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111.
数字全息研究领域目前存在两种不同的数字全息图取样模型.按照这两种模型进行研究时, 不但涉及较复杂的数学运算, 在许多情况下还会导致不同的研究结果, 不便于理论分析及实际应用.基于对数字全息图记录的物理过程分析及电荷藕合器件(charge coupled device, CCD)几何结构的研究, 本文将这两种取样模型简化为相同的数学表达式. 利用数字全息图的余弦级数展开及取样定理对简化模型的研究表明, 简化模型不但具有清晰的物理意义, 而且可以方便地为应用研究服务. 基于简化模型对物光波通过光学系统到达CCD的数字全息记录系统进行了研究, 导出得到实验证实的波前重建表达式.
关键词:
数字全息
波前重建
相干光成像 相似文献
112.
113.
Dong Dao-yi Chen Zong-hai Zhang Chen-bin Chen Chun-lin 《Frontiers of Physics in China》2006,1(3):256-262
Feedback is a significant strategy for the control of quantum system. Information acquisition is the greatest difficulty in
quantum feedback applications. After discussing several basic methods for information acquisition, we review three kinds of
quantum feedback control strategies: quantum feedback control with measurement, coherent quantum feedback, and quantum feedback
control based on cloning and recognition. The first feedback strategy can effectively acquire information, but it destroys
the coherence in feedback loop. On the contrary, coherent quantum feedback does not destroy the coherence, but the capability
of information acquisition is limited. However, the third feedback scheme gives a compromise between information acquisition
and measurement disturbance. 相似文献
114.
光束的空间相干性与空间质量评价 总被引:3,自引:2,他引:1
光束空间质量评价的标准应该能够反映光束的空间相干性和强度(功率或能量)分布,并主要由空间相干性的优劣来说明.本文对模式纯度(1-δ)以及空间质量评价因子-衍射极限倍数因子M2做了讨论,并对此因子的表达形式提出了我们的改进建议. 相似文献
115.
本文利用金量子理论得到了与双模量子光场作用的Raman型原子的稳态光电子谱的一般表达式,考察了驱动光场的光子数分布对原子稳态光电子谱的影响,分析了原子相干捕获性质对光场两模光子间相关性质的依赖,论证了产生梳状相干凝集现象的条件. 相似文献
116.
N. Mazars 《商业与工业应用随机模型》1989,5(3):203-231
Binary coherent system theory has played an important part in reliability. Its extension to (‘degradable’ or ‘multistate’ or) multinary systems has recently been considered in various papers, through various definitions. This paper studies the most general model for multinary systems, proposes a unified viewpoint on multinary coherent systems and gives unified arguments to apply and to investigate further the binary and multinary cases. In a more detailed way, the ‘helpful bridge’ lately proposed by Block and Savits1 between the binary and multinary cases is completed and multinary systems then can be studied in terms of monotone binary coherent systems, introduced in a companion paper.2 Through various results, multinary systems are examined in terms of structure functions and of life functions; fundamental relations for their analysis are obtained with their set characterizations; the main axis that can be retained among the numerous types of coherence is emphasized, in a unified way, through relevance; reliability models are examined through performance processes, life lengths and performance functions; and Birnbaum's factors of importance are thoroughly extended to the multinary case. Fundamental results proposed in previous studies are thus completed with a shorter unified approach. 相似文献
117.
118.
Roy J Glauber 《Chemphyschem》2006,7(8):1618-1639
119.
A. A. Lichmanov Ch. M. Briskina V. M. Markushev V. N. Lichmanova N. P. Soshchin 《Journal of Applied Spectroscopy》1998,65(5):818-825
A degree of coherence of powder-laser radiation of 10–20% is estimated by the magnitude of the image contrast for a speckle,
although cases are recorded where it attains 40–50%. It is found that as the average speckle intensity increases, the contrast
decreases. It is established that the minimum, dimensions of the generation region in powders are 20–30 μm. Cases of existence
of several generation centers simultaneously are noted. An attempt to interpret the results obtained is made.
Institute of Radio Engineering and Electronics, Russian Academy of Sciences, 11, Mokhovaya St., Moscow, 103907. Translated
from Zhurnal Prikladnoi Spektroskopii, Vol. 65, No. 5, pp. 780–786, September–October, 1998. 相似文献
120.
The analytic design of anamorphic optical system for transforming the coherent Gaussian beam of a He–Ne laser to a partially coherent Gaussian Schell-model beam with an anisotropic cross-section and an anisotropic degree of coherence is described. Design equations are formulated and some design examples are presented. 相似文献