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11.
二元光学分束器的设计   总被引:2,自引:0,他引:2  
系统地阐述了几种二元光学分束器的基本设计理论,比较其算法以及衍射效率和再现误差,并提供了设计实例。  相似文献   
12.
大功率半导体激光器全固态风冷散热系统   总被引:1,自引:0,他引:1  
张云鹏  套格套  尧舜  陈平  王立军 《光电工程》2004,31(Z1):114-116
设计并制作了一种全固态大功率半导体激光阵列恒温散热系统。它利用半导体制冷器对大功率半导体激光阵列吸热,然后经由风冷散热。经测试,单bar激光阵列连续输出功率达到15.28W,双 bar 阵列输出达 27.8W 时,全部达到风冷散热控温精度±0.1 ;当环境温度达到 45 时,仍然能够保证激光阵列的正常使用。  相似文献   
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LDA抽运Nd:YLF再生放大器的实验研究   总被引:3,自引:2,他引:1  
研制了一台激光二极管列阵(LDA)抽运的Nd:YLF再生放大器。再生放大器工作波长1053 nm,重复频率1 Hz,输出4 ns宽基横模TEM00激光脉冲的能量为2 mJ。总放大倍数达到了1×10 7,输出能量稳定性优于±4.7%(峰值)。给出了再生放大器的实验装置和有关实验结果。  相似文献   
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Summary A derivation of a parallel algorithm for rank order filtering is presented. Both derivation and result differ from earlier designs: the derivations are less complicated and the result allows a number of different implementations. The same derivation is used to design a collection of priority queues. Both filters and priority queues are highly efficient: they have constant response time and small latency. Anne Kaldewaij received an M.Sc. degree in Mathematics from the University of Utrecht (The Netherlands) and a Ph.D. degree in Computing Science from the Eindhoven University of Technology. Currently, he is associate professor in Computing Science at Eindhoven University. His research includes parallel programming and the design of algorithms and data structures. He enjoys teaching and he has written a number of textbooks on mathematics and programming. Jan Tijmen Udding received an M.Sc. degree in Mathematics in 1980 and a Ph.D. degree in Computing Science in 1984 from Eindhoven University of Technology. Currently, he is associate professor at Groningen University. His main research interests are mathematical aspects of VLSI, program derivation and correctness, and functional programming.  相似文献   
15.
纳米碳管阵列   总被引:8,自引:0,他引:8  
在概括纳米碳管阵列特异的场发射效应及在场发射器方面应用前景的基础上,介绍了合成纳米碳管阵列的研究历程以及化学气相沉积法在纳米碳管阵列合成方面的重要意义,就当前纳米碳管阵列的快速合成与低温合成两个发展方向进行了概述,并指出等离子体化学气相沉积法能有效地用于纳米碳管阵列的低温合成。  相似文献   
16.
We developed a process to obtain sharper silicon tips by employing anisotropic etching in a KOH solution followed by SF6 plasma etch. The tips were further sharpened using the established thermal oxidation technique to decrease the cone angle and, therefore, obtain smaller curvature radii. We have analyzed the impact of such changes in geometry on a figure of merit associated with the field emission characteristics. An increase in the figure of merit by a factor of three was found in relation to the tips before sharpening.  相似文献   
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A new approach is presented for easily testable two-dimensional iterative arrays.It is an improvement of GI-testability (Group Identical testability)and is referred to as GID-testability (Group Identical and Different testability).In a GID-testable two-dimensional array,the primary x and y outputs are organized into groups and every group has more than one output.This is similar to the GI-testable arrays.However,GID-testability not only ensures that identical test responses can be obtained from every output in the same group when an array is fault free,but also ensures that at least one output has different test responses (from the other outputs in a group)when a cell in the array is faulty.Therefore,all faults can be detected under the assumption of a single faulty cell model.It is proved that an arbitrary two-dimensional iterative array is GID-testable if seven x-states and seven y-states are added to the original flow table of the basic cell of the array.GID-testability simplifies the response verification of built-in-self-testing in a way similar to PI-and GI-testability^[6-9].Therefore,it is suitable for BIST design.  相似文献   
19.
An algorithm for reconstructing a binary array of size N sx N from its forest of quadtree representation is presented. The algorithm traverses each tree of the forest in preorder and maps each ‘black’ node into the spatial domain. The time complexity in mapping is O(log N × Bn + Bp), where Bn is the number of black nodes in the forest and Bp is the number of black pixels in the N × N array. The algorithm has been implemented on an Apple II.  相似文献   
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