A polarized image acquisition section 20 acquires a plurality of polarized images having different polarization directions. The polarized images show, for example, an input indicator for a user interface as a recognition target object. A normal line calculation section 30 calculates normal lines for individual pixels of the recognition target object in accordance with the polarized images acquired by the polarized image acquisition section 20. The normal lines represent information based on the three-dimensional shape of the recognition target object. A recognition section 40 recognizes the object by using the normal lines calculated by the normal line calculation section 30, determines, for example, the type, position, and posture of the input indicator, and outputs the result of determination as input information on the user interface. The object can be recognized easily and with high accuracy.