Abstract: The present invention relates to a method and a system of reducing motion blur in a liquid crystal cell. A basic idea of the invention is to process, in an LCD system, a luminance component (Y) of a picture frame to provide motion blur reduction, wherein overdrive is applied to the luminance component only. First, a luminance component related to a first picture frame is stored. Thereafter, a luminance component of a subsequent picture frame is acquired. To reduce motion blur in the LCD, a modified luminance component (Y?) is created based on a difference between the value of the luminance component of the subsequent frame and the value of the luminance component related to the first frame. Hence, based on the value of the difference in the luminance components, and color components (U, V) of the subsequent picture frame, a drive voltage is applied to the LC cell.

Abstract: In an active matrix electroluminescent display device, comprising an array of display pixels, each pixel comprises an electroluminescent display element, active matrix circuitry including at least one drive transistor for driving a current through the display element, means for determining an overall brightness level of an image to be displayed in a frame period, means for controlling the at least one drive transistor of each pixel in dependence on, (1) a respective input signal providing a drive level for the pixel, and (2) the overall brightness level. The novel arrangement is capable of controlling the pixels to limit the maximum currents drawn by the pixels, thereby limiting cross-talk effects resulting from voltage drops along row or column conductors. If an image is bright, the pixel drive levels across the image, or at least part of the image, can be reduced, so that the maximum brightness is reduced.

Abstract: The invention provides an illumination system comprising a light-emitting device which excites a first luminescent element, which forms part of the light-emitting device. The light emitted from the first luminescent element and/or the light emitted by the light-emitting device excite a second luminescent element, physically separated from the light-emitting device. By employing two luminescent elements, the first element in the light-emitting device, and the second element physically separated from the light-emitting device, such as on a cover plate, the conversion of light produced by the light-emitting device is performed at both a “local” and a “remote” location, respectively, and the amount of luminescent material required at the remote location may be reduced compared to the situation of the prior art where the light conversion was only performed at a remote location.

Abstract: A driving circuit (10) for driving a plurality of light sources (1) arranged in a series configuration (2) is described. A controllable current source (20) is connected to said series arrangement of light sources. Each light source (1(i)) is bridged by a corresponding controllable switch (25(i)). A controller (30) controls the operation of the current source (20) to set a current level and controls the operative states of the respective switches (25(i)) in order to individually control the light output of the corresponding light sources. The controller (30) is capable of individually setting the switch control signals (SL(O) for the respective switches (25(i)). Especially, the controller (30) is capable of boosting the light output of one selected light source (1(x)) while maintaining the light output of other light sources in the series arrangement (2). To this end, the current level is increased while the other light sources are dimmed.

Abstract: The invention provides an illumination system comprising a light-emitting device which excites a first luminescent element, which forms part of the light-emitting device. The light emitted from the first luminescent element and/or the light emitted by the light-emitting device excite a second luminescent element, physically separated from the light-emitting device. By employing two luminescent elements, the first element in the light-emitting device, and the second element physically separated from the light-emitting device, such as on a cover plate, the conversion of light produced by the light-emitting device is performed at both a “local” and a “remote” location, respectively, and the amount of luminescent material required at the remote location may be reduced compared to the situation of the prior art where the light conversion was only performed at a remote location.

Abstract: The invention provides an illumination system comprising a light-emitting device which excites a first luminescent element, which forms part of the light-emitting device. The light emitted from the first luminescent element and/or the light emitted by the light-emitting device excite a second luminescent element, physically separated from the light-emitting device. By employing two luminescent elements, the first element in the light-emitting device, and the second element physically separated from the light-emitting device, such as on a cover plate, the conversion of light produced by the light-emitting device is performed at both a “local” and a “remote” location, respectively, and the amount of luminescent material required at the remote location may be reduced compared to the situation of the prior art where the light conversion was only performed at a remote location.

Abstract: Disclosed is a driver that includes a main power supply that has outputs coupled across a string of light emitting diodes to supply a main current. A secondary power supply is coupled to a junction between successive light emitting diodes in the string to supply or withdraw a delta current from the junction. The delta current is at least five times smaller than the main current. A controller controls the secondary power supply to generate the delta current to obtain a desired spectral composition of the mixed light emitted by the string.

Abstract: The present invention relates to a method for determining drive values for driving a lighting device at a desired brightness and color.

Abstract: In an active matrix electroluminescent display device, an overall brightness level of an image to be displayed in a frame period is determined. A drive transistor of each pixel is controlled in dependence on an input drive signal for the pixel and on the overall brightness level, for example using a signal processor (30) to vary the pixel drive signals. This arrangement can control the pixels to limit the maximum currents drawn by the pixels, thereby limiting the cross talk effects resulting from voltage drops along row or column conductors. If an image is bright, the pixel drive levels across the image (or at least a part of the image) can be reduced, so that the maximum brightness is reduced.

Abstract: In an active matrix electroluminescent display device, an overall brightness level of an image to be displayed in a frame period is determined. A drive transistor of each pixel is controlled in dependence on an input drive signal for the pixel and on the overall brightness level, for example using a signal processor (30) to vary the pixel drive signals. This arrangement can control the pixels to limit the maximum currents drawn by the pixels, thereby limiting the cross talk effects resulting from voltage drops along row or column conductors. If an image is bright, the pixel drive levels across the image (or at least a part of the image) can be reduced, so that the maximum brightness is reduced.

Abstract: A color electroluminescent, EL, display device comprising an array of pixels (11) each comprising sub-pixels (1) of two or more colors (R, G, B). For at least one of the colors (R, G, B), the pixel (11) comprises a first sub-pixel (RL, GL, BL) comprising a first EL material and a second sub-pixel (Rc, Gc, Bc) comprising a second EL material. The first EL material is of higher lifetime than the second EL material; the second EL material has better color points and/or better color rendition properties than the first EL material. In some embodiments a pixel comprises two red sub-pixels (RL, Rc), two green subpixels (GL, Gc) and two blue sub-pixels (BL, Bc), one sub-pixel of each color (RL, GL, BL) comprising relatively high lifetime EL material and the other sub pixel of each color (Rc, Gc, Bc) comprising relatively good color points EL material. In other embodiments a pixel comprises two blue sub-pixels (BL, Bc) but only one red sub-pixel and one green sub-pixel.

Abstract: An active matrix display comprises a select driver (SD) to drive select electrodes (SE), and a data driver (DD) to supply data (D) to data electrodes (DE). Pixels (10) are associated with intersections of the data electrodes (DE) and the select electrodes (SE). The pixels (10) comprise a light emitting element (L) and a pixel driving circuit (PD). The pixel driving circuit (PD) receives a power supply voltage (VB) via a power supply electrode (PE), and data (D) via a data electrode (DE) to control a brightness of the light emitting element (L). A power supply (PS) supplies the power supply voltage (VB). The power supply electrodes (PE) are arranged to supply the power supply voltage (VB) to the pixel driving circuits (PD) of lines of pixels (10) extending in the same direction as the select electrodes (SE) or in the same direction as the data electrodes (DE).

Abstract: A driving circuit (10) for driving a plurality of light sources (1) arranged in a series configuration (2) is described. A controllable current source (20) is connected to said series arrangement of light sources. Each light source (1(i)) is bridged by a corresponding controllable switch (25(i)). A controller (30) controls the operation of the current source (20) to set a current level and controls the operative states of the respective switches (25(i)) in order to individually control the light output of the corresponding light sources. The controller (30) is capable of individually setting the switch control signals (SL(O) for the respective switches (25(i)). Especially, the controller (30) is capable of boosting the light output of one selected light source (1(x)) while maintaining the light output of other light sources in the series arrangement (2). To this end, the current level is increased while the other light sources are dimmed.

Abstract: The reflective display panel (1), arranged to modulate ambient light for displaying an image, has a pixel (2) and a controller (10,11,100). For the panel (1) to be able to display an image having a flexibly adjusted perceived brightness, the controller (10,11,100) is arranged for providing the pixel (2) with a brightness corresponding to image content and depending on a condition of the ambient light for displaying the image.

Abstract: The invention provides an illumination system comprising a light-emitting device which excites a first luminescent element, which forms part of the light-emitting device. The light emitted from the first luminescent element and/or the light emitted by the light-emitting device excite a second luminescent element, physically separated from the light-emitting device. By employing two luminescent elements, the first element in the light-emitting device, and the second element physically separated from the light-emitting device, such as on a cover plate, the conversion of light produced by the light-emitting device is performed at both a “local” and a “remote” location, respectively, and the amount of luminescent material required at the remote location may be reduced compared to the situation of the prior art where the light conversion was only performed at a remote location.

Abstract: The present invention relates to a driver for a string (STi) of series arranged light emitting diodes (D1i, D2i, D3i) of which at least two emit light having different spectra. The driver comprises a main power supply (PAi) which has outputs coupled across the string (STi) to supply a main current (IAi) to the string (STi). A secondary power supply (PBi) is coupled to at least one of junctions (J1i) between successive light emitting diodes (D1i, D2i) in the string (STi) to supply or withdraw a delta current (IBi) from the junction (J1i). The delta current (IBi) is at least a factor 5 smaller than the main current (IAi). A controller (CO) controls the secondary power supply (PBi) to generate the delta current (IBi) to obtain a desired spectral composition of the mixed light emitted by the string (STi).

Abstract: This invention relates to a lighting system for stimulating a user's energy by emitting bluish wake-up light and tuning the bluish light towards a daytime-like white light.

Abstract: The present invention relates to a method for determining drive values for driving a lighting device at a desired brightness and color.

Abstract: A method for displaying images on a display having backlight is disclosed, where the images is updated periodically with a period. The method comprises the steps of: generating a signal with a pulse pattern for each period depending on the contents of an image to be displayed in that period; and activating backlight in accordance with the signal. Further, a display (100) comprising a display panel (102) and a backlight unit, wherein the backlight unit comprises a controller (104) and a lighting device is disclosed. The controller (104) is arranged to generate a control signal, and the lighting device is arranged to provide backlight to the display panel (102) according to the control signal, wherein the control signal comprises a pulse pattern depending on contents of displayed images.

Abstract: An illuminating member (4) that, independent of any image content, comprises a central region (5) and an enclosing region (6), wherein said enclosing region (6) is adapted to emit light of lower quality than the light emitted by the central region (5). The illuminating member is adapted to illuminate a display panel (2) of a display device. By having the enclosing region emit light of lower brightness (dimming) a significant power reduction can be achieved for a wide range of typical images while largely maintaining the perceived image quality. Further, by using light emitting elements of lower quality for the enclosing region, manufacturing costs may be reduced while largely maintaining the perceived image quality.