Abstract: An embodiment of the present invention provides a method of driving a liquid crystal display device including a liquid crystal panel, and a backlight assembly providing light to the liquid crystal panel by a field sequential driving method, the method includes: displaying an image, at the liquid crystal panel and the backlight assembly, by time-dividing two frames into five sub-frames, wherein when images are displayed in the two frames, images of a first frame and a second frame of the two frames share one blue light.

Abstract: Disclosed is a display device capable of compensating unevenness in brightness caused by physical restrictions of a display device or degradation in image quality caused by a partial reduction in contrast occurring in the local dimming technology using human visual characteristics. A liquid crystal panel ( 101 ) modulates illuminating light in accordance with the transmittance, and displays images on a screen. A backlight ( 102 ) emits the illuminating light to the liquid crystal panel ( 101 ) such that amounts of the illuminating light differ for each light emitting area of the screen. A backlight control unit ( 106 ) controls emission brightness of the backlight ( 102 ) for each light emitting area. A local gradation converting unit ( 104 ) performs gradation conversion on an image signal, and acquires a brightness value for each pixel after the conversion. A backlight driving unit ( 107 ) controls the transmittance for each pixel on the basis of the acquired brightness values after the conversion. The local gradation converting unit sets conversion characteristics for pixels to be processed in the image signal such that the brightness values of the pixels to be processed are low as the lightness of the periphery of the pixels to be processed is high, and performs gradation conversion using the set conversion characteristics.

Abstract: A display device (100) includes a display panel assembly (10) having a plurality of pixels arranged in rows and columns and a backlight unit (40) disposed behind the display panel assembly (10) and having a plurality of pixels arranged in rows and columns. The number of the pixels of the backlight unit (40) is less than a number of the pixels of the display panel assembly (10). The backlight unit (40) includes a plurality of scan electrodes arranged along one of row and column directions and a plurality of data electrodes arranged along the other of the row and column directions; and the pixels of the backlight unit (40) are adapted to emit lights having intensities in accordance with gray levels of the pixels of the display panel assembly.

Abstract: This paper presents an LED backlight driving system for large-scale liquid crystal display panels. High efficiency, high power factor, circuit simplicity, and low cost can be achieved by using a single-stage charge-pump asymmetrical half-bridge converter. To regulate the LED current and brightness for the LED backlight system, some current sharing methods are presented and compared. The requirements for the current sharing and luminance balance among paralleled LED arrays can be satisfied while current ripple is eliminated significantly. Because of the addition of bypass diodes, an alternative current path can be offered when a single LED fails. The LED array will not be extinguished. Reliability of the LED backlight system can thus be improved effectively. A laboratory prototype has been built and tested. The simulation and experimental results are shown to verify the feasibility of the proposed method.

Abstract: This paper presents a LED backlight driving system for large-scale of LCD panels. High efficiency, high power factor, circuit simplicity, and low cost can be achieved by using a single-stage charge-pump asymmetrical-half-bridge converter. To regulate the LED current and brightness for the LED backlight system, some current sharing methods are presented and compared. The requirements for the current sharing and luminance balance among paralleled LED arrays can be satisfied while current ripple is eliminated significantly. Because of the addition of bypass diodes, an alternative current path can be offered when a single LED fails. The LED array will not distinguish. A laboratory prototype has been built and tested. The simulation and experimental results are shown to verify the feasibility of the proposed method.

Abstract: Apparatuses and methods to operate a display device of an electronic device. In some embodiments, a method includes receiving a user setting of a display control parameter, and altering, based on the user setting, an effect of an ambient light sensor value (ALS) on control of the display control parameter. Also, according to embodiments of the inventions, a method of operating a display of an electronic device includes receiving a change to one of a display brightness output level and an ambient light sensor output level, and altering, according to the change, a display contrast output level. In some embodiments, a method of operating a proximity sensor of an electronic device includes receiving a light sensor output, and altering, according to the output, an on/off setting of a proximity sensor. Other apparatuses and methods and data processing systems and machine readable media are also described.

Abstract: It is an object to provide a display device in which a problem of light leakage from a liquid crystal element in black display is reduced or overcome and the contrast is improved It is another object to provide a pixel circuit having a function to control a lighting state of a backlight based on each pixel These objects are achieved by turning off a light-emitting element in display of a black gray scale, and by providing a light-emitting element in each pixel and providing, in a pixel circuit, a function to individually control lighting and non-lighting of the light-emitting element depending on a gray scale to perform display When a backlight is provided in each pixel, a light-emitting element that is a backlight is turned off when a black gray scale is displayed, whereby reduction in contrast due to light leakage from a liquid crystal element can be prevented

Abstract: A display is backlit by a source having spatially modulated luminance to attenuate illumination of dark areas of images and increase the dynamic range of the display.

Abstract: An LED light source for LCD backlighting is described that recalibrates itself over time so that color and brightness uniformity across the backlight is maintained over the life of the backlight. The backlight contains clusters of red, green, and blue LEDs, each cluster generating a white point. In one embodiment, each color in a cluster has its own controllable driver so that the brightness of each color is a cluster is separately controllable. One or more optical sensors are arranged in the backlight, and the sensor signals are detected by processing circuitry to sense the light output of any LEDs that are energized in a single cluster. The measured white point and flux are compared to a stored target white point value and flux for that cluster. The currents to the RGB LEDs are then automatically adjusted to achieve the target level for each cluster. This process is applied to each cluster in sequence until the recalibration is complete. The recalibration takes place at various times over the lifetime of the backlight to offset the effects of LED degradation over time. Variations of this technique are also described.

Abstract: A backlight assembly includes a plurality of blocks and a driving substrate. Each of the blocks includes a plurality of light emitting diodes. Sides of adjacent blocks are fitted to each other. The light emitting diodes are mounted on the driving substrate.

Abstract: The embodiments disclosed herein comprise a plurality of modules and means to provide effect dynamic gamut mapping and backlight control. In one embodiment, a display system comprises: a transmissive display, said display comprising a plurality of colored subpixels wherein one such colored subpixel is substantially wide spectrum bandpass; a transmissive display controller, said display controller providing signals to said transmissive display to set the amount of transmissivity of each said colored subpixel; a backlight, said backlight providing illumination to said transmissive display; a backlight controller, said controller providing signals to said backlight to modulate the amount of illumination provided by said backlight to said transmissive display; peak surveying module for surveying image data and extracting the image gamut hull for providing intermediate backlight data signals to said backlight controller to match said image gamut hull; and a means for normalizing display image data signals according to said intermediate backlight data signals and providing said normalized image data as intermediate display data.

Abstract: Embodiments of the present invention generally provide m Methods and apparatus for reducing power consumption of backlit displays are described. Power consumption is reduced by dimming backlighting by a first scale factor and boosting pixel values by a second scale factor to compensate for the dimming. The scale factors may be constant values. Alternately, one or both of the scale factors may be determined based on pixel values for one or more frames to be displayed and/or one or more frames that have been displayed. For example, scale factors may be calculated based on an average linear amplitude of one or more frames of pixel values or from a maximum pixel value of one or more frames of pixel values. A graphical processing system is described including an integrated circuit capable of transforming a pixel value from a gamma-compensated space to a linear space.

Abstract: A backlight assembly emits light out of two light emitting faces using a light source such as side-emitting LEDs that send light into an optical guide or body of optical material that diffuses the light uniformly and emits bi-facially. In this way, two displays, such as LCDs, can be illuminated at the same time and the efficiency is increased. The backlight assembly can be incorporated into an eyewear system such as a binocular display system.

Abstract: An inventive rearview assembly for a vehicle may comprise a mirror element and a display including a light management subassembly. The subassembly may comprise an LCD placed behind a transflective layer of the mirror element. Despite a low transmittance through the transflective layer, the inventive display is capable of generating a viewable display image having an intensity of at least 250 cd/m 2 and up to 3500 cd/m 2 . The display includes a novel backlighting subassembly and novel optical components including a magnifying system, a depolarizer, a reflector, and a reflective polarizer. The display may be configured to display an image having edges contoured to correspond to the edges of the mirror element.

Abstract: In one embodiment, a display system includes a subpixelated display panel and a backlight array of individually controllable multicolor light emitters. When the display panel (160) comprises a multi-primary subpixel arrangement having a white (clear) subpixel, the backlight control (130) techniques allows the white subpixel to function as a saturated primary display color. In another embodiment, the display system may calculate a set of virtual primaries for a given image and process the image using a novel field sequential control employing the virtual primaries. In another embodiment, a display system comprises a segmented backlight comprising: a plurality of N + M light guides, said light guides forming a N x M intersections; a plurality of N + M individually addressable light emitter units, each of said N + M light emitter unit being associated with and optically connected to one of said N + M light guide respectively.

Abstract: In this paper, a sequential color light emitting diode (LED) backlight driving system for liquid crystal display (LCD) panels is proposed. Due to improvement on luminous efficacy, long life and wide color gamut, LED has gradually substituted for cold cathode fluorescent lamp as backlight. The proposed driving system adopts sequential color scanning scheme to improve light utilization efficiency by removing color filter. To meet display performance requirement that chromaticity variation Deltauv needs to be limited below 0.002, this paper also proposes a family of output current ripple free topologies to control the average driving current precisely, which in turn can reduce chromaticity variation. In addition, an LED bypass circuit is proposed to prevent LED arrays from open-circuit, and a driving voltage resetter is introduced to eliminate current spikes, improving backlight reliability and availability significantly. A forward-type output current ripple free converter has been built to sequentially drive color LED arrays, from which experimental measurements have verified the discussed performance and feasibility of the proposed system

Abstract: An image capture and display device is described The device includes a liquid crystal display panel, which can switch between two states, a display state and the capture state Wherein at least a portion of the display and a switchable diffuser become transparent in the capture state One or more image capture devices are located behind the display Holes or windows are provided in the backlight for the image capture devices to capture images of the scene in front of the device when in the capture state

Abstract: A light transmitting diffusing sheet can be used in backlighting systems for liquid crystal displays (LCDs). Such displays are typically used in televisions, computer monitors, laptop computers and handheld devices such as mobile phones. Embodiments of the light diffusing sheets are suitable for use with both cold-cathode fluorescent (CCFL) and light emitting diode based backlighting systems. Desired light transmitting properties in the light transmitting diffusing sheet have been achieved by modifying both the volume and surface features of the sheet. Embodiments of this invention when used as part of the backlighting assembly for a LCD system results in improved brightness and controlled viewing angles. In one embodiment, substantially asymmetric particles in the volume of the sheet are combined with a ridged structure on one surface of the sheet. The use of the sheet removes the need for separate prismatic films and diffusing sheets, while also optimizing the light transmitting properties of these two elements.

Abstract: In an optical sheet which is used for light control illumination in a backlight unit for a display, in order from an incident side of an illuminating light, there are provided at least a light scattering layer which scatters the illuminating light toward an outgoing surface side, an adhesion layer or an adhesive layer, a light reflection layer which reflects light scattered by the light scattering layer toward the light scattering layer side, and a lens sheet whose flat rear face is fixed to the other side of the light reflection layer, and in which a plurality of unit lenses are disposed on the surface. Opening portions corresponding to the respective unit lenses one-to-one are provided to the light reflection layer, and thickness of the adhesion layer or the adhesive layer is thinner than that of the light reflection layer.

Abstract: A system for powering and controlling an LED backlight, the system comprising: a control circuitry; a controllable power source responsive to the control circuitry; and a plurality of LED strings receiving power from the controllable power source, the control circuitry being operative to control the output voltage of the controllable power source responsive to a function of an electrical characteristic of at least one of the plurality of LED strings.

Abstract: Low profile, side-emitting LEDs (10) are described, where all light is efficiently emitted within a relatively narrow angle generally parallel to the surface of the light- generating active layer (14). The LEDs enable the creation of very thin backlights for backlighting an LCD. In one embodiment, the LED is a flip chip with the n and p electrodes (18) on the same side of the LED, and the LED is mounted electrode-side down on a submount (22). A reflector (34) is provided on the top surface of the LED so that light impinging on the reflector is reflected back toward the active layer (14) and eventually exits through a side surface of the LED. A waveguide layer (30) and/or one or more phosphors layers are deposed between the semiconductor layers (12, 14, 16) and the reflector for increasing the side emission area for increased efficiency. Side-emitting LEDs with a thickness of between 0.2-0.4 mm can be created.

Abstract: The thermostat includes a housing having at least a portion thereof illuminated by a light that changes color via a manual input. The light illuminates the display for easy readability while the variable color of the light allows a user to match the appearance of the thermostat to best complement the surrounding decor. User input elements provide for the manual adjustment of one or more characteristics of the light, such as visible color of the light. The light source comprises at least one LED for displaying a plurality of colors. In this case, to change the color of the light illuminating the translucent portion of the housing or backlighting the display, electronics within the thermostat control the drive signals to the LED in order to operate the LED to provide the desired color. The invention also contemplates filtering the light and manually adjusting the filtering to provide the desired aesthetics.

Abstract: A side light type backlight includes a light source including a plurality of LEDs, and a light guide plate. One of the end surfaces of the light guide plate is a light incidence surface at which a plurality of R-LEDs, a plurality of G-LEDs and a plurality of B-LEDs are arranged. LEDs satisfy the relationship of: a distribution range of light emitted from G-LEDs