Motor or generator

摘要

The motor comprises an optical arrangement to determine the distance moved or angle of rotation. The arrangement has diffractive or refractive elements to split a light beam (10) into at least two beams (11) for which a diffracting scale (2) is provided. The resultant diffracted and interference beam (12) is monitored by a sensor (3.2) and converted into electrical signals which are processed electronically. The diffractive scale is formed on the surface of one (1) of the two parts. The scale can be formed on a rotating shaft and take the form of a measurement grating with lines in the shaft surface running parallel with the axis of rotation