フーリエ変換法を用いたレーザ計測に関する研究

Abstract

A laser measurment by Fourier transfer mothod is one of the simplest method for detecting a defect of the object spreading in two dimensions. Fourier transfer pattern of a metal mesh is measured in detail. The measured Fourier transfer pattern is compared with the callculated one. The period of the diffraction pattern, the peak value and the half width agree with the callculated one. In the edge part of the diffraction pattern, the measured value of the pattern is larger than the callculated one. Fourier transfer pattern of the object with a defect is compared with one of the object without a defect. The method for detecting a defect in a production process is disscussed.