Abstract: A switchable reflective colour filter is provided for use in a display device. The switchable reflective colour filter includes a plurality of sub-pixel regions of at least two colour types, each including a layer of phase change material which is switchable between a first state and a second state, the first and second states being two solid but structurally distinct states having different optical properties. Each sub-pixel region further includes two electrode layers, a mirror layer, and a spacer layer or air gap. The phase change material layer in each sub-pixel region is positioned between the two electrode layers, and separated from the mirror layer by the spacer layer or air gap. The switchable reflective colour filter may be incorporated into a display device including a pixelated switchable absorber. A luminance of coloured light reflected from any of the sub-pixel regions is controllably attenuated by the pixelated switchable absorber.

Abstract: A display device in which ambient light reflections, for example, from IPS or FFS type displays are reduced by a circular polariser (e.g., linear polariser combined with external quarter waveplate) to make the light circular polarized, as it traverses the multiple reflective layers between the polariser and LC layer, and then an internal quarter waveplate converts the light back to linear polarisation before it enters the LC, so the display can operate as normal, while the circular polariser absorbs unwanted reflections of ambient light from within the display.

Abstract: A display device includes control electronics and a pixellated liquid crystal (LC) panel. The control electronics receives inputs of main image data for a main image and side image data for a side image. The control electronics outputs combined image data combining the main and side images such that an on-axis viewer perceives from the combined image the main image, and an off-axis viewer perceives from the combined image the side image. The output image data comprises data values chosen from a set of available output data values for the pixels selected from multiple sets of available data values depending on at least on the side image data. For a pixel currently being processed, the output data value is chosen from the selected set of available output data values for which a resulting luminance value is closest to a target luminance value for the current pixel.

Abstract: An active matrix LCD display of the multi-pixel drive (MPD) type, in which a pixel comprises a plurality of sub-pixels with each sub-pixel of a pixel being associated with a respective storage capacitor address lines so that the voltage applied across an individual sub-pixel depends on both the signal voltage and the voltage applied to the associated storage capacitor address line, is driven such that the relationship between at least a first one of the capacitor line voltages and a second one of the capacitor line in a first display refresh period of the frame is different to the relationship between the first of the capacitor line voltages and the second of the capacitor line voltages in a second display refresh period of the frame. This allows the root-mean-square (RMS) voltage applied over the frame across a first of the sub-pixels to be controlled at least partially independently of the RMS voltage applied over the frame across a second of the sub-pixels, thereby providing increased resolution.

Abstract: A method of processing image data for display by a display panel of a display device comprises receiving image pixel data representing an image. In a first mode, the method performs a first mapping of the image pixel data to drive signals, each drive signal for driving a respective pixel or group of pixels of the display panel. The first mapping is arranged to produce an on-axis luminance pattern which is dependent mainly on the image pixel data and an off-axis luminance pattern which is wholly or substantially independent of the image pixel data.

Abstract: A color display includes multiple composite pixels, each composite pixel including sub-pixels of more than one color type. Sub-pixels of at least one of the color types are provided with differing luminance capability in different composite pixels. Each composite pixel may include red, green and blue sub-pixels having different luminance capability in different composite pixels. The differing luminance capability may be achieved by providing sub-pixels of at least one of the color types of differing relative area. An image data processing unit (IDPU) receives input image data of a standard format, and modifies the input image data into output image data for display to account for a discrepancy between the luminance capability based on the differing luminance capability or differing size of each sub-pixel, and a luminance capability as expected based on the input image data. The IDPU then outputs the output image data to control the composite pixels.

Abstract: A switchable reflective colour filter is provided for use in a display device. The switchable reflective colour filter includes a plurality of sub-pixel regions of at least two colour types, each including a layer of phase change material which is switchable between a first state and a second state, the first and second states being two solid but structurally distinct states having different optical properties. Each sub-pixel region further includes two electrode layers, a mirror layer, and a spacer layer or air gap. The phase change material layer in each sub-pixel region is positioned between the two electrode layers, and separated from the mirror layer by the spacer layer or air gap. The switchable reflective colour filter may be incorporated into a display device including a pixelated switchable absorber.

Abstract: A display device includes control electronics and a pixellated liquid crystal (LC) panel. The control electronics receives inputs of main image data for a main image and side image data for a side image. The control electronics outputs combined image data combining the main and side images such that an on-axis viewer perceives from the combined image the main image, and an off-axis viewer perceives from the combined image the side image. The output image data comprises data values chosen from a set of available output data values for the pixels selected from multiple sets of available data values depending on at least on the side image data. For a pixel currently being processed, the output data value is chosen from the selected set of available output data values for which a resulting luminance value is closest to a target luminance value for the current pixel.

Abstract: A switchable imaging device (1) has a first mode of operation in which the device performs an imaging function and a second mode of operation different from the first mode, for example a non-imaging mode. In the first mode of operation the device comprises at least one first region that performs a lensing action and at least one second region that at least partially absorbs light passing through the or each second region. The switchable imaging device (1) may be disposed in path of light through an image display panel (4). This provides a display that may be operable in either a directional display mode such as an autostereoscopic 3D display mode or a 2-D display mode, by controlling the switchable imaging device to be in its first mode or its second mode.

Abstract: A display device in which ambient light reflections, for example, from IPS or FFS type displays are reduced by a circular polariser (e.g., linear polariser combined with external quarter waveplate) to make the light circular polarized, as it traverses the multiple reflective layers between the polariser and LC layer, and then an internal quarter waveplate converts the light back to linear polarisation before it enters the LC, so the display can operate as normal, while the circular polariser absorbs unwanted reflections of ambient light from within the display.

Abstract: A color display includes multiple composite pixels, each composite pixel including sub-pixels of more than one color type. Sub-pixels of at least one of the color types are provided with differing luminance capability in different composite pixels. Each composite pixel may include red, green and blue sub-pixels having different luminance capability in different composite pixels. The differing luminance capability may be achieved by providing sub-pixels of at least one of the color types of differing relative area. An image data processing unit (IDPU) receives input image data of a standard format, and modifies the input image data into output image data for display to account for a discrepancy between the luminance capability based on the differing luminance capability or differing size of each sub-pixel, and a luminance capability as expected based on the input image data. The IPDU then outputs the output image data to control the composite pixels.

Abstract: A display device includes control electronics and a pixilated liquid crystal (LC) panel. The control electronics receives inputs of main image data for a main image and side image data for a side image. The control electronics outputs combined image data combining the main and side images such that an on-axis viewer perceives from the combined image the main image, and an off-axis viewer perceives from the combined image the side image. The output image data comprises data values chosen from a set of available output data values for the pixels selected from multiple sets of available data values depending on at least on the side image data. For a pixel currently being processed, the output data value is chosen from the selected set of available output data values for which a resulting luminance value is closest to a target luminance value for the current pixel.

Abstract: An active matrix LCD display of the multi-pixel drive (MPD) type, in which a pixel comprises a plurality of sub-pixels with each sub-pixel of a pixel being associated with a respective storage capacitor address lines so that the voltage applied across an individual sub-pixel depends on both the signal voltage and the voltage applied to the associated storage capacitor address line, is driven such that the relationship between at least a first one of the capacitor line voltages and a second one of the capacitor line in a first display refresh period of the frame is different to the relationship between the first of the capacitor line voltages and the second of the capacitor line voltages in a second display refresh period of the frame. This allows the root-mean-square (RMS) voltage applied over the frame across a first of the sub-pixels to be controlled at least partially independently of the RMS voltage applied over the frame across a second of the sub-pixels, thereby providing increased resolution.

Abstract: A method of processing image data for display on a display device having a multi-primary image display panel (2) comprises receiving image data constituting an image for display on the image display panel. In a first mode, signal voltages to be applied to sub-pixels of the image display panel are determined from the received image data and from a secondary data value for the pixel thereby to generate luminance variations perceivable at a first viewing position (5) but substantially not perceivable at a second viewing position (3).

Abstract: A display device is provided that comprises a liquid crystal display panel (2) for displaying an image by spatial light modulation. The image is represented by a plurality of image elements each having an image data value (7). The display device further comprises a display controller (1) arranged to determine a signal voltage to be applied to the panel (2) for each image element in dependence upon its image data value (7) and a secondary data value (8) for the element, there being a predetermined mapping between the data values and the signal voltage. The secondary data values (8) are arranged to vary across the image so as to introduce variations in luminance as a result of the mapping. The mapping and secondary data values (8) are mutually arranged to take account of the signal voltage to on-axis luminance response of the panel (2) so that the luminance variations introduced on-axis tend to balance locally through spatial averaging to, and hence would not be perceivable by, an on-axis viewer (3).

Abstract: A method of processing an image comprises: receiving pixel data constituting an image, the pixel data including at least four sub-pixel color components having respective data values, and modifying one or more of the sub-pixel color component data values. The data values of corresponding sub-pixels from two pixels are modified in opposite directions to one another and such that the overall luminance of the display panel appears substantially unchanged to an on-axis viewer of the display panel.

Abstract: A display includes a backlight portion having at least one broad spectrum emitter (such as white) and at least one narrow spectrum emitter (such as red, green, and blue), a liquid crystal panel for displaying an image by spatial light modulation, and control electronics configured to receive input image data and output control signals to both the backlight portion and liquid crystal panel. The control electronics is configured to use color rendering capabilities of the liquid crystal panel under illumination from each of the emitter types individually to calculate a minimum power combination of emission from each emitter type required to display the input image data. The control electronics is further configured to modify the input image data according to the calculated minimum power combination of emitter powers so a resulting display of colors in the image data remains despite changing illumination conditions.

Abstract: A display includes a backlight portion having at least one broad spectrum emitter (such as white) and at least one narrow spectrum emitter (such as red, green, and blue), a liquid crystal panel for displaying an image by spatial light modulation, and control electronics configured to receive input image data and output control signals to both the backlight portion and liquid crystal panel. The control electronics is configured to use color rendering capabilities of the liquid crystal panel under illumination from each of the emitter types individually to calculate a minimum power combination of emission from each emitter type required to display the input image data. The control electronics is further configured to modify the input image data according to the calculated minimum power combination of emitter powers so a resulting display of colours in the image data remains despite changing illumination conditions.

Abstract: A display comprises independently addressable pixels, a pixel comprising first and second electrodes (12a,12b) disposed on a first substrate and spaced apart from one another. A counter electrode (22) is provided on a second substrate, with an electro-optical material provided between the first substrate and the second substrate. A controller, in use, applies a first voltage to the first electrode of the pixel, a second voltage different to the first voltage to the second electrode of the pixel, and a third voltage to the counter electrode of the pixel to define in the pixel at least one of a first region (18a), a second region (18c) and a third region (18b). The first, second and third voltages are selected such that an area of the first region, second region and third region or each of the first, second region and third region defined in the pixel produces a desired greyscale level for the pixel.

Abstract: A method for modifying an image to be displayed on a display includes receiving an image to be displayed on the display having a backlight and a transmissive panel. A backlight signal is provided to the backlight for causing the backlight to selectively illuminate different portions of the backlight with different characteristics. The characteristics include at least one of a different color and a difference luminance. A panel signal is provided to the panel for causing the transmissive panel to selectively change its transmittivities. At least one of the backlight signal and the panel signal are modified in a manner to reduce off-axis artifacts.