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1.
Based on the vectorial Rayleigh-Sommerfeld integral formulae,this paper derives the analytical nonparaxial propagation equation of a super-Lorentz-Gauss (SLG) SLG 01 mode beam in free space.The far field expression and the scalar paraxial result are treated with special cases of the general formulae.According to the obtained analytical representation,the nonparaxial propagation properties of the SLG 01 mode beam are illustrated and analysed with numerical examples.This research provides an approach to investigate the propagation of the SLG 01 mode beam within the framework of the nonparaxial regime. 相似文献
2.
This paper derives the closed-form expressions for nonparaxial phase flipped Gaussian (PFG) beams propagating in free space, through a knife edge and an aperture, which enable us to study nonparaxial propagation properties of PFG beams and to compare nonparaxial results with paraxial ones. It is found that the f parameter, offsetting distance of the knife edge and truncation parameter affect the nonparaxial beam propagation properties. Only under certain conditions the paraxial approximation is applicable. The results are illustrated by numerical examples. 相似文献
3.
The Wigner distribution functions of coherent and partially coherent Bessel-Gaussian beams 下载免费PDF全文
Based on the integral representation of the Bessel functions and the generating function of the Tricomi function,an analytical expression of the Wigner distribution function(WDF) for a coherent or partially coherent Bessel-Gaussian beam is presented.The reduced two-dimensional WDFs are also demonstrated graphically,which reveals the dependence of the reduced WDFs on the beam parameters. 相似文献
4.
Based on the vectorial Rayleigh--Sommerfeld integral
formulae, this paper derives the analytical nonparaxial propagation
equation of a super-Lorentz--Gauss (SLG) SLG01 mode beam in
free space. The far field expression and the scalar paraxial result
are treated with special cases of the general formulae.
According to the obtained analytical representation, the nonparaxial
propagation properties of the SLG01 mode beam are illustrated
and analysed with numerical examples. This research provides an
approach to investigate the propagation of the SLG01 mode beam
within the framework of the nonparaxial regime. 相似文献
5.
Propagation factor of electromagnetic concentric rings Schell-model beams in non-Kolmogorov turbulence 下载免费PDF全文
We derive an analytical expression for the propagation factor(known as M2-factor) of electromagnetic concentric rings Schell-model(EM CRSM) beams in non-Kolmogorov turbulence by utilizing the extended Huygens–Fresnel diffraction integral formula and the second-order moments of the Wigner distribution function(WDF). Our results show that the EM CRSM beam has advantage over the scalar CRSM beam for reducing the turbulence-induced degradation under suitable conditions. The EM CRSM beam with multi-rings far-fields in free space is less affected by the turbulence than the one with dark-hollow far-fields or the electromagnetic Gaussian Schell-model(EGSM) beam. The dependence of the M2-factor on the beam parameters and the turbulence are investigated in detail. 相似文献
6.
Characteristics of paraxial propagation of a super Lorentz—Gauss SLG01 mode in uniaxial crystal orthogonal to the optical axis 下载免费PDF全文
Analytical propagation expression of a super Lorentz-Gauss(SLG) 01 mode in uniaxial crystal orthogonal to the optical axis is derived.The SLG 01 mode propagating in uniaxial crystal orthogonal to the optical axis mainly depends on the ratio of the extraordinary refractive index to the ordinary refractive index.The SLG 01 mode propagating in uniaxial crystals becomes an astigmatic beam.The beam spot of the SLG 01 mode in the uniaxial crystal is elongated in the x-or y-direction,which is determined by the ratio of the extraordinary refractive index to the ordinary refractive index.With the increase of the deviation of the ratio of the extraordinary refractive index to the ordinary refractive index from unity,the elongation of the beam spot also augments.In different observation planes,the phase distribution of an SLG 01 mode in the uniaxial crystal takes on different shapes.With the variation of the ratio of the extraordinary refractive index to the ordinary refractive index,the phase distribution is elongated in one transversal direction and is contracted in the other perpendicular direction.This research is beneficial to the practical applications of an SLG mode. 相似文献
7.
Characteristics of paraxial propagation of a super Lorentz-Gauss SLG<sub>01</sub> mode in uniaxial crystal orthogonal to the optical axis 下载免费PDF全文
Analytical propagation expression of a super Lorentz-Gauss(SLG) 01 mode in uniaxial crystal orthogonal to the optical axis is derived.The SLG 01 mode propagating in uniaxial crystal orthogonal to the optical axis mainly depends on the ratio of the extraordinary refractive index to the ordinary refractive index.The SLG 01 mode propagating in uniaxial crystals becomes an astigmatic beam.The beam spot of the SLG 01 mode in the uniaxial crystal is elongated in the x-or y-direction,which is determined by the ratio of the extraordinary refractive index to the ordinary refractive index.With the increase of the deviation of the ratio of the extraordinary refractive index to the ordinary refractive index from unity,the elongation of the beam spot also augments.In different observation planes,the phase distribution of an SLG 01 mode in the uniaxial crystal takes on different shapes.With the variation of the ratio of the extraordinary refractive index to the ordinary refractive index,the phase distribution is elongated in one transversal direction and is contracted in the other perpendicular direction.This research is beneficial to the practical applications of an SLG mode. 相似文献
8.
XIAYong YINJian-Ping WANGYu-Zhu 《中国物理快报》2003,20(5):674-677
We propose a new method to generate a focused hollow laser beam by using an azimuthally distributed 2π-phase plate and a convergent thin lens,and calculate the intensity distribution of the focused hollow beam in free propagation space.The relationship between the waist w0 of the incident collimated Gaussian beam and the dark spot size of the focused hollow beam at the focal point,and the relationship between the focal lenght f of the thin lens and the dark spot size are studied respectively.The optical potential of the blue-detuned focused hollow beam for^85 Rb atoms is calculated.Our study shows that when the larger waist w of the incident Gaussian beam and the shorter focal length f of the lens are chosen,we can obtain an extremely small dark spot size of the focused hollow beam,which can be used to form an atomic lens with a resolution of sereval angstroms. 相似文献
9.
A further study on the spreading and directionality of Gaussian array beams in non-Kolmogorov turbulence 下载免费PDF全文
It is found that in free space, the curves of the mean-squared beam width may each have a cross point at a certain propagation distance Zc. For Gaussian array beams, the analytical expressions of zc are derived. For the coherent com- bination, Zc is larger than that for the incoherent combination. However, in non-Kolmogorov turbulence, the cross point disappears, and the Gaussian array beams will have the same directionality in terms of the angular spread. Furthermore, a short propagation distance is needed to reach the same directionality when the generalized exponent is equal to 3.108. In particular, it is shown that the condition obtained in previous studies is not necessary for laser beams to have the same directionality in turbulence, which is explained physically. On the other hand, the relative average intensity distributions at the position where the Gaussian array beams have the same mean-squared beam width are also examined. 相似文献
10.
Characterization of Nonparaxial Truncated Cosine-Gaussian Beams and the Beam Quality in the Far Field 下载免费PDF全文
The analytical expression characterizing the propagation of nonparaxial truncated cosine-Gaussian (COG) beams in free space is derived, and some special cases are discussed. The extended power in the bucket (PIB) is proposed to characterize the beam quality of nonparaxial truncated beams in the far field. It is shown that the extended PIB is applicable to nonparaxial truncated beams, and the PIB of nonparaxial truncated CoG beams depends on the decentred parameter, waist-width-to-wavelength ratio, truncation parameter, and bucket size chosen. 相似文献
11.
Guoquan Zhou 《Optics Communications》2010,283(7):1236-1243
Based on the generalized integral formula and the convolution theorem of the Fourier transform, an analytical propagation formula of a Lorentz-Gauss beam passing through a misaligned paraxial optical system is derived. As numerical examples, the propagation properties of a Lorentz-Gauss beam through a misaligned thin lens with the lateral displacement and the angle displacement are graphically illustrated, respectively. The influences of the lateral displacement and the angle displacement of the misaligned thin lens on the normalized light intensity and the phase distributions are also examined, respectively. 相似文献
12.
13.
Paraxial propagation of partially coherent flat-topped beam 总被引:3,自引:0,他引:3
The propagation of flat-topped beam passing through a paraxial optical ABCD system is extended to partially coherent case and has been studied in detail. Based on Wigner distribution function (WDF), the irradiance distribution of partially coherent flat-topped beam is derived. Furthermore, two propagation parameters, such as M2-factor and Power in Bucket (PIB) are illustrated analytically and numerically. 相似文献
14.
Kurtosis parameters of super Lorentzben Gauss beams through a paraxial and real ABCD optical system 下载免费PDF全文
Based on the propagation equation of higher-order intensity moments, analytical propagation expressions for the kurtosis parameters of a super Lorentz-Gauss (SLG) SLG01 beam through a paraxial and real ABCD optical system are derived. By replacing the parameters in the expressions of the kurtosis parameters of the SLG01 beam, the kurtosis parameters of the SLG10 and SLG11 beams through a paraxial and real ABCD optical system can be easily obtained. The kurtosis parameters of an SLG01 beam through a paraxial and real ABCD optical system depend on two ratios. One is the ratio of the transfer matrix element B to the product of the transfer matrix element A and the diffraction-free range of the super-Lorentzian part. The other is the ratio of the width parameter of the super-Lorentzian part to the waist of the Gaussian part. As a numerical example, the properties of the kurtosis parameters of an SLG01 beam propagating in free space are illustrated. The influences of different parameters on the kurtosis parameters of an SLG01 beam are analysed in detail. 相似文献
15.
The Lorentz and Lorentz-Gauss beams are extended to the nonparaxial regime. Analytical propagation expressions of nonparaxial Lorentz and Lorentz-Gauss beams in free space are derived, and the propagation of paraxial Lorentz and Lorentz-Gauss beams is treated as a special case of our general results. The propagation properties of Lorentz and Lorentz-Gauss beams are illustrated and compared with numerical examples. 相似文献
16.
《Physics letters. A》2006,360(2):394-399
Based on the generalized diffraction integral formula for treating the propagation of a laser beam through a misaligned paraxial ABCD optical system in the cylindrical coordinate system, analytical formula for a circular flattened Gaussian beam propagating through such optical system is derived. Furthermore, an approximate analytical formula is derived for a circular flattened Gaussian beam propagating through an apertured misaligned ABCD optical system by expanding the hard aperture function as a finite sum of complex Gaussian functions. Numerical examples are given. 相似文献
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18.
Based on scalar diffraction theory, propagation properties of beam generated by Gaussian mirror resonator were investigated. Explicit expressions for the field distribution of the beam that propagate through a paraxial optical ABCD system were derived and numerical examples were given to illustrate our analytical results. 相似文献
19.
By expanding the hard aperture function into a finite sum of complex Gaussian functions, some approximate analytical formulae for the cross-spectral density of a partially coherent flattened Gaussian beam (FGB) propagating through apertured aligned and misaligned ABCD optical systems are derived based on the generalized Collins formula. The results obtained by using the approximate analytical formula are in good agreement with those obtained by using the numerical integral calculation. As a numerical example, the focusing properties (including average irradiance distribution and focal shift) of a partially coherent FGB focused by an apertured thin lens are studied, and it is found that the focusing properties of a partially coherent FGB are closely related to its initial coherence and the aperture width. Our results provide an effective and fast way for studying the paraxial propagation of a partially coherent FGB through apertured ABCD optical systems. 相似文献
20.
将相位翻转高斯光束的概念推广到相位翻转高阶模光束.以相位翻转厄米-高斯光束为例,推导出相位翻转高斯光束通过近轴理想(无光阑)ABCD光学系统,以及带刀口和光阑的ABCD光学系统传输的递推方程,并用以研究相位翻转高斯光束的传输特性.特别是,得出对TEM1、TEM2和TEM3模相位翻转高斯光束,光阑效应可以忽略的条件分别是截断参量δ≥2.1,2.5和 3.0. 相似文献