直到目前为止的电位器,由于电刷在电阻器上滑行,造成摩耗,因而产生杂音,寿命亦短。图1所示(图2为其等效电路)为一种无电刷电位器,它是在导体和电阻器之间夹有受光照射而改变导电率的光导电体而成。当光致导电体被通过缝隙的光束照射以 Potentiometers so far, due to brush sliding on the resistor, resulting in wear and tear, resulting in noise, life expectancy is also short. Figure 1 (Figure 2 is its equivalent circuit) is a brushless potentiometer, it is between the conductor and the resistor is irradiated by light and change the conductivity of the photoconductor made. When a photoconductor is irradiated with a light beam that passes through the slit