Absolute Shaft Encoders
A shaft encoder is an electro-mechanical device used to measure the rotation angle of mechanical shafts. Absolute shaft encoders can use mechanical contacts or optical sensors to measure the rotation angle and return a unique digital value for each angular position of the shaft. As opposed to incremental (or relative) shaft encoders, absolute shaft encoders always retain the absolute position of the shaft, even if the machine in use exeriences a power shutdown or other operational interruption.
Suppliers of Absolute Shaft Encoders