| 摘要 |
PROBLEM TO BE SOLVED: To ensure a detection area in light receiving means for detecting scattering light, while preventing direct incidence of light emitted from a light source.SOLUTION: A coordinate input device comprises: a plate-like light guide plate 10; a light source unit 4A that causes light to be made incident on the light guide plate 10; an imaging unit 20; and a detection unit that detects, when the surface of the light guide plate 10 is contacted by a finger, coordinates of a contact position of the finger on the surface of the light guide plate 10 on the basis of output of the imaging unit 20 that has detected scattering of light caused by the finger. The light source unit 4A is arranged closer to an outer peripheral side of the light guide plate 10 than an effective visual field area 20A of the imaging unit 20. |
