The position and size of the monochromator , focusing curvature radii and tilting angles of the germanium focusing monochromator under different different take - off angle , size and divergency of the second collimator and intensity loss due to the use of it were determined . the neutron flux at different wavelength , under different reflection and take - off angle of the monochromator and divergency of the first collimator , were given . the simulation on the aperture used for limiting beam size in front of the sample showed that , smaller the size of the aperture and further the distance from the aperture to the sample , greater the loss of the intensity and more serious the spread of the beam along vertical direction at the sample position which makes the practical sampling volume greater than expected 用蒙特卡罗模拟方法对中子应力衍射谱仪的设计方案进行了优化研究，提出了一系列可供参考的数据：确定了单色器的位置、尺寸、垂直聚焦单色器在不同起飞角下的聚焦曲率半径和倾角；讨论了第二准直器的尺寸和发散，以及使用第二准直器造成的强度损失；给出了在不同单色器反射面、起飞角、中子波长和第一准直器发散度的情况下样品处的中子注量率，以及多种组合情况下谱仪的分辨率曲线；对限束方孔的尺寸、距离样品远近对强度损失和测量中的影响做了深入研究。
According to the theoretical model of light transmission in the grin medium , theoretically demonstrate the feasibility of the novel couimator via the theoretical computation of the collimation of the maxwell fisheye lens and the micro - sphere lens we made . chapter 5 . introduce the fabrication process of polymer grin micro - sphere couimator and analyze its effect of collimation 第五章介绍分别用玻璃和聚合物均匀折射率微球透镜，以及我们自制的安徽大学硕士毕业论文摘要聚合物grin微球透镜制作光纤准直器的研制过程，并对其准直性能测量结果进行了比较和分析。
On the basis of that , systematical theoretical analysis was made on the collimation effects of the homogenous medium micro - sphere lens and the grin micro - sphere - lens , which has demonstrated the feasibility of producing better fiber collimator with grin micro - sphere lens . from that many valuable technical parameters were obtained . at the same time , we fabricated a few of fiber collimators using homogenous glass micro - sphere lenses and grin micro - sphere - lenses respectively , ( for short : s - lens collimator ) and we find the results of the experiment and theoretical computation are coherent 在此基础上，对用各种不同参数的均匀介质微球透镜和grin微球透镜制作光纤耦合准直器的性能进行了系统的理论分析，证明用grin微球透镜可以制备性能更为优越的光纤准直器，并获得一批具有参考价值的技术参数；同时，我们分别用玻璃均匀折射率微球透镜，以及我们自制的聚合物grin微球透镜制作了一批光纤准直器(可简称为s -透镜准直器) ，实验结果与理论计算的结果一致。
Moreover , compensated for aberration of ball lens by designing phase compensating plate to get a higher energy utilization rate . third , combining with the light beam property of dwdm system , put forward taking fresnel lens array as fiber arrayed collimator , designed differently structured lens array and discovered the arrayed collimator loss property , which compared with the existing parameter of fiber collimator , embodies many advantages as arrayed collimator 结合密集波分复用系统的光束耦合特点，提出用菲涅尔透镜列阵做光纤阵列准直器，并设计不同结构的透镜列阵，得出了该阵列准直器的光束耦合损耗特征，与现有的光纤准直器的参数相比，体现出用菲涅尔透镜列阵作阵列光纤准直器的诸多优势。
The object of single photon emission computed tomography ( spect ) is to reconstruct an unknown radioactivity distribution inside the body from projection data consisting of the number of photon collected on a collimated gamma camera . these projections are not simple line integrals but have point - spreads due to the imperfect collimator of the detector and attenuation due to the compton scattering . so 这种投影数据与透射ct中的数据不同，由于存在着光子的点扩散(由准直器引起)和衰减(由散射引起) ，已经不能用简单的线积分来描述这个问题，因此相对于透射ct而言，这个领域将面临很多困难。
