Currency validator using a photocoupler for image recognition using cylindrical lens

摘要

A photocoupler for image recognition is disclosed which comprises a case, a pair of a light emitting diode and a light sensitive transistor, and a cylindrical lens which forms the light emitted from the diode into a linear light image on a surface of an object having printed pattern. After reflected on a surface of the object, the linear light image passes through the cylindrical lens and is received by the light sensitive transistor.