Principal And Application Of Aspheric Surface Measuring Instrument In Miniature

The precision of polishing of optics depends on the precision of grind. The general procedure of processing aspheric optics is coarse grinding , fine grinding , polishing and measuring. The general measure method of aspheric optics is done after fine polishing. When the error between actual surface and theoretic surface is big, we must grinding the optics again, then polishing, measuring...It's too complex! If we had a measuring instrument which could measure the surface of aspheric optics after fine grinding, the procedure of processing aspheric optics would be simplified and the cost would be reduced. It is more important to mass production of aspheric optics.In this paper one aspheric surface measuring instrument is discussed. Some of aspects connected with measuring instrument are introduced such as the work theory of aspheric surface measuring instrument, the causations of machine error and the solving ways of these causations, the precision of instrument confirming, the result and analysis of experiments and the function of this instrument in practical production.Commonly, the precision of grind machine could reach to 2um after modifying and grinding for second time. So we designed and assembled this aspheric surface measuring instrument to get error function as compensation documents of grind machine to assure the precision of grind of optics. By many experiments and analysis, we could prove that our aspheric surface measuring instrument in miniature reaches the request of designment. It could meet the measuring requirement of laboratory and optical shop for grinding surface, Its practical testing precision is 1-2um. Meanwhile it is suitable for final testing of optical element with reasonable accuracy.This aspheric surface measuring instrument in miniature have been used topractical production, and have exerted good influence on production quality and cost.