backward direction, and ensures to meet the illumina^¬ tion effect of a part of omni-direction of the lens 100.

The second light L2 from the light source 1 emerges after passing through the second sub region 32 of the lens 100. The second sub region 32 also can be configured with a spline profile, wherein the second sub region 32 comprises two sur^¬ faces facing different directions, the first surface 321 and the second surface 322, and the first surface 321 and the se^¬ cond surface 322 both can realize the reflective and refrac^¬ tive effects, respectively, that is, for instance, one part of the second light L2 turns to emit towards the second sur^¬ face 322 after being reflected by the first surface 321, and emerges after being confronted with and refracted by the se- cond surface 322. Similarly, the other part of the second light L2 turns to emit towards the first surface 321 after being reflected by the second surface 322, and emerges after being confronted with and refracted by the first surface 321. In this way, second emergent light L2' having wide-range il^¬ lumination effect in different directions is finally formed by means of the second sub region 32. Such second emergent light L2' specifically can emerge in a backward direction, and then the illumination effect in the backward direction among the omni-direction is formed, and also a few part of the second emergent light L2' forms illumination in the side direction .

The third light L3 of the light source 1 forms third emergent light L3' after emerging from the third sub region 33 of the lens 100. The third sub region 33 comprises two surfaces fac^¬ ing different directions, the third surface 331 and the fourth surface 332. Similar to the second sub region, the third light L3 is guided by the two surfaces to emerge from different directions. In other words, for instance, one part of the third light L3 turns to emit towards the fourth sur^¬ face 332 after being reflected by the third surface 331, and emerges after being confronted with and refracted by the fourth surface 332, similarly, the other part of the third light L3 turns to emit towards the third surface 331 after being reflected by the fourth surface 332, and emerges after being confronted with and refracted by the further surface 33. In this way, third emergent light L3' having wide-range illumination effect in different directions is finally formed by means of the third sub region 33. Such third emergent light L3' specifically can emerge in a forward direction, and then the illumination effect in the forward direction among the omni-direction is formed, and also a few part of the se^¬ cond emergent light L2' forms illumination in the side direc- tion. Additionally, the first surface 321 and the second sur^¬ face 322 achieve similar or same function, thus are interchangeable, on the basis that the second light L2 is refract^¬ ed and emerges through any of the first surface 321 or the second surface 322 before being reflected by the other one.

The above is merely preferred embodiments of the present in^¬ vention but not to limit the present invention. For the per^¬ son skilled in the art, the present invention may have vari^¬ ous alterations and changes. Any alterations, equivalent sub- stitutions, improvements, within the spirit and principle of the present invention, should be covered in the protection scope of the present invention.

List of reference signs

1 light source

2 bottom surface

3 protruding surface 4 recessed region

5 incident surface

31 first sub region

32 second sub region

33 third sub region

321 first surface

322 second surface

331 third surface

332 fourth surface

LI first light

L2 second light

L3 third light

LI' first emergent light

L2' second emergent light

L3' third emergent light

Claims

Patent claims

A lens (100) for a light source (1), the lens (100) com^¬ prising a bottom surface (2) and a protruding surface

(3) bulging from the bottom surface (2), the bottom surface (2) comprising a recessed region (4), and a surface of the recessed region (4) being configured as an inci^¬ dent surface (5) , characterized in that the protruding surface (3) comprises: a first sub region (31), by which first light (LI) from the light source (1) is refracted to emerge and form first emergent light (LI'); a second sub region (32), by which second light (L2) from the light source (1) is reflected and refracted to form se^¬ cond emergent light (L2'); and a third sub region (33), by which third light (L3) from the light source (1) is reflected and refracted to form third emergent light

(L3' ) .

The lens (100) according to Claim 1, characterized in that the first emergent light (LI'), the second emergent light (L2') and the third emergent light (L3' ) form om- ni-directional illumination.

The lens (100) according to Claim 2, characterized in that the first emergent light (LI') mainly provides side illumination, the second emergent light (L2') mainly provides backward illumination and the third emergent light (L3' ) mainly provides forward illumination.

The lens (100) according to Claim 1 or 2, characterized in that the first sub region (31), the second sub region (32) and the third sub region (33) are arranged in se^¬ quence from the bottom surface (2) in a bulging direc^¬ tion.

5. The lens (100) according to Claim 1 or 2, characterized in that the second sub region (32) comprises first sur^¬ faces (321) and second surfaces (322) arranged alter^¬ nately in groups, wherein a part of the second light (L2), after being reflected by the first surfaces (321), emerges through the second surfaces (322) to form a part of the second emergent light (L2') .

6. The lens (100) according to Claim 5, characterized in that a part of the second light (L2), after being re^¬ flected by the second surfaces (322), emerges through the first surfaces (321) to form another part of the se^¬ cond emergent light (L2') .

7. The lens (100) according to Claim 5, characterized in that the first surface (321) and the second surface (322) of each group form a predetermined angle.

8. The lens (100) according to Claim 1 or 2, characterized in that the third sub region (33) comprises a third sur^¬ face (331) and a fourth surface (332), wherein a part of the third light (L3) , after being reflected by the third surface (331), emerges through the fourth surface (332) to form a part of the third emergent light (L3' ) .

9. The lens (100) according to Claim 8, characterized in that a part of the third light (L3) , after being re^¬ flected by the fourth surface (332), emerges through the third surface (331) to form another part of the third emergent light (L3' ) .

10. The lens (100) according to Claim 9, characterized in that the fourth surface (332) is configured in such a manner that the third light (L3) , after reflected by the fourth surface (332), forms another part of the converged third emergent light (L3' ) .

11. The lens (100) according to any one of Claims 1-5, char^¬ acterized in that, viewed in a cross section perpendicu^¬ lar to the bottom surface (2) and passing through the optical axis (X) of the lens (100), the first sub region (31) is configured to gradually get close to the optical axis (X) from the bottom surface (2) in the bulging di^¬ rection .

12. The lens (100) according to Claim 11, characterized in that the first sub region (31) has a spline profile in the cross section.

13. The lens (100) according to any one of Claims 1-5, char^¬ acterized in that, viewed in a cross section perpendicu^¬ lar to the bottom surface (2) and passing through an optical axis (X) of the lens (100), the first surface

(321) is configured to gradually go away from the opti^¬ cal axis (X) along a bulging direction, and the second surface (322) is configured to gradually get close to the optical axis (X) along the bulging direction.

14. The lens (100) according to Claim 13, characterized in that the first surfaces (321) and the second surfaces

(322) have a spline profile in the cross section.

15. The lens (100) according to any one of Claims 1-5, char^¬ acterized in that, viewed in a cross section perpendicu^¬ lar to the bottom surface (2) and passing through an optical axis (X) of the lens (100), the third surface (331) is configured to gradually get close the optical axis (X) in the bulging direction, and the fourth sur- face (332) is configured to gradually go away from the optical axis (X) in the bulging direction.

16. The lens (100) according to Claim 15, characterized in that the third surface (331) and the fourth surface (332) have a spline profile in the cross section.

17. The lens (100) according to any one of Claims 1-5, char^¬ acterized in that the lens (100) is configured rotation- ally symmetrie.

18. The lens (100) according to any one of Claims 1-5, char^¬ acterized in that the recessed region (4) is configured with a hemispherical profile.

19. The lens (100) according to any one of Claims 1-5, char^¬ acterized in that the lens (100) is made of a transpar^¬ ent optical plastic or glass.