Patent ID: 7414608

Claim:
An image display apparatus for displaying an input video signal on a passive light modulation part including a light source, said apparatus comprising: an input signal processing part for amplifying said input video signal so as to increase a difference between a maximum brightness level and a minimum brightness level, a characteristics detection part for detecting a maximum brightness level, a minimum brightness level, and an average brightness level of said input video signal; and a control data generation part for calculating a gain for signal amplitude adjustment and a shift amount of a DC level, said gain for signal amplitude adjustment being for increasing a difference between said maximum brightness level and said minimum brightness level to a dynamic range with reference to said average brightness level, and said shift amount of a DC level being for allowing said input video signal to fall within said dynamic range, wherein said input signal processing part is operable to adjust the amplitude and DC level of said input video signal in accordance with said gain for signal amplitude adjustment and said shift amount of a DC level, said passive light modulation part and said input signal processing part are interconnected such that a video signal outputted from said input signal processing part is inputted to said passive light modulation part, and said image display apparatus is operable to adjust a brightness of said light source such that an average brightness level of a screen is equal to an average brightness level of said input video signal.