Optical CPC sensor using photo diodes. 

A sensor that measures one end of a strip to guide so that one side of the strip can always be wound uniformly, or to guide so that the strip is placed in the middle. 

It can control fabrics with various heights of length, middle and short length, various widths, and it is precise with high accuracy, and also robust against nearby scattered reflection. 

Use in combination with PR-LD series. 

20151207​