Position detecting device

摘要

A conventional position detecting device for determining the position of a pattern having light and dark areas projected on a image sensor, in which the output signal from the image sensor is converted into a quantized signal through a sample and hold circuit. An improvement according to the invention is provided with a filter for cutting off the frequency components of the quantized signal above a clock frequency used for reading photoelectric outputs in the image sensor to convert the quantized signal into an analog signal to be used for determining the position of the pattern, whereby a high resolving power not limited by the length of each element of the image sensor is achieved.