Abstract: A light emitting diode (LED) lighting system for producing white light is disclosed. The system comprises sets of LEDs arranged to emit light with different wavelength ranges and associated with different sets of characteristics, and a driving circuit arranged to drive the LEDs. The driving circuit comprises an input for desired light intensity, color rendering index, and color temperature, an input for signals for LED temperature, a model for determining driving currents for said sets of LEDs from said parameters, signals, and characteristics for each of said sets of LEDs; and a current driver for the LEDs. At least one of the sets of LEDs comprises a first subset of LEDs with a first wavelength sub-range and a first set of characteristics, and a second subset of LEDs with a second wavelength sub-range and a second set of characteristics.

Abstract: The invention provides a light module (1) arranged to produce a beam of light (25) with a scattering pattern that is electrically variable. The module comprises a light source (2) arranged to provide a beam of light (5); and an electrically adjustable optical element (300) arranged to adjust the beam of light (5) from light source (2). The adjustable optical element comprises a first cell (10) with a first liquid crystal gel (11); optionally a polarization rotator (30); a second cell (20) with a second liquid crystal gel (21); and a unit 40 for applying a voltage across at least one of the first and second cells (10,20). Especially, the light module (1) provides a beam of light (25) with an anisotropic light distribution.

Abstract: A translucent wall element comprising a first plate-like member (1) of a transparent material and a second plate-like member (2) of a translucent material positioned at the outer side of said first plate-like member (1) substantially parallel to said first plate-like member. Means for coupling light into said first plate-like member are present. The surface (7) of said first plate-like member (1) is provided with spots of light-distribution means (8) at the side facing the second plate-like member (2). The light-distribution means (8) direct light radiation towards the other side of said first plate-like member (1).

Abstract: A variable reflector device, comprising a reflector (6) arranged to direct light from a light source (7) and a casing (5) containing the reflector (6), a portion of said casing (5) being transparent to light directed by the reflector (6). The reflector (6) is formed by a meniscus (2) at an interface between two immiscible fluids (3,4) contained in said casing (5). According to this design, the spatial distribution of light from the light source is changeable by changing the shape of the meniscus between the two fluids. Since a change in shape of the meniscus is effected by a displacement of fluids rather than of mechanical parts, the change in reflector shape can generally be performed faster and with less energy consumption than is the case with previously known designs. Further, a meniscus between two immiscible fluids can, due to the nature of fluids, take on several different shapes, which is not the case when a solid body reflector is utilised.

Abstract: A light-guiding system comprising a plate-like light-emitting element (20) provided with means for emitting light through at least part of its front surface (22). Light is coupled in by a plate-like light-guiding member (21) connected to a lateral side of said lightemitting element (20). One or more interstices (25) are present between said light-emitting element (20) and said light-guiding member (21).

Abstract: A light-guiding system comprising a plate-like light-guiding member (1) provided with a lateral surface for coupling in light into said light-guiding member (1). The ends of a number of light transmission rods (6) are connected to said lateral surface, while said light-guiding member (1) and said light transmission rods (6) are one piece of the same material.

Abstract: The invention relates to a road illumination system for forming a low beam in traffic applications comprising a light source and a reflecting surface formed by a multiplicity of reflector segments arranged around a central optical axis. According to the invention, the light source emits light over an angle of at most 180° in a direction facing away from the intersection of the central optical axis and the reflecting surface and the reflector segments are parabolically-shaped and have a segment optical axis parallel to the central optical axis, while the reflector segments are positioned such that the segment optical axis substantially intersects with an edge of the light source. Preferably, the illumination system is provided on poles (5, 5?, . . . ) or on a crash barrier adjacent the traffic lanes 1. Alternatively, the illumination system is a vehicle headlamp. Preferably, the light source (13) is a (white) lightemitting diode.

Abstract: A luminaire for projecting an image comprises a housing (1) having a light emission window (2). The housing (1) accommodates a light source (3), an optical system (4) for directing light originating from the light source (3) along a longitudinal axis (5), and an image-forming surface (6) which is positioned orthogonally with respect to the longitudinal axis (5). According to the invention, the light source is a LED (3), and the optical system (4) comprises a collimating element (14) for collimating the light originating from the LED (3). Preferably, the luminaire comprises only one LED (3) which, during operation, has a luminous flux of at least 5 lm. Preferably, the housing (1) also comprises a focusing lens (15) for focusing the collimated light originating from the collimating element (14) on the image-forming surface (6) and, preferably, a projection lens (7, 7′) for projecting an image of the image-forming surface (6). Preferably, parts of the collimating element show total internal reflection.

Abstract: A luminaire for projecting an image comprises a housing (1) having a light emission window (2). The housing (1) accommodates a light source (3), an optical system (4) for directing light originating from the light source (3) along a longitudinal axis (5), and an image-forming surface (6) which is positioned orthogonally with respect to the longitudinal axis (5). According to the invention, the light source is a LED (3), and the optical system (4) comprises a collimating element (14) for collimating the light originating from the LED (3). Preferably, the luminaire comprises only one LED (3) which, during operation, has a luminous flux of at least 5 lm. Preferably, the housing (1) also comprises a focusing lens (15) for focusing the collimated light originating from the collimating element (14) on the image-forming surface (6) and, preferably, a projection lens (7, 7′) for projecting an image of the image-forming surface (6). Preferably, parts of the collimating element show total internal reflection.