Illumination device
An illumination device may include a hollow body having at least one light emission opening, wherein the hollow body has at least partly a reflective surface at its inner side, and at least one semiconductor luminous element, wherein a predominant portion of the light emitted by the semiconductor luminous element is incident on the inner side of the hollow body and is reflected from there through the light emission opening. The device may furthermore include a covering for the light emission opening with a grid-type arrangement of light transmission openings, wherein the at least one semiconductor luminous element is fixed to the covering and is directed at the inner side of the hollow body, and wherein a side area of the covering that surrounds the light transmission openings is at least partly reflectively coated.
1. An illumination device, comprising: a hollow body having at least one light emission opening, wherein the hollow body has at least partly a reflective surface at its inner side, and at least one semiconductor luminous element, wherein a predominant portion of the light emitted by the semiconductor luminous element is incident on the inner side of the hollow body and is reflected from there through the light emission opening, and furthermore comprising a covering for the light emission opening with a grid-type arrangement of light transmission openings, wherein the at least one semiconductor luminous element is fixed to the covering and is directed at the inner side of the hollow body, and wherein a side area of the covering that surrounds the light transmission openings is at least partly reflectively coated.
2. The illumination device as claimed in claim 1 , wherein the reflective surface has at least one diffusely reflective region.
3. The illumination device as claimed in claim 1 , wherein the covering constitutes a heat sink for the at least one semiconductor luminous element.
4. The illumination device as claimed in claim 1 , wherein the covering is fashioned in the form of a rectangular or hexagonal lattice.
5. The illumination device as claimed in claim 1 , wherein the covering is constructed from modules of identical form.
6. The illumination device as claimed in claim 1 , wherein a ratio of a height of the light emission opening to a grid pitch is in the range of 1 to 2.
7. The illumination device as claimed in claim 1 , wherein the light transmission opening substantially has a form of a parabolic concentrator.
8. The illumination device as claimed in claim 1 , which is configured such that light is emitted from the illumination device substantially at an emission angle of not more than 60°.
9. The illumination device as claimed in claim 1 , wherein the semiconductor luminous element comprises at least one light-emitting diode.
10. The illumination device as claimed in claim 9 , wherein a wavelength-converting phosphor is present on at least one part of the diffusely reflective surface.
11. The illumination device as claimed in claim 1 , wherein the reflective surface is shaped such that it concentrates light emitted by the at least one semiconductor luminous element onto the associated light emission opening.
12. The illumination device as claimed in claim 1 , wherein the hollow body is provided with ventilation holes.
13. The illumination device as claimed in claim 12 , wherein the ventilation holes are provided with respective reflective coverings.
14. The illumination device as claimed in claim 7 , wherein a form of the light transmission opening is give by the equations
x= 2 ·r ·(((1+sin α)·(sin(β−α))/(1−cos β))−1)
and
y= 2 ·r ·((1+sin α)·cos(β−α))/(1−cos β).
15. The illumination device as claimed in claim 14 , wherein: 1−α>30° holds true.
16. The illumination device as claimed in claim 12 , wherein the hollow body is provided with ventilation holes in a rear wall lying opposite the light emission opening.