| 摘要 |
PROBLEM TO BE SOLVED: To reduce an area of a frame of a coordinate input device, and make a surface to be touched by a detected body fully flat.SOLUTION: A coordinate input device comprises: a plate-like light guide plate 10; an LED 4a that causes light to be made incident on the light guide plate 10; at least two imaging units; 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 units that has detected scattering of light caused by the finger. The LED 4a is arranged to be opposite to a back face of the light guide plate 10; and the coordinate input device further includes an optical coupling member 5 that has a sheet-like shape, and couples light beams emitted from the LED 4a to be made incident obliquely on the back face of the light guide plate 10. |
