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浏览/检索结果: 共7条，第1-7条 帮助 限定条件 发表日期：2009     已选(0)清除 条数/页：5101520253035404550556065707580859095100   排序方式：请选择作者升序作者降序题名升序题名降序发表日期升序发表日期降序提交时间升序提交时间降序 Rigorous vector analysis of diffractive microlens by using of finitedifference time-domain method (EI CONFERENCE) 会议论文 2009 International Conference on Optical Instruments and Technology, OIT 2009, October 19, 2009 - October 22, 2009, Shanghai, China Liu Y.; Liu H. 收藏  |  浏览/下载：21/0  |  提交时间：2013/03/25 We use finite difference time domain (FDFD) method as rigorous vector analysis model to simulate the focusing process of diffractive microlens (DML). Differing with most analysis model which the near field distributions are calculated by FDTD and then far field are obtained by using of propagation method  we obtain the fields in whole computational space by using of FDTD only. The advantages are that all the results are vector based and the computational time is saved greatly. In this paper  we present two methods to obtain wave amplitude  one is comparison method  and the other is integral method. Depending on wave amplitude in the whole computational space  one can conveniently obtain distributions of electric field intensity and calculate the time-average Poynting vector. We also present the formulation for calculating diffractive efficiency of DML based on time-average Poynting vector which denotes energy flow. As demonstration  a DML is analyzed by using of these algorithms. The time depended graphic results of FDTD show the process of wave propagation. The distribution of electric field intensity illustrates the focusing of the normal incident light. The focus pattern in the focal plane is also show. The diffractive efficiency of the DML is calculated by using of the energy flow method in this paper. The results show the high accuracy and efficiency of the model. 2009 SPIE.   Novel method for optimizing polishing tool-path in CCOS based on weighted-iterative algorithm (EI CONFERENCE) 会议论文 4th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Advanced Optical Manufacturing Technologies, November 19, 2008 - November 21, 2008, Chengdu, China Deng W.-J.; Zhang X.-J.; Wang X.-K.; Wang X. 收藏  |  浏览/下载：31/0  |  提交时间：2013/03/25 In Computer Controlled Optical Surfacing (CCOS)  polishing tool-path is the base of solving other control parameters such as dwell time. In order to improve the fabrication results of polishing off-axis aspheric  a novel method to optimize the tool-path is discussed in this paper. The optimizing method named weighted-iterative algorithm is according to the balance principle of the particle system. The power factor of each dwell point represents the requirement of dwell density. Considering the factors which influence the polishing result  the power factors cosist of three elements include constant  error distribution and dwell distance of workpiece edge. The tool-path is solved by numerical iterative method. In the end  an error data is simulated with actual parameters using the matrix-based algorithm with two different tool-paths. The one is X-Y uniform spacing model and the other one is to optimize it based on the first. The comparison shows that the results of the optimized one are much better than traditional one  especially the rms convergence rate. Theory of the algorithm is simple and exercisable  and it satisfies practical requirement as well. 2009 SPIE.   Test of an off-axis asphere by subaperture stitching interferometry (EI CONFERENCE) 会议论文 4th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment, November 19, 2008 - November 21, 2008, Chengdu, China Wang X.-K.; Zheng L.-G.; Zhang B.-Z.; Li R.-G.; Di F.; Deng W.-J.; Xu W.; Feng Z.; Zhang Z.-Y.; Zhang X.-J. 收藏  |  浏览/下载：45/0  |  提交时间：2013/03/25 A new method combined subaperture stitching with interferometry(SSI) is introduced. It can test large and off-axis aspheric surfaces without the aid of other null optics. In this paper the basic principle and theory of the technique are analyzed. The synthetical optimization stitching model and effective stitching algorithm are established based on homogeneous coordinates transformation and simultaneous least-squares method. The software of SSI is devised and the prototype for testing of large aspheres by SSI is designed and developed. An off-axis asphere with the aperture of 376mm188mm is tested by this method. For comparison and validation  and the difference of PV and RMS error between them is 0.047 e and 0.006 e  the asphere is also tested by null compensation.The synthesized surface profile is consistent to that ofthe entire surface from null test  respectively. So it provides another quantitative measurement for testing large aspheric surfaces and off-axis aspheres besides null-compensation. 2009 SPIE.   Double-swing method used for polishing off-axis aspherical mirrors (EI CONFERENCE) 会议论文 4th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Advanced Optical Manufacturing Technologies, November 19, 2008 - November 21, 2008, Chengdu, China Wang P.; Li J.-F.; Xuan B.; Chen X.-P.; Song S.-M.; Chen Y.; Xie J.-J. 收藏  |  浏览/下载：28/0  |  提交时间：2013/03/25 Based on the characteristics of off-axis aspherical surface  the comparison of simulation effects under different parameters is made. In order to achieve optimal parameters  a new method used for polishing off-axis aspherical mirrors-Double-Swing Method (DSM) is proposed in this paper  a high order off-axis rectangle aspherical mirror has been polished by DSM. The final result of profile measurements of 12nm  and the polishing mechanism of DSM is introduced. The mathematical model of the DSM with steady movement state is established.The movement of this mathematical model is simulated in a programming language  RMS is achieved. The result indicates that the method is of practice and has even higher working efficiency and precision. 2009 SPIE.   Performance comparison of particle Swarm optimization and genetic algorithm in rolling fin-tube heat exchanger optimization design 会议论文 作者:  Han, Wutao;  Tang, Linghong;  Xie, Gongnan;  Wang, Qiuwang 收藏  |  浏览/下载：1/0  |  提交时间：2019/12/18 Design parameters  Fin-tube heat exchangers  Optimization design  Optimization method  Optimization objective function  Optimization variables  Performance comparison  Restrictive conditions   On quenching for some parabolic problems 期刊论文 Nonlinear Analysis, Theory, Methods and Applications, 2009, 卷号: 71, 期号: 7-8, 页码: 2416-2430 作者:  Zheng, Gao-Feng* 收藏  |  浏览/下载：1/0  |  提交时间：2019/12/23 Parabolic problems  Quenching  Sturm-Liouville comparison  The method of moving planes   Mittag-Leffler stability of fractional order nonlinear dynamic systems 期刊论文 Automatica, 2009, 卷号: 45, 期号: 8, 页码: 1965-1969 作者:  Yan Li;  YangQuan Chen;  Igor Podlubny 收藏  |  浏览/下载：1/0  |  提交时间：2019/12/26 Fractional order dynamic system  Nonautonomous system  Fractional Lyapunov direct method  Mittag-Leffler stability  Fractional comparison principle