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51.
Fangfang Luo Geng Lin Haiyi Sun Li Liu Qingxi Chen Jianrong Qiu Zhizhan Xu 《Optics Communications》2011,284(19):4592-4595
Permanent microscale bubbles with varied size and number density are induced in borosilicate glasses by adjusting the focusing depth (FD) of a tightly focused femtosecond laser. With continuously increasing of the focusing depth, the average size of generated bubbles experiences an increase-decrease process. However, the number density of generated bubbles experiences an opposite changing process compared to the change of the size. The possible mechanism for the bubble generation and changing with the focusing depth has been discussed. 相似文献
52.
We analyze the orbital angular momentum (OAM) crosstalk of single photons propagation through low-order atmospheric turbulence. The probability models of the orbital angular momentum crosstalk for single photons propagation in the channel with the non-Kolmogorov turbulence tilt, coma, and astigmatism and defocus aberration have been established. It is found, for α = 11/3, that the turbulent tilt is the dominant aberration which causes the orbital angular momentum crosstalk, the coma is second and the astigmatism is third, but the defocus aberration has no impact on OAM. The results also indicate that the regularities of orbital angular momentum crosstalk caused by the tilt, the coma and the astigmatism are almost the same, respectively. The crosstalk probability of the orbital angular momentum increases as the azimuth mode index p of Laguerre-Gaussian (LG) beam increases, the turbulent strength Cn2 enhances, the orbital angular momentum quantum number rises, the diameter of circular sampling aperture D and the channel zenith angle θ increase. 相似文献
53.
Guiyan Zhao 《Optik》2011,122(1):29-32
The effect of tilt and astigmatism aberration of the turbulent atmosphere on the intensity distribution of a focused vortex carrying Gaussian beam was investigated based on the extended Fresnel-Kirchhoff diffraction integral and the quadratic approximation of phase structure function. Our results have shown that the intensity distribution on the focal plane in the effect of tilt aberration changes with the turbulent strength, the propagation distance and the topological charge of the initial beam. The propagation distance is larger, the focal spot size will be larger, and the central dip will be less deep. It is also noticed that the intensity distribution of a beam with single topological charge is affected more by tilt aberration in comparison to the beam with double topological charge. The effect of astigmatism on the intensity distribution is quite less than that of tilt aberration. For focused beam propagation in atmosphere, the effect of the tilt aberration on the intensity distribution of optical vortex beam is the main effect of total turbulent aberration. 相似文献
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提出了一种新的适用于移变降质图像复原的算法——能量约束自适应迭代复原.算法采用能量约束复原的空域迭代形式,使其能够用于处理光学像差引起的移变降质复原问题;以局部能量约束取代总体能量约束,使算法具有空间自适应特性;并采用双通道处理方法,消除能量约束带来的图像亮度衰减,同时抑制图像边界截断引起的振荡波纹.场曲复原仿真实验结... 相似文献
56.
瑞奇-康芒法是大口径平面元件面形检测的有效方法.通过分析检测光瞳到被检平面的位置转换关系以及波像差到面形误差的幅值转换关系,分别对检测得到的波像差以及干涉仪离焦产生的Power进行转换处理,利用最小二乘法计算出瑞奇-康芒两角度检测时的干涉仪离焦量,从而获得被检平面的面形误差分布.实验部分给出了第4项到第37项泽尼克多项... 相似文献
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本文利用GS方法对COIL谐 振腔调控光的波前进行了测量。并利用Zernik多项式对其进行了像差分析,给出了波前误差的均方根值。 相似文献
60.
J. P. Wesley 《Foundations of Physics Letters》1990,3(4):395-397
Because terrestrial sources radiate in all directions, collimation cannot produce a beam fixed in direction relative to absolute space. Therefore, terrestrial aberration, even though present, cannot be observed; and terrestrial aberration cannot be used to measure the absolute velocity of the closed laboratory (contradicting a prior claim in this journal). In other words, the large parallax of terrestrial sources frustrates the observation of aberration. 相似文献