Research on distortion measurement and calibration technology for TV-seeker

In order to satisfy the detective distance requirements of TV-seeker, dual-CCD scheme is used in its optical imaging system. But the distortion of CCD camera has seriously affected on the image quality, which can not get high-precision image of registration and mosaic. Therefore its quantitative measurement and calibration is the key to the attack accuracy of the precision guided weapon. Aiming at the problem as distortion of TV-seeker, firstly Tsai two-stage method based on radial constraint is used to calibrate the CCD camera whose interior parameter and exterior parameter have been determined. The high performance electronic target is established whose advantages are high contrast, high brightness, excellent uniformity and so on by use of TFT-LCD spatial light modulator and visible image display technology. On basis of this, the distortion measurement system is formed to measure the CCD camera. Then polynomial model is established by applying the inversion algorithm and the measured distortion is calibrated by the least squares fit. The calibrated result shows that the measurement precision using this algorithm is higher than that using the positive one obviously and the average distortion after calibration is better than 0.15%. © 2009 SPIE.