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Chinese Physics B 2011年第4期20卷 301-309页

作者：赵延仲孙华燕宋丰华 Department of Photoelectric Equivalent Academy of Equivalent Command and Technology

By using the extended Huygens-Fresnel diffraction integral and the method of expanding the aperture function into a finite sum of complex Caussian functions, an approximate analytical formula of the double-distance propagation for Caussian beam passing through a tilted cat-eye optical lens and going back along the entrance way in a turbulent atmosphere has been derived. Through numerical calculation, the effects of incidence angle, propagation distance, and structure constant on the propagation properties of a gaussian beam in a turbulent atmosphere are studied. It is found that the incidence angle creates an unsymmetrical average intensity distribution pattern, while the propagation distance and the structure constant can each create a smooth and symmetrical average intensity distribution pattern. The average intensity peak gradually deviates from the centre, and the central average intensity value decreases quickly with the increase in incidence angle, while a larger structure constant can bring the average intensity peak back to the centre.

关键词： cat-eye optical lens turbulent atmosphere gaussian beams double-distance propagation

Nonparaxial Dark-Hollow gaussian beams

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Chinese Physics Letters 2006年第1期23卷 106-109页

作者：高曾辉吕百达 Institute of Optoelectronic Information Yibin University Yibin 644000 Institute of Laser Physics and Chemistry Sichuan University Chengdu 610064

The concept of nonparaxial dark-hollow gaussian beams （DHGBs） is introduced. By using the Rayleigh-Sommerfeld diffraction integral, the analytical propagation equation of DHGBs in free space is derived. The on-axis intensity, far-field equation and, in particular, paraxial expressions are given and treated as special cases of our result. It is shown that the parameter f = 1/κω0 with κ being the wave number and ω0 being the waist width determines the nonparaxiality of DHGBs. However, the parameter range, within which the paraxial approach is valid, depends on the propagation distance. The beam order affects the beam profile and position of maximum on-axis intensity.

关键词： Nonparaxial Dark-Hollow gaussian beams

Sound Field Calculations of Elliptical Pistons by the Superposition of Two—Dimensional gaussian beams

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Chinese Physics Letters 2002年第12期19卷 1825-1827页

作者：张瑜刘金秋等 DepartmentofElectronicEngineering SoutheastUniversityNanjing210096

We present an alternative approach to calculate the sound field of ultrasonic transducers. The distribution function of sources is expanded into the superposition of a series of two-dimensional gaussian functions. The corresponding radiated sound field is expressed as the superposition of these two-dimensional gaussian beams and is then reduced to the computation of these simple functions. This treatment does not require the condition that the shape of the source is of circular axial symmetry. A numerical example is presented for the uniform elliptical piston transducer and this is in good agreement with the results given by complicated computation.

关键词： gaussian beams

Seismic interferometry and estimation of the Green's function using gaussian beams

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Earthquake Science 2010年第5期23卷 417-424页

作者： Robert L. Nowack Department of Earth and Atmospheric Sciences Purdue University

This study investigates seismic interferometry in which the Green＇s function is estimated between two receiv- ers by cross-correlation and integration over sources. For smoothly varying source strengths, the dominant contributions of the correlation integral come from the stationary phase directions in the forward and backward directions from the alignment of the two receivers. gaussian beams can be used to evaluate the correlation integral and concentrate the amplitudes in a vicinity of the stationary phase regions instead of completely relying on phase interference. Several numerical examples are shown to illustrate how this process works. The use of gaussian beams for the evaluation of the correlation integral results in stable estimates, and also provides physical insight into the estimation of the Green＇s function based on seismic interferometry.

关键词： seismic interferometry gaussian beams Green＇s function

Data regularization using gaussian beams decomposition and sparse norms

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Data regularization using Gaussian beams decomposition and s...

Quantitative deviation of the two-photon absorption coefficient based on three laser pulse models

中国科学院地质与地球物理研究所2013年度（第13届）...

作者： Yanfei Wang Peng Liu Zhenhua Li Tao Sun Changchun Yang Qingsheng Zheng Key Laboratory of Petroleum Resources Research Institute of Geology and GeophysicsChinese Academy of Sciences Center for Oil and Gas Resources Institute of Geology and GeophysicsChinese Academy of Sciences University of Chinese Academy of Sciences KeY Laboratory of Petroleum Resources Research.Institute of Geology and Geophysics Chinese Academy of Sciences

We consider seismic data regularization problems in this paper.gaussian beam decomposition model is proposed for seismic data representation.To solve the representation problem,an l quasi-norm minimization model with different smooth approximations is proposed.To solve the l quasi-norm minimization problem,a projected gradient method with nonmonotone choice of iterative steps is developed.Numerical simulations on one-dimensional and two-dimensional seismic imaging problems are performed to verify the feasibility of our methods.

关键词： Data regularization gaussian beams l0 optimization sparse inversion.

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Chinese Optics Letters 2010年第1期8卷 93-98页

作者：赵培德张勇包文霞张忠亚汪大云刘铭张志东 School of Science Hebei University of Technology

The pulse profile influence of excitation light on the two-photon absorption coefficient β is theoretically and numerically studied. Based on gaussian spatial and temporal laser, we obtain an expansion formula of energy transmission. As compared with a plain beam and a pulse beam that is rectangular in time but gaussian in space, the relative deviations of β turn out to be about 214% and 47%, respectively. These differences indicate that a smaller β may be obtained than the real one in usual nonlinear transmission. Our result suggests that by taking real pulse profile into account, a more exact β can be derived in energy transmission measurement.

关键词： Absorption gaussian beams Light absorption Luminescence of organic solids Multiphoton processes Optical materials Photons

Tolerance on tilt error for coherent combining of fiber lasers

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Chinese Optics Letters 2009年第1期7卷 39-42页

作者：周朴陈子伦王小林李霄刘泽金许晓军 College of Optic-Electric Science and Engineering National University of Defense Technology

Limited by the precision of optical machining and assembling, the optical axes of lasers in an array cannot be strictly parallel to each other, which will result in the beam quality degradation of the combined beam. The tolerance on tilt error for coherent combining of fiber lasers is studied in detail. The complex amplitude distribution in the far field for the gaussian beam with tilt angle is obtained by a novel coordinate transform method. Effect of tilt error on coherent combining is modelled analytically. Beam propagation factor is used to evaluate the effect of coherent combining. Numerical results show that for ring-distributed fiber laser array with central wavelength A and geometry size D, if the root-mean-square （RMS） value of the tilt error is smaller than 0.72A/D, the energy encircled in the diffraction-limited bucket can be ensured to be more than 50% of the value when there is no tilt error. The results are helpful to the designing and manufacturing of fiber array for coherent combining.

关键词： Fibers Fourier transforms gaussian beams Lasers

Innovative confocal laser method for exact dioptric power measurement of intraocular lens implants Invited Paper

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Chinese Optics Letters 2008年第12期6卷 876-878页

作者： Ilko K.Ilev Robert W.Faaland Do-Hyun Kim Robert H.James Don Calogero Office of Science and Engineering Laboratories Center for Devices and Radiological Health U.S.Food and Drug Administration10903 New Hampshire AvenueSilver Spring Office of Device Evaluation Center for Devices and Radiological Health U.S.Food and Drug Administration9200 Corporate BoulevardRockville

We present a novel confocal laser method （CLM） for precise testing of the dioptric power of both positive and negative intraocular lens （IOL） implants. The CLM principle is based on a simple fiber-optic confocal laser design including a single-mode fiber coupler that serves simultaneously as a point light source used for formation of a collimated gaussian laser beam, and as a highly sensitive confocal point receiver. The CLM approach provides an accurate, repeatable, objective, and fast method for IOL dioptric power measurement over the range from 0 D to greater than ±30 D under both dry and in-situ simulated conditions.

关键词： Crystalline lens Fiber optic couplers gaussian beams Intraocular lenses Laser beams Single mode fibers

Propagation of Helmholtz-Gauss beams in weak turbulent atmosphere

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Chinese Optics Letters 2008年第2期6卷 79-82页

作者：张逸新朱拓 School of Science Southern Yangtze University

Based on the Rytov approximation of light propagation in weak turbulent atmosphere, the closed-form expressions of field and average irradiance of each one of the four fundamental families of Helmholtz-Gauss （HzG） beams： cosine-Gauss beams, stationary Mathieu-Gauss beams, stationary parabolic-Gauss beams, and Bessel-Gauss beams, which are propagating in weak turbulent atmosphere, are obtained. The results show that the field and average irradiance can be written as the product of four factors： complex amplitude depending on the z-coordinate only, a gaussian beam, a factor of complex phase perturbation induced by atmospheric turbulence, and a complex scaled version of the transverse shape of the non-diffracting beam. The effect of weak atmospheric turbulence on irradiance distribution of the HzG beam can be ignored.

关键词： Atmospheric turbulence gaussian beams

Beam steering of external cavity diode laser by an intracavity electro-optic ceramic deflector

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Chinese Optics Letters 2011年第8期9卷 62-65页

作者：高敏叶青董作人卞正兰方祖捷蔡海文瞿荣辉 Shanghai Key Laboratory of All Solid-State Laser and Applied Techniques Shanghai Institute of Optics and Fine MechanicsChinese Academy of Sciences Graduate University of Chinese Academy of Sciences

A novel beam-steering external cavity diode laser using an intracavity lead lanthanum zirconate titanate （PLZT） electro-optic ceramic deflector is proposed and demonstrated experimentally. The laser consists of a semiconductor laser with single mode fiber coupled output, polarization controller, PLZT electro-optic ceramic deflector, and output concave mirror. By applying proper driven electrical signals on the PLZT electro-optic deflector, the beam deflection angle achieves 5.8 mrad at 1 000 V. A high-speed beam-steering property with less than 120-ns switching time is also observed. Moreover, a good beam quality with

关键词： Ceramic materials Electric properties gaussian beams Mirrors Polarization Semiconductor diodes Single mode fibers Solid state lasers