DISPLAY DEVICE AND A METHOD OF DRIVING THEREOF

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. The first mapping is arranged, for a pixel or a group of pixels, to map the image pixel data for the pixel or group of pixels to one of a first plurality of preselected drive signals including at least first and second pre-selected drive signals that drive, in use, the pixel or group of pixels of the display panel to produce different on-axis luminance values and that drive, in use, the pixel or group of pixels of the display panel to produce the same or similar off-axis luminance values at at least one off-axis viewing angle. This provides a private display mode. If a public display mode is desired, a second mapping of the image pixel data to a second plurality of drive signals is performed instead of the first mapping. The second 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 depend ent mainly on the image pixel data.