Patent ID: 7463297

Claim:
A liquid crystal display device comprising: a plurality of pixels; a plurality of optical sensors corresponding to each of the plurality of pixels, each optical sensor having a sensitivity R and each optical sensor being configured to convert an accepted light into an electric signal; a plurality of charge storage units corresponding to each of the plurality of optical sensors, each charge storage unit having a capacitance C and each charge storage unit being configured to store a charge in response to the electric signal converted by the optical sensor while the optical sensor has an initial voltage V applied; a plurality of retention units corresponding to each of the plurality of charge storage units, each retention unit being configured to retain a plurality of binary data, said binary data indicating whether an amount of charge stored in the charge storage unit is equal to or above a threshold voltage Vth; an image capturing control unit configured to generate a plurality of pixel data in a plurality of tone levels, based on the binary data outputted from each of the retention units of the plurality of adjacent pixels by image capturing for N times, wherein at least one value of sensitivity R, capacitance C, initial voltage V, and threshold voltage Vth in each of the pixels is set to a different value from a relevant value of other adjacent pixels; and wherein, in terms of p×q adjacent pixels of the plurality of adjacent pixels, an exposure time T(n) for an n-th (n=1, 2, . . . , N) image capturing by a specified pixel is calculated based on an average dark current I 0 , a reversal exposure time Tw in terms of a white standard subject for the specified pixel, a reversal exposure time Tb in terms of a black standard subject for the specified pixel, and with equations expressed as 1 T ⁡ ( n ) = 1 Tw - n ⁢ ⁢ Δ , Δ = ( 1 Tw - 1 Tb ) / N , and a parameter k, to determine an amount of variation of sensitivity for each of the plurality of pixels, is set in a range defined as 1≦k≦N−p×q+1 and, based on a standard value of sensitivity R 1 set in the specified pixel, a plurality of respective values of sensitivity R 2 to R p×q set in other pixels are calculated by equations expressed as R m + 1 = R 1 + m ⁢ ⁢ δ ⁢ ⁢ R , δ ⁢ ⁢ R R 1 = Δ · T ⁡ ( k ) · 1 1 - I 0 ⁢ T ⁡ ( k ) C 1 ⁡ ( V 1 - Vth 1 ) (where m=1, 2, . . . , p×q−1).