METHOD AND EQUIPMENT FOR MEASURING PLANE SHAPE

摘要

PROBLEM TO BE SOLVED: To provide a method and an equipment for measuring the shape of a plane having area larger than that of a measuring aperture while splitting by scanning the aperture in which the error is not increased at a joint even if the number of synthesizing times is increased. SOLUTION: An interferometer 10 having a measuring aperture opening to the side of a plane 11a to be measured is fixed movably to a direct driven stage 12 and scanning is performed by driving the direct driven stage 12 in the X direction. An angle reference mirror 13 for measuring the rotation of the interferometer 10 about the Y axis is applied to the side face of the interferometer 10 in the X direction. Furthermore, an autocollimator 14 for measuring the rotational angle of the interferometer 10 about the Y axis is arranged at a position where the autocollimator 14 faces the angle reference mirror 13 from the X direction. The interferometer 10, the direct driven stage 12 and the autocollimator 14 are connected with a calculation control section 15.