SURFACE SHAPE MEASURING METHOD AND ITS DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a surface shape measuring device capable of speedily and accurately measuring a recessed and projecting shape on a measuring object surface. SOLUTION: A band path filter 11 restricts white light from a white light source 10 to a specific frequency band region. The white light is radiated through a driving portion 24 to a reference surface 15 and the measuring object surface having varying relative distance, and the variation of the optical path difference generates interference stripes. A CCD camera 19 picks up images of the interference stripes and the measuring object surface. A CPU 20 samples intensity of interference light varying at a specific position of the measuring object surface 31 in a predetermined sampling interval based on a band region width of the specific frequency band region. A specific function having a peak position matching a peak position of the interference light is estimated, based on the band region width of the specific frequency band region. By determining the height of the peak position of the specific function, a recessed and projecting shape on the measuring object surface 31 is measured.