| 摘要 |
An optical potentiometer has a rotatable disc 15 with first and second variably light transmissive windows 41, 42, Fig. 5, a source of light 33, 34 mounted on one side of the windows. Corresponding first and second light responsive devices 36, 51 are mounted on the other side of the window in such a fashion that only one of the light responsive devices receives energizing light at a time. A handle (11, Figs. 1 & 2) moves the disc so that the first and second variable light transmissive windows 41, 42 pass the corresponding first and second light responsive devices 36, 37. A dwell period may be provided between the times when the first and second light responsive devices receive energizing light. <IMAGE> |
