Insert for a light emitting device

Abstract

The present invention relates to a light emitting device (1) comprising a substrate (2) comprising a plurality of individually controllable light sources (3) adapted for, in operation, emitting light, and at least one insert (4) comprising at least partially light-blocking material and having a longitudinal extension being parallel to the substrate (2). The insert (4) comprises a plurality of transverse elements (5) having a proximal end (5) arranged in proximity of the substrate (2) and a distal end (5) arranged at a distance from the proximal end (5). The transverse elements (5) are substantially perpendicular to the substrate (2), the plurality of transverse elements (5) dividing the substrate into at least a first segment (6) comprising a first group of the light sources (3), a second segment (6) comprising a second group of the light sources (3), and a third segment (6) comprising a third group of light sources (3).

Claims

1. A light emitting device comprising: a substrate comprising a plurality of individually controllable light sources adapted for, in operation, emitting light, at least one insert comprising a partially light-blocking material and having a longitudinal extension being parallel to said substrate, said insert comprising a plurality of transverse elements having a proximal end arranged in proximity of said substrate and a distal end arranged at a distance from said proximal end, said transverse elements being substantially perpendicular to said substrate, said plurality of transverse elements dividing said substrate into at least a first segment comprising a first group of said light sources, a second segment comprising a second group of said light sources, and a third segment comprising a third group of light sources, wherein the proximal end of at least one transverse element does not intersect any light source of said plurality of light sources, wherein the at least one transverse element gradually transforms/changes in shape over its height to a different profile at the distal end, and wherein viewed in projection on a plane along the height of the transverse elements, the at least one transverse element is non-straight, and the proximal end has a stepped profile and the distal end is smoothly curved and wherein the at least one transverse element gradually transforms/changes in shape over its height from the stepped profile to the smooth profile.

2. The light emitting device according to claim 1, wherein the distal end of said at least one transverse element has a thickness below 0.2 mm.

3. The light emitting device according to claim 1, wherein said transverse elements are intersecting.

4. The light emitting device according to claim 1, wherein said insert comprises a frame and wherein said transverse elements are arranged within said frame.

5. The light emitting device according to claim 1, wherein at least one transverse element in said plurality of transverse elements comprises a reflective coating.

6. The light emitting device according to claim 1, wherein said plurality of light sources are arranged in parallel rows across said substrate.

7. The light emitting device according to claim 1, wherein said light emitting device further comprises a light exit window being arranged substantially parallelly to said substrate such that said distal end of said at least one transverse element is arranged in proximity of or in contact with said light exit window.

8. The light emitting device according to claim 7, wherein said light exit window is a diffuse transmissive sheet.

9. The light emitting device according to claim 7, wherein said light exit window is a light collimating plate.

10. The light emitting device according to claim 7, wherein at least said distal end of said transverse element is white.

11. The light emitting device according to claim 1, wherein said insert is manufactured by a fused deposition modeling (FDM).

12. A luminaire comprising a light emitting device according to claim 1 and a fixation element configured to support the light emitting device.

13. The luminaire according to claim 12, wherein said luminaire is configured for a suspended configuration.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) This and other aspects of the present invention will now be described in more detail, with reference to the appended drawings showing embodiments of the invention.

(2) FIG. 1 shows a perspective view of a light emitting device comprising insert according to the present invention;

(3) FIG. 2 shows a cross-sectional view of a light emitting device according to the invention;

(4) FIGS. 3A-3C show different patterns obtainable in the light emitting device according to the present invention;

(5) FIGS. 4A and 4B illustrate the embodiment of the insert of the present invention providing improved pattern edges;

(6) FIG. 5A-6B show different embodiments of the insert similar to the one shown in FIGS. 4A-4B.

(7) As illustrated in the figures, the sizes of layers and regions are exaggerated for illustrative purposes and, thus, are provided to illustrate the general structures of embodiments of the present invention. Like reference numerals refer to like elements throughout.

DETAILED DESCRIPTION

(8) The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which currently preferred embodiments of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided for thoroughness and completeness, and fully convey the scope of the invention to the skilled person.

(9) FIG. 1 illustrates a light emitting device 1 comprising a substrate 2 comprising a plurality of individually controllable light sources 3 adapted for, in operation, emitting light. The plurality of light sources 3 is arranged in rows.

(10) The light emitting device 1 further comprises an insert 4 comprising at least partially light-blocking material, e.g. semi-transparent material.

(11) The insert 4 has a longitudinal extension R being parallel to the substrate 2. The longitudinal extension R of the insert is the same as the longitudinal extension of the substrate 2. The insert 4 comprises a plurality of transverse elements 5 having a proximal end 5 arranged in proximity of the substrate 2 and a distal end 5 arranged at a distance from the proximal end 5. The distance between the proximal end 5 and the distal end 5 may be from 1 cm to 20 cm. The transverse elements 5 are arranged substantially perpendicularly to the substrate 2. It is further conceivable that the transverse elements 5 are arranged at different angles relative to the substrate 2. Such an embodiment offers the advantage of enhanced optical performance of the light emitting device 1.

(12) Each transverse element of the plurality of transverse elements has a length Ld in the longitudinal direction essentially parallel to the plane of the substrate, a thickness T, and a height H from the proximal end to the distal end. The thickness T and the height H are measured perpendicular to the light direction. The height H of the transverse elements is measured substantially perpendicularly to the plane of the substrate, e.g. 9010 to the substrate. The length, height and/or thickness of each transverse element may be same as or different from the length, height and/or thickness of the other transverse elements.

(13) The plurality of transverse elements 5 divides the substrate 2 into at least a first segment 6 comprising a first group of the light sources 3, a second segment 6 comprising a second group of the light sources 3, and a third segment 6 comprising a third group of light sources 3. The different groups of light sources 3, 3 and 3 may be operated individually such that desired pattern is created. The number of segments may be at least five, at least ten or at least fifteen. Increased number of segments provides for an increased number of available patterns. The different patterns that may be provided by the insert are depicted in FIGS. 3A-3C.

(14) The plurality of transverse elements 5 are arranged in a combination of straight configuration and curved configuration. In particular, the insert 4 comprises eight curved transversed elements and four straight elements. The transverse elements 5 are intersecting.

(15) The light emitting device 1 comprises a light exit window 8 being arranged substantially parallelly to the substrate 2 such that the distal end 5 of the at least one transverse element 5 is arranged in contact with the light exit window 8.

(16) The light exit window 8 may be a diffuse transmissive sheet. Alternatively, or additionally, the light exit window 8 may be a light collimating plate.

(17) The insert 4 may comprise a frame 7, and the transverse elements 5 may be arranged within the frame 7. In the shown figures the frame 7 is square, but as said it may have any suitable shape.

(18) As may be seen in FIG. 2, the light sources 3, 3 and 3 are individually controllable. Thus, in the embodiment shown in FIG. 2, the first group of light sources 3 in the first segment 6 is switched off, while the second and the third groups of the light sources 3 and 3 are switched on.

(19) FIG. 4a depicts a light emitting device 101 comprising a substrate 102. As mentioned above, depending on the configuration of the light sources 103 and the transverse elements 105 of the insert 104, at least one light source may become covered by a transverse element, which impairs the contrast between the segments of the light emitting device resulting in a poor optical pattern. In order to avoid this undesired effect, the proximal end 105 of at least one transverse element 105 may be non-straight, as shown in FIG. 4A and 4B. In such an embodiment, the proximal end 105 of the at least one transverse element 105 would not intersect any light source of the plurality of light sources 103. The term non-straight in the context of the present invention may mean a stepped or a zig-zac configuration.

(20) As mentioned above, the distal end 105, 205 and 305 of each transverse element 105, 205, 305 may be straight or smoothly curved. The proximal end 105, 205, 305 of each transverse element 105, 205, 305 may be straight, stepped straight or stepped curved. As mentioned above, stepped straight or stepped curved configuration offers the advantage of avoiding intersection of the transverse elements with the light generating/emitting part of any light source 106 of the plurality of light sources, as illustrated in FIG. 4a. As may be seen in FIGS. 4a, 5a and 6a, when the proximal end has a stepped profile and the distal end is smoothly curved, viewed in projection on a plane along the height of the transverse elements, the transverse element gradually transforms/changes in shape over its height from the stepped profile to the smooth profile.

(21) FIG. 5A depicts an embodiment of a light emitting device 201 comprising a substrate 202 and an insert 204 wherein the proximal end 205 of the insert 205 has a pleated configuration, thus providing a sharp contract as may be seen in FIG. 5B. Such an insert may be used if the light emitting device comprises many small light sources. Another embodiment is shown in FIG. 6A, wherein the proximal end 305 of the insert 305 has only two non-straight portions. As may be seen in FIG. 6B, even in this case the contrast between the illuminated and the non-illuminated segments is good.

(22) The person skilled in the art realizes that the present invention by no means is limited to the preferred embodiments described above. On the contrary, many modifications and variations are possible within the scope of the appended claims. For example, if the emitted light is highly directional it would not need a beam shaping element to fulfill the requirement of this invention.

(23) Additionally, variations to the disclosed embodiments can be understood and effected by the skilled person in practicing the claimed invention, from a study of the drawings, the disclosure, and the appended claims. In the claims, the word comprising does not exclude other elements or steps, and the indefinite article a or an does not exclude a plurality. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.