Measuring method of angle-measurement precision for fire control dynamic performance test system

Distortion of optical system makes focal length of advanced fire control dynamic performance test system different at different FOVs, and influences angle-measuring precision. A focal length calibration formula based on leastsquare method was used to obtain a unified focal length for all the FOVs and the influence of the distortion was reduced. For a specific fire control dynamic performance test system, its measurement result was 2.34″ by using the method, which improved angle precision from 20 to 5 arc-second. It is proved that the modified calibration formula can improve the performance specification of fire control dynamic performance test systems.