Wafer rotation speed measuring device, method and system

The invention provides a wafer rotation speed measuring device, method and system. The device includes a driving wheel assembly, a driven wheel assembly and a measuring assembly; the measuring assembly is arranged on the driven wheel assembly; the driving wheel assembly is used for driving a wafer to rotate through the rotation of the driving wheel assembly so that the driven wheel assembly can bedriven to rotate with the rotation of the wafer; the measuring assembly is used for performing frequency measurement on pulse signals outputted from the rotation of the driven wheel assembly, whereinthe pulse signals are signals converted from the angle displacement of the output shaft of the driven wheel assembly; and the frequency measurement result of the measuring assembly is corresponding to the rotation speed of the wafer. According to the wafer rotation speed measuring device, method and system of the invention, the rotation speed of the wafer is measured based on the frequency measurement of the pulse signals