高精度干渉縞解析システムと光学素子の評価

抄録

The use of fringe patterns is very powerful in extracting quantitative information, but sometimes extremely tedious and time consuming to evaluate quantitative data. This paper describes two types of interactive semi-automatic fringe analysis systems, and also describes the fringe scanning method of analyzing interferometric fringes with sufficient tilt introduced. One of the semi-automatic systems is based on a technique of fringe peak tracing, in which computer programs of preprocessing for noise reduction, fringe skeletoning and thinning, and interactive fringe order determination. Alternative is the one-dimensional version of fringe analysis. Only several analysis lines are read in for fringe peak detection and fringe orders are determined interactively. Fringe orders between the analysis lines are interpolated. These two are semi-automatic because of the interactive fringe order determination process, while in the method of fringe scanning all the processes of fringe analysis can be automated. Interferometric fringes with sufficient tilt are multiplied by reference fringe patterns to remove the tilt term in a computer. Phase profiles of interferometric fringes are obtained by summing up fringes multiplied with weights synchronous to the phase of the reference fringe. Finally, some examples of fringe data evaluation are presented, including 3-D plots of fringe data in which tilt term is removed, a point spread function and an optical transfer function.