In this paper , all kinds of diameter gauge were reviewed through extensive reading of the technical papers and reports . an optical diameter gauge using ccd with high speed and high precisely was designed 本文通过广泛阅读资料和调研深入了解了目前各种光学测径仪器的发展现状,并研制了一种基于激光和ccd器件的高速度高精度测径仪。