| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an input device capable of accurately distributing light from a light source to two sides of a frame adjacent to the light source at a predetermined ratio, even if misalignment in a horizontal direction occurs in alignment between the light source and a bifurcated optical waveguide core on a light emission side. <P>SOLUTION: An input device has a bifurcated optical waveguide core C1 on a light emission side of a frame-shaped optical waveguide 10 arranged around a rectangular detection space S. The bifurcated optical waveguide core C1 includes: a common part 1 on a light incident side adjacent to a light source 20 provided at a corner part 10z; and two branching core parts 4, 5 branching from a branch point on a terminal side of the common part and arranged on two sides of the frame. If a core width W of a light incident end face (optical coupling surface) 1a of the common part 1 is 1 mm or more, a distance L from the light incident end face 1a to the branch point J is set 3 mm or more, and if the core width W of the light incident end face 1a is less than 1 mm, the distance L from the light incident end face 1a to the branch point J is set three times the core width W of the light incident end face 1a, or more [(L/W)≥3]. <P>COPYRIGHT: (C)2013,JPO&INPIT |
