Principle and application of photoelectrical encoders

As the important parts of numerically-controlled machines, the position detection cells have their applications ondetecting displacements and sending the feedback signals to be compared with the command signals from numerically-controlled devices. Photoelectrical encoders are revolving position sensors and are used widely for measuring angular displacements and angular rates. The numerically-controlled machines manufactured and used at present adopt the half-close-cycle control modes mostly. Most displacement encoders are manufactured to set in the top places of drive motors and measure the actual positions and displacements of actuators indirectly