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Accurate calibration of camera intrinsic parameters is crucial to various computer vision-based applications in the fields of intelligent systems, autonomous vehicles, etc. However, existing calibration schemes are incompetent for finding general trend of the variation of camera parameters due to common physical changes. In this paper, it is demonstrated that major and minor variations due to changes in focal length and camera pose, respectively, can be identified with a recently proposed calibration method. It is readily observable from the experimental results that the former variations have different trends (directions) of principal point deviation for different types of camera, possibly due to different internal lens configurations, while the latter have very similar trends in the deviation which is most likely due to direction of gravity. Finally, to confirm the validity of such unprecedented findings, 3D to 2D reprojection errors are compared for different methods of camera calibration.

High intensity ultra-short pulse UV laser system found many applications in atomic researches, picosecond phenomena and bio researches. We present a high intensity ultra-short pulse UV laser system that not only can generate single amplified high intensity ultra-short pulse UV laser system, but also can be operated in repetitive mode up to tenths pulses per second. Our complete laser system could also be extract as femtosecond ultra-short pulses sub-system, three amplifiers four passes single amplified medium to high intensity ultra-short pulse laser sub-system, and ultimately, high intensity ultra-short pulse UV laser system. Techniques of single amplified high intensity ultra-short pulse of this laser system are presented and characterized.

Single amplified ultra-short laser pulse is very important in basic scientific researches as well as in ultra-high power laser applications. The high intensity ultra-short laser pulse usually comes from the mode-locked pulses train. It is important to develop a laser amplifier configuration that can optimally amplify single ultra-short laser pulse. We present in this research, first by controlling the synchronization of the amplifiers chain, and then optimally adjust the shape of amplified spontaneous emission of each amplifier, we can select the single amplified ultra-short laser pulse out of the seed ultra-short pulses train and boost the laser pulse to the maximum power amplification. An adjustable repetitive single pulse high intensity ultra-short pulse UV laser system was developed and the laser outputs were extracted at various ends and characterized in detail.