Study of the Laser Light Effect on Improving Sheep Semen Quality

ＳｔｕｄｙｏｆｔｈｅＬａｓｅｒＬｉｇｈｔＥｆｆｅｃｔｏｎＩｍｐｒｏｖｉｎｇＳｈｅｅｐＳｅｍｅｎＱｕａｌｉｔｙ￥ＹＵＥＷｅｎｂｉｎ；ＬＩＵＷｅｎｚｈｏｎｇ（ＤｅｐａｒｔｍｅｎｔｏｆＡｎｉｍａｌＳｈａｎｘｉＡｇｒｉｃｕｌｔｕｔａｌＵｎｉｖｅｒｓｉｔｙ，Ｓ...     

The Hardness Properties of Carbon Steels After Laser Processing

ＴｈｅＨａｒｄｎｅｓｓＰｒｏｐｅｒｔｉｅｓｏｆＣａｒｂｏｎＳｔｅｅｌｓＡｆｔｅｒＬａｓｅｒＰｒｏｃｅｓｓｉｎｇ￥ＺＨＵＺｕｃｈａｎｇ；ＷＡＮＧＷｅｉｘｉａｎｇ；ＬＩＸｉｕｑｉａｎ；ＹＵＳｈａｏｌｕｏ（ＳｈａｎｇｈａｉＵｎｉｖｅｒｓｉｔｙｏｆＥｎｇｉｎ...     

Effects of He－Ne laser irradiation at acupuncture points on steroid hormone receptors of uteri in rabbits

ＥｆｆｅｃｔｓｏｆＨｅ－Ｎｅｌａｓｅｒｉｒｒａｄｉａｔｉｏｎａｔａｃｕｐｕｎｃｔｕｒｅｐｏｉｎｔｓｏｎｓｔｅｒｏｉｄｈｏｒｍｏｎｅｒｅｃｅｐｔｏｒｓｏｆｕｔｅｒｉｉｎｒａｂｂｉｔｓ￥ＨＵＡＮＧＰｉｎｇ；ＣＡＩＳｈａｎｇｄａ；ＱＩＵＹｉｇｕａｎｇ；ＨＵ...     

Nonlinear Evolution of Driven Electron Plasma Oscillations in Inhomogeneous Plasmas

ＮｏｎｌｉｎｅａｒＥｖｏｌｕｔｉｏｎｏｆＤｒｉｖｅｎＥｌｅｃｔｒｏｎＰｌａｓｍａＯｓｃｉｌｌａｔｉｏｎｓｉｎＩｎｈｏｍｏｇｅｎｅｏｕｓＰｌａｓｍａｓ￥ＳＨＥＮＧＺｈｅｎｇｍｉｎｇ；ＸＵＺｈｉｚｈａｎ；ＹＵＷｅｉ；ＭＡＪｉｎｘｉｕ（ＳｈａｎｇｈａｉＩｎ...     

Studying the Mode－Spectra Characteristics of An Above－Threshold Biased Semiconductor Laser

ＳｔｕｄｙｉｎｇｔｈｅＭｏｄｅ－ＳｐｅｃｔｒａＣｈａｒａｃｔｅｒｉｓｔｉｃｓｏｆＡｎＡｂｏｖｅ－ＴｈｒｅｓｈｏｌｄＢｉａｓｅｄＳｅｍｉｃｏｎｄｕｃｔｏｒＬａｓｅｒ￥ＸＩＡＧｕａｎｇｑｉｏｎｇ；ＷＵＺｈｅｎｇｍａｏ；ＣＨＥＮＪｉａｎｇｕｏ；ＬＵＹｕｃｕ...     

Suppression of Interference Speckles in the Uniform Line Focus System of Segmented Wedge Array Using Phase－disturbed Plate

ＳｕｐｐｒｅｓｓｉｏｎｏｆＩｎｔｅｒｆｅｒｅｎｃｅＳｐｅｃｋｌｅｓｉｎｔｈｅＵｎｉｆｏｒｍＬｉｎｅＦｏｃｕｓＳｙｓｔｅｍｏｆＳｅｇｍｅｎｔｅｄＷｅｄｇｅＡｒｒａｙＵｓｉｎｇＰｈａｓｅ－ｄｉｓｔｕｒｂｅｄＰｌａｔｅ￥ＬＩＵＺｈｏｎｇｙｏｎｇ；ＺＨＥＮＧ...     

The Optimization of the PDA Optical System

ＴｈｅＯｐｔｉｍｉｚａｔｉｏｎｏｆｔｈｅＰＤＡＯｐｔｉｃａｌＳｙｓｔｅｍ￥ＨＯＵＱｉｎｇｗｅｎ；ＺＥＮＧＺｈｏｕｍｏ；ＳＵＮＪｉａｚｉ；ＹＡＮＧＸｕｅｙｏｕ（Ｄｅｐｔ．ｏｆＰｒｅｃｉｓｉｏｎＩｎｓｔｒｕｍｅｎｔＥｎｇｉｎｅｅｒｉｎｇ，ＴｉａｎｊｉｎＵ...     

Electric Field Analysis of Non－coplanar Electrodes in Electrooptic Modulator with a Ridge Waveguide Structure

ＥｌｅｃｔｒｉｃＦｉｅｌｄＡｎａｌｙｓｉｓｏｆＮｏｎ－ｃｏｐｌａｎａｒＥｌｅｃｔｒｏｄｅｓｉｎＥｌｅｃｔｒｏｏｐｔｉｃＭｏｄｕｌａｔｏｒｗｉｔｈａＲｉｄｇｅＷａｖｅｇｕｉｄｅＳｔｒｕｃｔｕｒｅ￥ＺＨＯＵＹｉ；ＹＵＹａｎｇ；ＱＩＵＷｅｉ；ＣＨＥＮＹｉｘ...     

Studies on the Plasma Shielding of 1.06μm Laser on the Aluminum Target

ＳｔｕｄｉｅｓｏｎｔｈｅＰｌａｓｍａＳｈｉｅｌｄｉｎｇｏｆ１．０６μｍＬａｓｅｒｏｎｔｈｅＡｌｕｍｉｎｕｍＴａｒｇｅｔＬＵＪｉａｎ；ＮＩＸｉａｏｗｕ；ＨＥＡｎｚｈｉ（ＤｅｐａｒｔｍｅｎｔｏｆＡｐｐｌｉｅｄＰｈｙｓｉｃｓ，ＮａｎｊｉｎｇｏｆＳｃｉｅｎｃ...     

Some Problems on Reconstruction of Soft X -ray Hologram with Visible Light

ＳｏｍｅＰｒｏｂｌｅｍｓｏｎＲｅｃｏｎｓｔｒｕｃｔｉｏｎｏｆＳｏｆｔＸ－ｒａｙＨｏｌｏｇｒａｍｗｉｔｈＶｉｓｉｂｌｅＬｉｇｈｔ￥ＣＨＥＮＪｉａｎｗｅｎ；ＸＵＺｈｉｚｈａｎ；ＺＨＵＰｅｉｐｉｎｇ；ＸＩＡＯＴｉｑｉａｏ；ＫＯＵＬｅｉｇａｎｇ；ＷＡＮＧＺｈ...     

掺铒光纤激光器输出特性的解析研究

从描述掺铒光纤激光器的速率方程组出发，对９８０ｎｍ和１４８０ｎｍ波段泵浦下掺铒光纤激光器的输出特性进行了解析研究，得到了这两个波段泵浦下下输出功率，斜效率等重要参烽的隐式或显示解析表达式。     

Theoretical analysis of multimode fiber amplifiers and lasers containing spatial filters

By the use of the coupling theory of the modes and the multimode rate equations, the performances of the multimode fiber amplifiers or lasers containing a spatial filter have been discussed. After the rate equations applicable to amplifiers are solved, the beam quality factors of the output from a multimode fiber amplifier with and without a single mode filter have been evaluated and compared. By the use of the analytical expression of the threshold pump power applicable to the multimode fiber lasers with the spatial filter and doped with quasi two-energy-level ions, and two example fibers had been selected which may guide 4 and 9 transversal modes, respectively, the threshold pump power for each transversal fiber mode has been evaluated. The results indicate that the single mode filter, does introduce a very strong discrimination for the modes between the high order modes and the fundamental mode. This should considerably favor the operation of the fundamental mode in the lasers with a homogeneously broadened active medium.     

Theory of tunable FIR laser

Tunable properties of optically pumped FIR lasers have been studied on the basis of sixlevel quantum system approach. The signal flow graph method was used to solve the density matrix equations. A set of tuning characteristic curves has been obtained in good agreement with the experimental results for optically pumped HF FIR lasers given by A. de Martino et al.     

Analytical solutions to rate equations including losses describing threshold pumped fiber lasers

An exact analytical expression to the threshold pump power has been deduced for rate equations including loss coefficients applicable to fiber lasers doped with quasi two-energy-level ions. Following the derivation of a closed-form expression for the variation of the pump power along the fiber, together with analytical solutions to the position dependent atom population density and laser power in terms of the pump power, we have analytically and fully solved rate equations describing threshold pumped fiber lasers. A comparison has also been made between the exact analytical result with the previous reported results, which indicates that various approximation have underestimated the threshold pump powers.     

Rate equations studies on coherently combined fiber lasers connected by an optical coupler

Attempt has been made to apply the steady-state rate equations to study two coherently combined Er³⁺-doped fiber lasers joined by an optical fiber coupler. In order to establish the boundary conditions, which are necessary for solving the equations, we have taken into consideration the fact that a constructive interference at the coupler assures that the laser radiations from both constituent lasers are directed to the coupler output port to which a reflection mirror defining both lasers is attached. Consequently, effective reflectivity, provided by the coupler-mirror combination, can be specified in terms of the laser powers of both laser signals, and the rate equations describing the compound system can be solved. Using the derived solutions, quantitative investigations can be made on the influences of different laser parameters. For example, the influence of the length difference between doped fibers, the splitting ratio of the coupler and power difference between the two pump radiations have been given in this report.     

光调制技术测量半导体激光器固有高频响应

采用一种新的全光纤连接的半导体激光器光调制技术,实现了对高速半导体激光器同有响应的直接测量。利用速率方程能够对光调制的动态响应过程进行准确的描述。基于对抽运源和探测器的频率响应对光调制数据准确性影响的分析．通过将网络分析仪校正到同轴端．然后用直接扣除法和相互扣除法,在网络分析仪外部对测量数据进行了修正。两种修正方法得到了一致的结果．并且同已有的理论和实验结果相符合。改进后的光调制技术和两种修正数据的方法不但提高了数据的精确性,而且扩展了测量的频率范围。     

Modeling of Q-switched lasers with top-hat pump beam distribution

For laser diode end-pumped solid-state lasers, the pump beam can be considered to be a Gaussian distribution or a top-hat distribution or between them. The rate equations for Q-switched lasers have been treated before, by considering the pump beam as a Gaussian distribution. This paper deals with the rate equations and the solutions for Q-switched lasers under a top-hat pump beam distribution. The normalized rate equation is obtained and solved numerically. A group of general curves are given and the comparison with the results under the Gaussian pump beam distribution and the plane-wave approximation is made. The results show that the solutions of the rate equations under a top-hat pump beam distribution are different from those under a Gaussian pump beam distribution, but the difference is very small. The solutions of the rate equations under both situations can give much more precise theoretical results than those under the plane-wave approximation. PACS 42.60.Gd; 42.55.Xi; 42.55.Ah     

三能级光纤激光器速率方程组的阈值解析解

 在考虑了泵浦损耗及激光损耗的情况下，解析求解了阈值泵浦下的三能级光纤激光器速率方程组，获得了泵浦功率阈值的显函数解析表达式，泵浦功率沿光纤变化的隐函数表达式，以及用功率变化表示的各个能级的粒子数密度随位置变化的显函数表达式。并利用这些表达式对光纤激光器的阈值特性进行了研究，研究表明：泵浦功率阈值随泵浦损耗系数增大而增大；激光上能级粒子数密度随归一化位置呈下降趋势，而下能级粒子数密度的变化与此相反；泵浦功率阈值越大(光纤长度越长),净增益系数随归一位置下降就越快。所获得的结果适用于单包层和双包层光纤激光器。     

Modelling of RF CO2 Laser Pulses

The usual laser rate equations have been applied to fit energy and shape of pulsed emissions of RF CO₂ single mode lasers starting from the discharge and cavity parameters. The model well reproduce the laser behaviour, if to fit the turn-off normally observed in these lasers we introduce a phase laser gain correction related to the frequency chirp.     

Temporal investigation of acoustic wave pressure spectrum of high repetition rate TEA-CO2 lasers by using a three-dimensional mathematical model

The production of acoustic wave is one of the most important factors on the action of High Repetition Rate TEA-CO₂ lasers. In this paper a three-dimensional mathematical modeling has been considered for investigation of temporal and spatial variations of acoustic waves in the laser cavity and its effect on the output of HRR lasers. By calculation of equations obtained from this model and plotting the pressure spectrum in different states, the effect of electrodes dimensions, cavity dimensions, gas flow velocity and repetition rate of laser in different times have been acquired. At last, optimum conditions for performance of laser action and having a good output have been arrived.