HIGH SPEED OPTICAL PHASE SCANNING METHOD

摘要

PURPOSE:To provide a high speed optical phase scanning method which can accomplish a scan at an interference fringe scan speed over 100m/s, compared with the corresponding value according to the conventional method which is around several tens of meters per, sec. CONSTITUTION:A special polygonal mirror 1 is formed by providing around a rotor 2 with a plurality of reflecting surfaces 3 positioned in the radial direction plane including the axis of the rotor 2, and such an optical path 14 is set that the light is projected to the reflecting surfaces 3 in the tangential direction to the rotor 2, and the phase of the light projected along the path 14 is varied at a high speed while the reflecting surfaces 3 move in the tangential direction to the rotor 2 substantially before and after the time when the light is projected perpendicularly to the reflecting surfaces 3 by rotating the rotor 2 at a high speed while projecting light flux to the reflecting surface 3.