PHOTOINTERRUPTER, ANGLE-OF-ROTATION DETECTING DEVICE AND DISPLACEMENT DETECTING DEVICE

PROBLEM TO BE SOLVED: To provide a photointerrupter, an angle-of-rotation detecting device and a displacement detecting device, which can position a a light-emitting element and a light-receiving element with high accuracy and have stable characteristics. SOLUTION: In an angle-of-rotation detecting device, a disc 34 provided with slits 35 is pivotally supported rotatably and a light-emitting element 31 and a light-receiving element 32 are counterposed with the disc 34 in between. A lead frame 10, which is extended from one end of the element 31 to one end of the element 32, is arranged on the outside of the disc 34, and couples integrally the elements 31 and 32 with each other in such a way that the optical axes of the elements 31 and 32 coincide with each other. In such a way, as the lead frame 10 couples integrally the elements 31 and 32 with each other, the optical axis of the element 31 is hardly shifted from the optical axis of the element 32, light can be detected with high accuracy and the stable characteristics of the detecting device can be ensured.