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A compact end-pumped Electro-optical Q-switched Nd:YAG laser was designed in this paper. In order to achieve compact construction, laser diode arrays(LDAs) with collimated fast axes were used as pumping source. A spherical lens with a focal length of 40 mm and a cylinder lens with focal length of 25 mm were used as a group for the coupling lens. The LDAs' beam profiles on the incident and exit faces were calculated using Tracepro software. The simulation results indicate that when taking a Φ 6 mm×30 mm Nd:YAG with a doping concentration of 1.0at.% as the gain medium, the spots on the incident and exit faces were 5 mm(slow-axis)×4.5 mm(fast-axis) and 3 mm(slow-axis)×6 mm(fast-axis), respectively, and the absorption pumping power was about 83%. Dynamic temperature field distributions of Nd:YAG larer in 360 s at 22℃ and 60℃ were simulated by Ansys software. Output pulsed energy of 30 mJ and 25 mJ were achieved while the repetition frequencies were 30 Hz and 50 Hz, corresponding to a slope efficiency of 11.6% and 14.71%. The pulse durations were 18 ns and 16 ns, respectively. The experimental results show that the designed compact laser in this paper can achieve stable pulse laser output.

介绍了 Ф 420 mm熔石英高次非球面透镜的加工与检测方法。对现有数控加工工艺进行了优化，通过分工序加工方式，依次采用机器人研磨、抛光和离子束修形技术完成了透镜的加工。进行非球面透镜检测时，考虑透镜的凹面为球面，利用球面波干涉仪对其面形进行了直接检测，剔除干涉仪标准镜镜头参考面误差后，透镜凹面的精度达到0.011λ-RMS；针对透镜的凸面为高次非球面，采用基于背后反射自准法的零位补偿技术对其进行面形检测，其精度达到0.013λ-RMS。最后，采用一块高精度标准球面镜对加工后透镜的透射波前进行了自消球差检测，得到其波前误差为0.013λ-RMS。试验结果表明，非球面透镜各项技术指标均满足设计要求。所述工艺方法亦适用于更大口径的非球面透镜及其他类型非球面光学元件的高精度加工.

A method based on optimization functions was proposed to improve the attitude measurement precision of a plane.First,the same feature that the plane was projected at two measuring stations was acquired by the template matching method.The coordinate value of the same feature for the plane was obtained by intersecting at a launching coordinate,and the initial value of the plane attitude was estimated in term of the characteristic triangle of the plane in space.Then,the object coordinate of the plane was established,the image coordinate according to the feature of plane was calculated by using a colinear equation and the least difference between the re-project result and an actual image was regarded as the optimizing goal function.Finally,the iterative method was used to improve the precision of the attitude parameter of a target.Experimental results show that the measuring error of the attitude angle is less than 0.1 ° when the axis of the plane imaging is more than 500 pixels.As compared with the middle axis method and the direction vector method of angle bisector lines,proposed method has a correct mathematical model,reasonable algorithm and can improve effectively the measurement precision of the plane.

For the special structure of cylindrical inner surface of a Wolter-Ⅰ grazing mirror,the removal function of an elastic ball tool with deflected rotation motion was researched,and the relations between the max removal depth of removal function,dwell time and other parameters obtained by experiments were demonstrated.By using a 2-step method for polishing,it shows that when the ratio of rotating angle velocity to tool-workpiece is 1.41,the surface quality is in the best state.Furthermore,the fabrication of Wolter-Ⅰ grazing mirror base on Computer Control Optical Surface(CCOS) was introduced.In the research,Zerodur glass was selected as mirror substrates and it was polished by CeO abrasive on a Digital Control(NC) platform developed by ourselves.By changing the distance between the tool and the workpiece,the removal functions in different contact areas were determined in the experiments,and the residual error from previous polishing process was corrected effectively.Using two kinds of measurement devices to outline the surface profile,it shows that the final surface figure of the mirror is 1.39 μm(PV),0.34 μm(RMS) and the error of circularity is less than 0.1 μm(RMS).These results demonstrate the feasibility of fabricating Wolter-Ⅰ grazing mirror with the 2-step deflected rotation method.

Three types of LC materials with isothiocyanate tolane group were prepared via couple and electronation reaction.These LCs exhibit a high birefringence,and the Δn increased with conjugation length of π-electron,the maximal value among these LCs was 0.576.When these LCs were mixed in the commercial alkyne LCs respectively,the response performance of the device could be improved.These data demonstrates that the isothiocyanate tolane LCs have high Δn and low rotational viscosity,which can be used in the device of LC spatial modulator.

A novel technology for fabricating WolterⅠgrazing mirrors by an elastic ball tool was described in this paper.According to the Hertz contacting theory and Preston equation,a removal function model for tool movement on a cylinder surface was established based on the precession motion.The comparison of the theoretica1 model and the experimental results shows that the RMS distance warp between the theoretica1 removal function curve and the experimental curve is 0.101 22 μm,and its deflection ratio is 9.8%.Furthermore,the effect of different precession angles on the removal function was validated,which points out that the larger the precession angle is,the more the material are removed and the max removal point moves to the centre of contact area closely.With different precession angles,the rms deviation of max removal depth is 0.201 μm and the rms position deviation of max removal depth is 0.255 mm.The experimental results verify the feasibility of the theoretica1 model of removel function.The model can direct the fabrication of WolterⅠgrazing mirrors and can realize the deterministic material removal.