| 摘要 |
PROBLEM TO BE SOLVED: To make the size in a longitudinal direction of a semiconductor chip of a photodetector array small and prevent generation of crosstalks by arranging each photodetector zigzag on the semiconductor chip. SOLUTION: A semiconductor chip 1 has a plurality of photodetectors 2 of an array for receiving a light passing slits of a code plate 4 of an optical encoder, which are arranged zigzag in a right-left direction to a center line 3 of the chip 1. The detectors 2 are separated to right and left via the center line 3 and shifted in an up-down direction orthogonal to the center line 3 not to be aligned straight in the right-left direction. Each detector 2 is formed in a state to be registered with a track 5 of every bit where the slit is formed. A relationship of a first interval H and a second interval (h) of a minimum distance of adjacent elements 2 is set to be H>h. Even when the longitudinal interval (h) of adjacent detectors 2 is made smaller than conventionally, the interval H of the detectors is maintained and no electric crosstalk is brought about.
|
