| 摘要 |
PROBLEM TO BE SOLVED: To provide a position sensor which is superior in terms of positional accuracy of detected depressed position and depression detection sensitivity and which has an optical waveguide that sinks in when small pressing force is applied and whose cores and undercladding layer are free from plastic deformation even when strong pressing force of a 13 N load is applied on the optical waveguide and are capable of quickly returning to an original shape when the pressing force is released.SOLUTION: A position sensor has: an optical waveguide W comprising a grid of cores 2 supported on a square sheet-like undercladding layer 1 and covered by an overcladding layer 3, an elastic layer R having a durometer hardness of 20-40 and a modulus of repulsion elasticity of no less than 70% provided on a back surface of the optical waveguide W; and a light-emitting element 4 and light-receiving element 5 coupled to respective end faces of the cores 2. The cores 2 have an elasticity modulus greater than those of the cladding layers 1, 3, a ratio of thickness to width of no less than 2, and a tensile elongation of 3-10% in the elastic range. The undercladding layer 1 has a tensile elongation of 5-140% in the elastic range. |
