In this paper

the digital image correlation tecniques are investigated for measuring the positions of the CCD elements. Using the real element images

the accuracy and noise immunity of several similarity measures are analyzed

and the proper similarity measures are find out

which have the matching accuracy of 1 pixel. The fast matching algorithms and the hardwares are used to improve the mathching efficeiency. The SSDA method is introduced to our measuring system

and its problem of the choice of the thresholds is investigated and solved. Another fast matching approach called Two-stagge-Template-optimizing Image Matching is put forward

which has no problems of the threshold choosing and has constant mathching speed. In the aspect of hardware

an accelerating card using TMS320C25 digital signal processor is designed to configurate a host/coprecessor high -speed system with the host computer.