Shape Error Measurement Using Ray-tracing and Fringe Scanning Method

点击翻译按钮获取中文摘要

A free-form is used for manufacturing industrial products to improve on their own function. Measurements of the free-form are important to obtain the products of quality. Since accuracy required for measurements becomes high, it is necessary to measure in a processing and on a processing machine. In this report, a grating projection method modified from the Hartmann test is proposed to measure the free-form precisely. And furthermore, measuring systems and software are developed to make the proposed method fit for practical use. Results are follows.1) Development of a free-form measurement machine:The measurement machine was developed based on the proposed principle. Since the developed machine include a liquid crystal panel, an interval and a phase of projected grid patterns are electrically variable.2) Development of basic program to analyze a shape:A design program of grids and an analyzing program of modified grids are developed. Shapes of samples were measured with the developed programs. And the results was compared with results measured by general measurement machine.3) Development of an algorithm for analyzing at high speed:Data obtained by the proposed method were inclination of form under test. The form integrates the inclination. Therefore a highly precise integration method appropriate for quadrature is proposed. We provide the coefficient conditions for rendering the integration error smaller than that of Simpson's 3/8 rule ; this is a typical integration method. In addition, the advantage of this method is demonstrated by simulation experiments.A prospect to make practicable was obtained from the results.