Abstract: An LED module includes a carrier and a number of light sources. Each light source is arranged on the carrier in such a way that the LED module comprises a radiation uniformity which is less than the statistical mean of a radiation uniformity distribution, wherein the radiation uniformity distribution is based on a plurality of LED modules with a random arrangement of the light sources.

Abstract: Described is an optical waveguide having a main direction of extension, at least one radiation entrance face, and a radiation exit face that extends longitudinally to the main direction of extension, wherein at least one radiation entrance face extends transversely to the main direction of extension, and the at least one radiation entrance face has two convexly curved subregions that are connected to each other by a kink-like or concavely shaped indentation. An optical device formed with such a waveguide is also described, as is a display device.

Abstract: A projection apparatus is specified, comprising a light modulator having a light receiving region with a cross-sectional area to be illuminated of the size AM and a maximum acceptance angle ? for incident light, and at least one light source by means of which, during its operation, a light cone is produced for illuminating said cross-sectional area of said light receiving region and which comprises a number N of LED chips having a maximum radiation angle ?. At least one of the LED chips has a radiation decoupling area of the size AD. The relation 0.7·(AM·sin2(?))/(AD·sin2(?)·n2)?N?1.3·(AM·sin2(?))/(AD·sin2(?)·n2) applies, where n is equal to 1 or to the refractive index of a coupling medium with which the LED chips are provided.

Abstract: This invention relates to uniform backlighting of surfaces by semiconductor light sources. Various semiconductor light sources are combined into identical illumination groups. These identical illumination groups are arranged so that uniform backlighting of a surface is made possible. For homogeneous color mixing to be achieved, especially at edges, each illumination group in the arrangement has at least one adjacent illumination group in a different orientation.

Abstract: An LED module includes a carrier and a number of light sources. Each light source is arranged on the carrier in such a way that the LED module comprises a radiation uniformity which is less than the statistical mean of a radiation uniformity distribution, wherein the radiation uniformity distribution is based on a plurality of LED modules with a random arrangement of the light sources.

Abstract: A subassembly for a document validator. In an implementation, the subassembly includes a housing, a light pipe core seated in the housing, a light control layer and at least one light source. The apparatus may also include a prism structure layer between a top diffusing surface and the light control structure. The housing may also include at least one input light port on at least one end of the light pipe core.

Abstract: A subassembly for a document validator. In an implementation, the subassembly includes a housing, a light pipe core seated in the housing, a light control layer and at least one light source. The apparatus may also include a prism structure layer between a top diffusing surface and the light control structure. The housing may also include at least one input light port on at least one end of the light pipe core.