a Institute of Optoelectronic Information, Yibin University, Yibin 644007, China; b Institute of Laser Physics & Chemistry, Sichuan University, Chengdu 610064, China
Abstract The concept of partially coherent nonparaxial modified Bessel--Gauss (MBG) beams is proposed. Based on the generalized Rayleigh-Sommerfeld diffraction integral, the analytical propagation equations of nonparaxial MBG beams in free space are derived and analysed, and some special cases are discussed. In particular, under the paraxial approximation our results reduce to the corresponding paraxial ones. Numerical calculation examples are given to illustrate the dependence of intensity and spectral degree of coherence on the beam order $m$, $\xi $ and $f$ parameters, and to compare the difference between the paraxial and nonparaxial results.
Received: 22 June 2005
Revised: 24 October 2005
Accepted manuscript online:
PACS:
42.60.Jf
(Beam characteristics: profile, intensity, and power; spatial pattern formation)
Fund: Project supported by the National High Technology Development Program of China (Grant No 823070) and the National Natural Science Foundation of China (Grant No 10574097).
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