Patent ID: 8530872

Claim:
An optical position detecting device comprising: a translucent member that has first and second surfaces opposite to each other; a plurality of light source sections that have first and second sets of light source sections, that emit detection light and that are located in a first area next to the first surface of the translucent member so as to be separated in a first direction intersecting an emitting direction of the detection light; a light detection section that is located in the first area and that receives reflected light reflected by a target object located in a second area next to the second surface of the translucent member; a light source driving section that alternately turns on the first set of light source sections and the second set of light source sections; and a position detecting section that determines a position of the target object based on first intensity of reflected light that is formed by the detection light emitted by the first set of light source sections and second intensity of the reflected light that is formed by the detection light emitted by the second set of light source sections, wherein the light detection section is surrounded by the plurality of light source sections in the first direction, wherein each of the first set of light source sections is located closer to the light detection section than each of the second set of light source sections, and wherein the position detecting section determines the position of the target object by comparing between the first intensity and the second intensity.