Abstract
A new method of designing an optical shutter for laser beams is described. The shutter is composed of a DC servomoter and a secter plate. The rotation angle of the secter is controlled by a photo-interrupter which detects the front and rear edge positions of each blade of the secter plate. The shutter makes a laser beam on and off according to the logic level of the control signal. The response time of the experimental setup is 12.5 ms for a He-Cd laser with a beam diameter of 2 mm. This shutter has very long lifetime and no optical loss for any types of lasers.
