A CCD auto collimation angle measuring system based on field programmable gate array（ FPGA） is proposed. In this system

FPGA is used as processor core of system; using self-adaptive module to provide accurate waveform timing for CCD driving generator; edge detection algorithm is utilized to obtain pixel level edge of image;by using the least square fitting algorithm

circle centre position of facula is calculated; system design is completed with VHDL and MAX + plus II software. System testing and experiment prove that the system has characteristics of high precision and high integration.