Patent ID: 8194016

Claim:
An active matrix LCD, comprising: a pixel array comprising a plurality of pixel elements; and a voltage source supplying signal voltages to the pixel array for controlling brightness of the pixel elements in the pixel array and displaying an image; wherein different levels of the signal voltages are applied to adjacent pixel elements, respectively; wherein an averaged brightness of the adjacent elements is controlled to vary with the signal voltages following a first γ-curve to show an expected image when viewed at a normal position in front of the active matrix LCD; and the averaged brightness of the pixel elements in a first zone is controlled to vary with the signal voltages following a second γ-curve having a first constant level within a first specified signal-voltage range, and meanwhile, the averaged brightness of the pixel elements in a second zone of the pixel array is controlled to vary with the signal voltages following a third γ-curve having a second constant level within a second specified signal-voltage range, thereby changing a contrast of the image to a visibly unidentifiable degree when viewed at a skew position from the front of the active matrix LCD.