When processing images with a computer for pattern understanding and other purposes, several problems are generally pointed out. Important ones among them are; (1) the difficulties in subsequent analysis and the accuracy of the result depend greatly on the quality of the input data, (2) large quantities of digitized data need to be dealt with, and (3) complex analysis and usually a long processing time are necessary. For these reasons, a highly efficient computer along with peripheral equipment is usually required. However, such high performance machines are not always available. This is particularly true in the case of the application of image processing to certain practical engineering fields. Thus, image processing techniques are not sufficiently utilized in practical engineering analysis in spite of its usefulness in visualization of phenomena. In this paper, the authors develop and construct an input/output system using a microcomputer for practical application to photoelastic fringe patterns in the field of strength of materials. This system can be easily operated by engineers not specialized in computer. It is applicable not only to interference fringe patterns but also to many other areas.
