Abstract: The illumination system has a plurality of light emitters (R, G, B) and a light collimator (1) for collimating light emitted by the light emitters. Light propagation in the light-collimator is based on total internal reflection (TIR) towards a light-exit window (4) of the light-collimator. At least one light sensor (8) for optical feedback is placed outside the light-collimator and is arranged to receive light emitted by the light emitters exclusively through reflection at the light-exit window of the light-collimator. Preferably, the light sensor is placed substantially coplanar with the light emitters. Preferably, a side wall (35) of the light-collimator is provided with a protruding portion (9) for guiding the light reflected at the light-exit window of the light-collimator towards the light sensor. Preferably, the illumination system is provided with a reflector (12). Preferably, the illumination system comprises a holographic diffuser (17).

Abstract: An illumination system has a plurality of light emitters (R, G, B), at least one light-collimating section (12, 12?, 12?) for collimating the light emitted by the light emitters arranged along a longitudinal axis (25) of the illumination system. The at least one lightcollimating sections merge into a light-mixing section (3) at a side facing away from the light emitters. The light-mixing section has a plurality of side-faces parallel to the longitudinal axis. A surface of the light-mixing section facing away from the light emitters is provided with a light-shaping diffuser (17). Preferably, the light-shaping diffuser is a holographic diffuser. Preferably, the illumination system comprises a plurality of light-collimating sections each of the light-collimating sections being associated with at least one light emitter. The illumination system provides improved spatial and spatio-angular mixing of the light emitted by the light emitters.

Abstract: The illumination system has a light source (1) with a plurality of light emitters (R, G, B). The light emitters comprise at least a first light-emitting diode of a first primary color and at least a second light-emitting diode of a second primary color, the first and the second primary colors being distinct from each other. The illumination system has a facetted light-collimator (2) for collimating light emitted by the light emitters. The facetted light-collimator is arranged along a longitudinal axis (25) of the illumination system. Light propagation in the facetted light-collimator is based on total internal reflection or on reflection at a reflective coating provided on the facets of the facetted light-collimator. The facetted light-collimator merges into a facetted light-reflector (3) at a side facing away from the light source. The illumination system further comprises a light-shaping diffuser (17). The illumination system emits light with a uniform spatial and spatio-angular color distribution.

Abstract: The present invention relates to a system (100) for controlling light output of a lighting system. The system (100) comprises a light mixing circuit (116) comprising a plurality of light sources configured to provide a mixed light output (102) and mounted on a heat-sink (202) together with a temperature sensing means and a controller (108) receiving a set-point (110) from a calibration matrix (104) and generating a driving signal (120, 122) for the light mixing circuit (116). The controller (108) comprises a rescale unit (118) configured to measure power of the driving signal (120, 122) and to rescale the driving signal (120, 122) when the power exceeds a predetermined power threshold, and the controller is configured to receive the heat-sink temperature signal (206) and to calculate a junction temperature from the heat-sink temperature signal, and the controller (108) generates the driving signal (120, 122) as a function of the junction temperature.

Abstract: An illumination system has a plurality (2) of light-collimating sections (12, 12?, 12?) and a light-mixing section (3). The light-collimating sections are arranged substantially parallel to each other along a longitudinal axis (25) of the illumination system. Each of the light-collimating sections is associated with at least one light emitter (R, G, B). Each of the light emitters is being in optical contact with the respective light-collimating section via a dielectric material with a refractive index larger than or equal to 1.3. At a side facing away from the light emitters, the light-collimating sections merge into the light-mixing, the light-collimating sections and the light-mixing section forming one integral part. Light propagation in the light-mixing section is based on total internal reflection and the light-mixing section has a plurality of faces parallel to the longitudinal axis.

Abstract: A color-mixing lighting system has a light-emitting diode (6, 7) emitting first visible light having a first peak wave-length in a first spectral range and has a fluorescent material (8) converting a portion of the first visible light into second visible light having a second peak wavelength in a second spectral range. The second visible light has a full width at half maximum (FWHM) of at least 50 nm. Preferably, the second visible light is red light, the second peak wavelength being in the range from 590 to 630 ran, preferably, in the range from 600 to 615 nm. Preferably, the lighting system comprises a further light-emitting diode (7) for emitting third visible light having a third peak wavelength in a third spectral range. The color-mixing lighting system according to the invention generates white light with a high color-rendering index and allows certain variations in the wavelength of the primaries.

Abstract: An illumination system, preferably for illumination in a car, comprising at least one plain or slightly curved, solid light guide (4) made of transparent material, said light guide receiving light from a light (2) source and being provided with means (5, 6) for extracting light from said light guide, the means for extracting light from said light guide have. Reflecting surfaces (7, 8, 9, 10) the slopes of which are varied as a function of the position of the extracting means in the light guide as well as the position of a reading plane, so as to direct the light flux to a desired reading plane position. Preferably the illumination system a laminated structure of light guide layers, said layers being formed of a light guide layer for diffuse homogeneous illumination (1) and at least one light guide layer (4) for spot illumination of a reading plane.

Abstract: A compact backlight system has a light-emitting panel (1) with a front wall (2), a rear wall (3) situated opposite thereto, and furthermore, between the front and the rear wall (2, 3), a first edge surface (4) and, opposite thereto, a second edge surface (5). A first light source (6) is associated with the first edge surface (4) which is light-transmitting. According to the invention, the light-emitting panel (1) widens over a widening section (100) from the first edge surface (4) in a direction towards the second edge surface (5), and the rear wall (3) is provided over the widening section (100) with a multiplicity of steps (13, 13?, . . . ) of which a surface (17) facing the front wall (2) is substantially parallel to the front wall (2). Preferably, the ratio of the surface area S1 of the first edge surface (4) and the surface area S2 of the second edge surface (5) ranges from 1.5<S2/S1<3.

Abstract: A compact backlight system has a light-emitting panel (1) with a front wall (2), a rear wall (3) situated opposite thereto, and furthermore, between the front and the rear wall (2, 3), a translucent input edge surface (4) for coupling light into the light-emitting panel (1). A light source (6, 6?, . . . ) is associated with the input edge surface (4). According to the invention, the rear wall (3) in a first portion (12) of the light-emitting panel (1) is provided with a multiplicity of steps (13, 13?, . . . ), and a second portion (22) of the light-emitting panel (1) widens from the input edge surface (4) in a direction facing the first portion (12). Preferably, a surface (17) of the steps (13, 13?, . . . ) facing the input edge surface (4) makes an angle ?av?5° (with respect to a normal on a bisecting plane (20) bisecting the light-emitting panel (1).

Abstract: A compact backlighting system for illuminating a display device (12) comprises a light-emitting panel (1) having a front wall (2), an opposing rear wall (3) and edge areas (4). At least one of the edge areas (4) is capable of transmitting light. The backlighting system includes a light source (6) comprising at least one LED, and a light-mixing panel 5 for mixing the light originating from the light source (6). Light originating from the light source (6) is coupled into the light-mixing panel (5) via a light input surface (7), which light is mixed in the light-mixing panel (5) and coupled out via a light output surface (8). The light-mixing panel (5) and the light-emitting panel (1) are arranged so as to extend substantially parallel to each other. Between the light-mixing panel 5 and the light-emitting panel 1, the backlighting system comprises a light transport chamber (9) for transporting the light from the light-mixing panel (5) to the light-emitting panel (1).