Abstract: A gas-measuring arrangement (1) with an open optical measuring section (7) is formed by a measuring device (5) with an array of lenses (10, 12, 19, 24), a phase mask (22), an optical path mirror (16) positioned obliquely, and a reflecting mirror (3) located outside the measuring device (5) at the end of the open measuring section (7). The light is decoupled to a detector (26) via a phase mask (22) and the optical path mirror (16). The phase mask (22) diverges a light intensity spot and the light intensity ring is decoupled by an obliquely positioned optical path mirror (16) towards a detector (26).

Abstract: A projector for multicolor images includes light sources, which emit light of different wavelengths. The projector uses additive mixing of colors of the light from said three light sources and the maximum luminous flux at the white point is limited by the maximum luminous flux of the first light source. the projector make a white balance adjustment by adjusting the intensity and/or on-state times of the light sources.

Abstract: A projection device for projecting a multi-colored image including a light source unit emitting light of different colors, a light modulator unit, illumination optics arranged between the light source unit and the light modulator unit and directing light from the light source unit onto the light modulator unit, projection optics arranged following the light modulator unit. The projection optics project an image generated by means of the light modulator unit onto a projection surface and the light source unit includes light emitting diodes as the light-generating elements.

Abstract: A device for homogeneous, multi-color illumination of a surface includes first and second light sources emitting light of different colors, a combining unit directing the light from the light sources into a common beam path, and including a condenser system having one first lens array each between the combining unit and each light source and an optical unit having positive refractive power in the common beam path.