The information processor includes an input unit having an illuminating part and an image pickup part, and an input medium having an input surface on which inputting of information is carried out by the input unit which has position coordinates on the input surface coded by a dot pattern. The input unit irradiates light from the illuminating part onto input surface of the input medium. The irradiated light reflects off the dot contained in the dot pattern which is picked up by the image pickup part, and position information of the dot pattern is obtained. The input unit further has an input unit angular position measuring part that measures an angular position of the input unit when the light is irradiated. Based on corrected position information obtained by correction processing based on the angular position, input information, that is specified by the position coordinates is obtained.