Abstract: In one embodiment, a color, transmissive LCD uses red, green, and blue LEDs as the light source. The red LED is optically coupled to a first edge of a rectangular light guide; the green LED is optically coupled to a second edge of the light guide; and the blue LED is optically coupled to a third edge of the light guide. Three sets of deformities in the light guide selectively direct the R, G, and B light out of the front surface of the light guide. The R, G, and B LEDs are constantly on and there is no color filtering. In another embodiment, a blue light LED is optically coupled to one or more edges of a light guide, and phosphor strips are placed on a surface of the light guide coinciding with the red and green pixel columns. Deformities below the red and green phosphor strips and below the blue pixel areas direct blue light to the backs of the phosphor strips and to the blue pixel areas. If an ultraviolet light LED is used, phosphor strips for the blue pixel areas would also be used.

Abstract: A backlight system for illuminating a display device comprises a light-emitting panel (1) having a front wall, an opposing rear wall and edge areas (4). At least one of the edge areas (4) is light-transmitting and associated with a light source. The light source associated with the light-transmitting edge areas (4) of the light-emitting panel (1) comprises symmetric clusters (C) of light-emitting diodes having three mutually different light emission wavelengths, for example symmetric clusters (C) of blue, green and red LEDs (6G, 6B, 6R, 6B′, 6G′; 6G, 6B, 6R, 6B′, 6G′; . . . ) FIG. 2A.

Abstract: A backlight system comprises at least two light-emitting panels (1; 11) having a front wall (2; 12), an opposing rear wall (3; 13) and opposite edge surfaces (4, 14; 5, 15). At least one of the edge surfaces (4; 14) is light-transmitting and associated with a light source (6; 16). Light originating from the light source (6; 16) is diffused in the light-emitting panels (1; 11) and coupled out of the light-emitting panels (1; 11) in the direction of a display device (25), preferably a LCD device. The light source (6) associated with the light-emitting panel bearing reference numeral 1 comprises clusters of red and blue or red and green LEDs. The light source (16) associated with the light-emitting panel bearing reference numeral 11 comprises clusters of blue and green LEDs or only green LEDs.

Abstract: A lens array for a lamp directs light to a light conduit such as an optical fiber or light pipe for guiding light to a remote location. An array of LED serve as light sources. The lens array includes an integrally formed member having a number of collimator lenses positioned in the lens array so that each lens can operate as a collimator for a corresponding LED to produce a respective collimated beam of light. The lenses have optical properties that are optimized according to where their corresponding LED are positioned in the LED array, so that the lens array is provided with lens prescriptions that produce refraction of the collimated beams of light toward an entrance aperture of the light conduit.

Abstract: A headlamp (2; 3) of a vehicle (1) has a light source (4; 5) comprising a plurality of opto-electronic elements (11; 12; 13; 14), preferably light-emitting diodes (LEDs). At least one of these opto-electronic elements (11; 12; 13; 14) has, in operation, a luminous flux of 5 lm or higher. According to the invention, the spatial distribution of the light beam (6, 6′, . . . ; 7, 7′, . . . ) generated by the light source (4; 5) is continuously adjustable. Preferably, the light source (4; 5) comprises opto-electronic elements (11; 12; 13; 14) only. Preferably, the spatial distribution is influenced by the speed of the vehicle (1), the rotational position of the steering wheel of the vehicle (1), the weather conditions, and it can also be influenced by the driver of the vehicle (1). Preferably, the spectral characteristics of the light beam (6, 6′, . . . ; 7, 7′, . . . ) generated by the light source (4; 5) depend on the position in the light beam (6, 6′, . . . ; 7, 7′, . . . ).

Abstract: A color, transmissive LCD is described herein which uses red, green, and blue LEDs as the light source. The R, G, and B LEDs are coupled to separate light guides, one light guide for each color. These light guides may take the form of three overlying plastic or glass sheets. In another embodiment, thin fiber optic cables arranged parallel to each other on a supporting surface are used as the light guides, and each fiber optic cable is optically coupled to only one R, G, or B LED in a repeating pattern. The light guides contain deformities to emit light coinciding with the positions of the red, green, and blue pixels. The R, G, and B LEDs are constantly on, and there is no color filtering.

Abstract: The system comprises a display device having a pattern of pixels associated with color filters (5B, 5G, 5R) and a backlight system for illuminating the display device, which backlight system comprises a light-emitting panel (11) and a light source (16) associated with the light-emitting panel (11). The light source (16) comprises a plurality of light-emitting diodes (LEDs) of at least three different colors, the LEDs being associated with the color filters (5B, 5G, 5R). Preferably, the spectral emission of each of the LEDs substantially matches the transmission spectrum of the color filters (5B, 5G, 5R). Preferably, the bandwidth (FWHM=full width at half maximum) of the LEDs ranges from 10≦FWHM≦50 nm. Preferably, the intensity of the light emitted by the LEDs varies with the light level of the image to be displayed by the display device. Preferably, the intensity of the light emitted by the backlight system is controllable on a frame-to-frame basis and, preferably, for each color.

Abstract: A backlight system for illuminating a display device (3) comprises a light-emitting panel (1) having a light-emission window (2) and at least one edge surface (4) for coupling light into the light-emitting panel (1). The backlight system further comprises a light mixing chamber (5) provided with a light source (6). The light mixing chamber (5) is associated with the edge surface (4). According to the invention, the light source (6) comprises a plurality of clusters of light-emitting diodes (LEDs) having different light-emission wavelengths, the clusters being arranged at a pitch P with respect to each other. The ratio of the height H of the light mixing chamber (6) to the pitch P of the clusters meets the relation 0.1≦H/P≦10, preferably 0.2≦H/P≦2. Preferably, each cluster comprises one blue, one green and one red LED, or one blue, two green and one red LEDs. Preferably, each LED has a luminous flux of at least 5 lumen.

Abstract: A backlight system comprises at least two light-emitting panels (1; 11) having a front wall (2; 12), an opposing rear wall (3; 13) and opposite edge surfaces (4, 14; 5, 15). At least one of the edge surfaces (4; 14) is light-transmitting and associated with a plurality of light sources (6, 16). Light originating from the light sources (6; 16) is diffused in the panel (1; 11). Sub-surfaces (8, 18) of the rear walls (3, 13) are provided with means for extracting light from the panel (1, 11). In operation, said sub-surfaces (8, 18) project light on areas (9, 19) of an (imaginary) plane (40) which is positioned parallel to the light-emitting panels (1, 11). Said projected areas (9, 19) in the plane (40) are substantially contiguous. Preferably, said sub-surfaces (8, 18) are remote from the light-transmitting edge surfaces (4; 14). Preferably, each of said sub-surfaces (8, 18) forms a single surface covering half the front wall (2, 12) of the light-emitting panel (1, 11).

Abstract: The system comprises a display device with a pattern of pixels (3) controlled by a control circuit (8) and a backlight system for illuminating the display device, which backlight system comprises a light-emitting panel and a light source (16, 16′, 16″, . . . ) associated with the light-emitting panel. The light source comprises a plurality of light-emitting diodes (LEDs) of at least two different colors. The control circuit (8) also controls the luminous flux of the LEDs. Preferably, the intensity of the light emitted by the LEDs (16, 16′, 16″) varies with the light level of the image to be displayed by the display device. Preferably, the intensity of the light emitted by the backlight system can be controlled on a frame-to-frame basis and, preferably, also for each color. Preferably, the LEDs comprise a plurality of red, green, blue (and amber) LEDs, each, preferably, having a luminous flux of at least 5 lumen.

Abstract: A lighting system includes at least two light-emitting diodes each emitting, in operation, visible light in a preselected wavelength range. A converter converts part of the visible light emitted by one of the diodes into visible light in a further wavelength range so as to optimize the color rendition of the lighting system. The diodes include a blue light-emitting diode and a red light-emitting diode. Further, the converter includes a luminescent material for converting a portion of the light emitted by the blue light-emitting diode into green light.