3-DIMENSIONAL GRAPHIC IMAGE REPRESENTATION OF HOLOGRAPHIC MICROSCOPICDISPLACEMENT PATTERN BY USING CUBIC SPLINE FUNCTION

For quantitative measurement of microscopical displacement of an objec t surface due to thermal stress, the holographic pattern measuring sys tem (HPMS) has been developed by the authors, which is combined both t he techniques of holographic interferometry and graphic image processi ng. In this measuring sytem, a cubic spline function was applied to ge t the 8-dimensional graphic image patterns of the distribution of the displacement. The displacement is calculated from the interferometry f ringe pattern, and the system was applied to deformation analysis of p rinted circuit board (PCB) due to thermal stress. The PCB deformation was expresed by 3-dimensional graphic image. A smooth curve could be o btained from rather less number of sampled data of interferometry frin ge.