PURPOSE: To ensure the judgment of the position of a body, by arranging a plurality of the pairs of light sources and sensors in the same panel, and arranging a reflecting mirror, which reflects the light from each light source to the side of said sensors so as to face said panel.

CONSTITUTION: A light-source driving signal is inputted into a driver D11 through a power signal line I. Said driver D11 operates only the pair of a light source L11 and a sensor S11. Then the light source L11 emits light. Namely, other light sources L12... do not emit light. At this time, the reflected light from a reflecting surface 8a is received with the sensor S11 forming the pair. It is judged that a body 11 is not present at the coordinate position where the pair of the light source S11 and the sensor S11 are present. Then, the pair of a light source L12 and a sensor S12 are driven with a driver D12, and light is emitted from the light source L12. Since the body 11 is present at the position corresponding to the light source L12, the light, which is emitted from the light source L12, is absorbed in the body 11. It is judged that the body 11 is present at the coordinate position where the pair of the light source L12 and the sensor S12 are present. In this way, the spatial position of the body 11 can be detected positively.