A novel method of driving an LCD simultaneously provides improved viewing angle and improved contrast. Multiple driving voltages are applied to the LC cell to optimize both the viewing angle and the contrast. A first voltage that is optimized for wide viewing angle is applied to the LCD. A second voltage that is greater than the first voltage is selected to provide maximum contrast in the LCD. The first and second voltages are alternately applied to In the LCD, resulting in a display that has high contrast and a wide viewing angle.
In a scrolling color projection system for displaying images represented by continuously updated frames of information, eg., video images, and employing a single, reflective electro-optic light modulator such as an AMLCD, flicker in the image caused by asymmetric electrical behavior of the light modulator is reduced without substantially reducing the brightness of the display, by addressing the modulator array at least twice during each frame period.
Viewing angle characteristics of a liquid crystal display (LCD) are improved by reducing the number of subpixels in an image with mid-tone luminance values. In a preferred embodiment, a first table of entries associating subpixel intensity values and subpixel luminance values for a LCD in at least one viewing angle direction is provided. A target intensity value is determined from the first table, corresponding to the average subpixel luminance over a small number of adjacent subpixels. A second table of entries associates the target intensity values with intensity values above and below the target. The adjacent subpixel intensity values are modified according to the second table, thereby reducing the number of subpixels with mid-tone luminance values. The subpixel data is preferably processed within a portion of an application-specific integrated circuit (ASIC), contained within the display module.
Adjustments are made to a displayed image in order to take into account user viewing angle. Brightness values for colors are stored within palette registers. In response to a user indicating a view angle change, brightness values stored in at least some of the palette registers are changed. As brightness values are increased, contrast between color shades is decreased.
