| 摘要 |
<p>PURPOSE:To have output characteristics closer to the ideal linear characteristics and improve an output sensitivity by a method wherein two three-terminal elements of which an optical potentiometer is composed are connected in parallel with each other in a point-symmetrical manner wherein the grounding electrodes of the respective three-terminal elements are opposite to each other. CONSTITUTION:A three-terminal element is composed of a resistance film 11, a photoconductive film 13 and electrode films 15 and 17. The two identical three-terminal elements 20A and 20B are connected in parallel with each other in a point-symmetrical manner wherein their grounding terminals are opposite to each other. Light spots A are applied to the same positions of the photoconductive layers 13 of the respective elements 20A and 20B and the two light spots are moved to the same direction so as to take out the outputs of the respective three-terminal elements in a differential manner. As the output is taken out as the differential resultant output of the outputs of the two three-terminal elements, the linearity of the output voltage is determined by synthesizing the linearities of the two three-terminal elements 20A and 20B. Generally speaking, the error of the output linearity of a single element is reduced by synthesizing the outputs of the two elements. The errors of the output characteristics of the individual three-terminal elements, therefore, are diluted and the satisfactory linear characteristics can be obtained.</p> |
