With the development of industry,there are more requirements of accaracy of taper thread plug gauge's manufacture.How to improve the precision of measuring is an important problem.In this article,we analyze the contact measurement and non-contact measurement for taper thread plug gauge,and the think that using CCD vidicon to detect and measure taper thread plug gauge is a new non-contact measurement method.with the development of machine vision,mode distinguish,image processing and so on,this new method wil...