Optical Position Detection Apparatus

An optical position detection apparatus capable of detecting a pointing position of a pointer to be input to a detection area having substantially a rectangular shape, the apparatus comprising:

• a retroreflective member that is provided in the pointer or disposed so as to cover two predetermined sides of a perimeter of the detection area;
• and
• a detection unit that is disposed adjacent to a corner opposite to the two predetermined sides of the perimeter of the detection area and detects a pointing position of the pointer by using reflection light reflected from the retroreflective member, the unit including at least two detection sections each having a light source section that emits light traveling along the surface direction of the detection area and a camera section that images reflection light emitted from the light source section and reflected by the retroreflective member,
• the light source section having an irradiation angle wide enough to irradiate the two predetermined sides of the perimeter of the detection area with light, and
• the camera section being disposed close to the light source section and having a viewing angle wide enough to image the two predetermined sides of the perimeter of the detection area.