| 摘要 |
The present invention relates to a light source with diffraction structure, intended particularly for directional illumination of a surface, wherein a diffraction structure (2) is disposed on a planar or curved base, between at least one LED (1) and the surface (3) to be illuminated (3). The invention is characterized in that the diffraction structure (2) situated on the planar base (4) consists of a microstructure composed of dents of asymmetrical section with the interval of 500 nm to 1 mm and a depth in the range of 500 nm to 100 microns, whereby each point (x, x.1...x.n) of the diffraction structure (2) is illuminated by the LED (1) under a corresponding angle ({alpha}, {alpha}1…..{alpha}..n), whereby the light, after passage through the diffraction structure (2) is deflected under the corresponding angle of incidence ({alpha}, {alpha}1…..{alpha}..n) onto the illuminated surface (3) and whereby a spectral characteristic at each point of the illuminated surface (3) is identical with the spectral characteristic of the LED (1). The light source according to the present invention can be for instance used for public illumination, where it is possible to illuminate a predetermined surface and complete it with a textural or image announcement, optionally with a road marking or advertisement. |
