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	Incoherent space beam combining of fiber-transmitted semiconductor lasers for oil well laser perforation 期刊论文 OAI收割 IEEE Access, 2019, 卷号: 7, 页码: 154457-154465 作者: Bai, Yang; Lei, Guangzhi; Chen, Haowei; Feng, Xiaoqiang; Li, Diao \| 收藏 \| 浏览/下载：58/0 \| 提交时间：2020/03/02 Fiber-transmitted incoherent space beam combining laser perforation overlapping ef ciency 10 kW
	Far-field focusing of laser beam based on digital image processing techniques (EI CONFERENCE) 会议论文 OAI收割 Optoelectronic Imaging and Multimedia Technology, October 18, 2010 - October 20, 2010, Beijing, China 作者: Zhao S.; Tian Y.-Z.; Liu L.-S.; Guo J.; Zhang H.-Y. 收藏 \| 浏览/下载：30/0 \| 提交时间：2013/03/25 In order to lead the laser beam transmit in the atmosphere convergently an experiment of laser focus at the distance of 450m and 300m has been operated in the outdoor place. The actual manipulations are as follows: Firstly the laser was collimated by a beam expander then the near-parallel laser beam was transmitted with a Galileo telescope system and the distance between the concave lens and the convex lens can be tuned through a precise displacement platform so the focus of the system changed due to the tiny displacement of the concave lens. Secondly the average power of the laser spot can be measured using power meter the power is 47.67mW and the standard deviation is 0.67mW while the focal length is 450m. Thirdly the energy distribution was found through the laser beam analyzer. The spot images were saved using the beam analyzer then the saved image can be processed with Matlab software afterwards. The function named EDGE and Sobel operator was used in the pre-processing of the saved image then method of median filter was used in the course of image de-noising and 53H filter was adopted in the signal analysis. The diameter of laser spot was obtained by the method above the diameter is 5.56mm and the standard deviation is 0.24mm. The spot center excursion is 0.56mm it is 10.43% of the total diameter of the laser spot. At last the key factors of the energy dissipation in the focusing system can be summarized as follows: restriction of the diffraction limit attenuation in the atmosphere geometrical aberration of optical system and the diffraction limit and the geometrical aberration are significant in the three factors above so we can reduce the impact of the both factors during the design of optical system. The reliable referenced data of the system design can be acquired through the primary experiment research. 2010 SPIE.
	Transverse shift of the transmitted beam of a non-uniformly polarized paraxial light beam at dielectric interfaces 期刊论文 OAI收割 chinese physics b, 2008, 卷号: 17, 期号: 10, 页码: 3720-3724 作者: Liu Bao-Ying; Li Chun-Fang 收藏 \| 浏览/下载：11/0 \| 提交时间：2011/09/30 transverse shift paraxial beam polarization transmitted beam
	Phase characteristics of laser beam in fibers (EI CONFERENCE) 会议论文 OAI收割 5th International Workshop on Adaptive Optics for Industry and Medicine, August 29, 2005 - September 1, 2005, Beijing, China 作者: Wang L.; Wang L.; Liu J.; Liu J.; Liu J. 收藏 \| 浏览/下载：38/0 \| 提交时间：2013/03/25 The phase changing rates1 of laser beam in single mode polarization maintaining fiber (PMF) Yb-doped rectangular inner cladding dual-clad fiber (DCF) and Yb-doped large-mode-area dual-clad fiber (LMF) are investigated by means of interference under situations with different exterior disturbance for situations that all the fibers are used as transmission medium only as well as amplifying medium with the last two. In this paper phase fluctuation characteristics of the beam transmitted through the fibers with no amplification are presented. The results show that the phase fluctuation frequencies of the laser beam transmitted through these three kinds of fibers are mainly in the range of 100-200Hz 100-300Hz and 80-400Hz respectively in normal laboratory environment. The phase fluctuation frequencies of the laser beam transmitted through the DCF in cases of when the environment temperature is changing a constant pressure is applied to the fiber and when vibration is applied are mainly in the range of 100-600Hz 100Hz-300Hz and 100-500Hz respectively. In the same cases for the LMF the phase fluctuation frequencies are mainly in the range of 150-600Hz 100-400Hz and 100-1000Hz respectively. It indicates that for realizing phase stabilization the bandwidth of any potential phase control2 system has to be in the range of a few kilohertz.