| 摘要 |
PURPOSE:To prevent the output characteristic of adjusting signals from deteriorating and the adjusting accuracy from sinking, by forming a long hole in a rotary plate provided rotatably in such a way as intercepting between a light emitting element and a light receiving element. CONSTITUTION:A light emitting element 22 and a light receiving element 23 are installed facing together, and a rotary plate 26 provided with an approx. involute long hole 28 is installed in such a way as intercepting between these two elements 22, 23, and a control knob 13 is installed to turn and adjust this rotary plate 26. Further this is equipped with a light emitting element driver circuit 29 to drive the light emitting element 22 and an adjusting signal generator circuit 35 to give an adjusting signal Vout at a level according to the degree of light reception of the light receiving element 23. Accordingly adjusting signals Vout can be emitted at different levels by turning and adjusting the rotary plate 26 with the mentioned control knob 13. This prevents the output characteristic of adjusting signal Vout from deteriorating and the adjusting accuracy from sinking. |
