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Aluminum flyer with thickness of 50μm and diameter of 1mm had been driven successfully by high-power Nd:Glass laser system. Average speed of the flyer was detected by piezoelectric Polyvinylidene Fluoride (PVDF) transducer, which reached 6.67km/s. Extent of damage to protective materials of spacecrafts was studied after they were hit by the driven aluminum flyer. The protective materials of spacecraft were damaged structurally in our experiment, and the damage observed under the microscope was also shown. It could be seen that the flyer knocked a tiny hole with diameter of about 1mm in the protective cellular board, and there were traces of impact damage around the tiny hole, which indicated that protective materials of spacecrafts would be damaged structurally when they were hit by flyer with size of 1mm. At the same time, the hyperspeed flyer still had good integrity and flatness. The results showed that laser-shockwave-driven hyperspeed flyer technology could be used as an effective experiment means to simulate high-speed space particles, which made it feasible to establish a set of simulation device of laser-shockwave-driven hyperspeed flyer for the research of protective materials of spacecrafts on the ground.

A glasses defect inspection system is researched and developed according to the principle of light scattering and visual inspection method, which is based on the machine vision. In order to achieve the classification of glasses, the functions of image acquisition, simple image processing, grading and sorting of glasses are designed in this system. Operation of parallel structure is adopted in this system. Forwardlighting by low-angled-ring-LED is used to get the clear images of the defects in or on the surface of the glasses, such as speckles, impurities, feathers and so on. Image processing and glasses grading based on normalization algorithms are used to acquire the identifying information of various defects of glasses. Experiment results show that the detection system, which can detect all the kinds of defects of the glasses, has high processing speed and strong anti-interference capacity. The size of the smallest defect that can be detected by the system is 0.03mm, and the average detection time of each glass is less than 2s.

For high power and repetitive Nd:Glass laser, there would appear serious thermal effect due to the significantly-enhanced pumping optical power density in laser rod, which would induce thermal double refraction, phase distortion, thermal focusing, thermal depolarization, etc. Thus, the laser output power and beam quality would be influenced severely. Influence of thermal lens effect and depolarization effect caused by thermal stress double refraction on laser beam were studied in this paper for high power and repetitive laser. In the experiment of thermal lens effect, change of the laser spot by thermal lens effect was recorded after a TEM00 He-Ne laser beam passing through the Nd:Glass rod pumped by Xe lamp, and the corresponding optical compensator was applied to eliminate the thermal lens effect to improve the beam quality. Configuration of polarizer was designed in our experiment to research the depolarization effect caused by thermal stress double refraction. First, emergent light distribution and loss factor caused by double refraction was calculated according to the theoretical model. Then the exiting cone-shaped polarized light intensity distribution was obtained through the experiment. It could be obtained from the experiments that thermal lens effect and depolarization effect caused by thermal double refraction would reduce the output laser beam quality to varied extents. As the number of laser pulses increased, thermal effects began to emerge and the output laser energy apparently decreased; when the thermal effects steadied, the output energy would be tending towards stability.