A rotator position measuring system is provided to reduce the power consumption by using the light emitting diode and the photo diode in stead of the laser diode. A sensing part(210) is connected to one part of the rotor in which the scanning mirror and the axis of rotation are connected. The sensing part comprises a shadowing plate(216) which rotates corresponding to the rotation of the scanning mirror; an LED(212) irradiating the light in the specified direction; and a photo diode(214) which receives the light irradiated from the LED. The light irradiated from the LED is received to the photo diode. A sensing signal transform unit(220) converts the quantity of light light-received to the photo diode into the sensing signal. A controller(230) receives the sensing signal transformed from the sensing signal transform unit. The controller delivers the scanner control signal to a scanner control part(240).
