To enable acquisition of image data in multiple tone levels in a short capturing time, a liquid crystal display device 1 includes a photodiode having sensitivity R, a capacitor having capacitance C and configured to store a charge in response to an electric signal converted by the photodiode in a state where an initial voltage V is applied thereto, a SRAM configured to retain binary data which indicate as to whether or not an amount of charge stored in the capacitor is equal to or above a threshold voltage Vth, an image capturing control unit 5 configured to generate pixel data in multiple tone levels based on the binary data outputted from the SRAM of a plurality of adjacent pixels. Here, at least any one value of R, V, C, and Vth in each of the pixels is set to a different value from relevant values of other adjacent pixels.