title: Near-field speckles produced by random self-affine surfaces and their contrast transitions.
abstract: By use of a numerical calculation based on Green's integral equation, we study the near-field speckles produced by the random self-affine fractal surfaces of a dielectric medium. The speckle intensities evolve considerably in the near-field region, and the local fluctuations in them disappear before they have traversed the distance of a wavelength. The transition of the speckle contrast either on the surface or in the near field and in the neighborhood non-near-field regions depends on lateral correlation length xi and roughness exponent alpha of the random surfaces.
authors.affiliation: Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, P.O. Box 800-211, Shanghai, China. chengchuanfu@yahoo.com
authors.forename: Chuanfu
authors.initials: C
authors.lastname: Cheng
authors.forename: Chunxiang
authors.initials: C
authors.lastname: Liu
authors.forename: Xiaorong
authors.initials: X
authors.lastname: Ren
authors.forename: Man
authors.initials: M
authors.lastname: Liu
authors.forename: Shuyun
authors.initials: S
authors.lastname: Teng
authors.forename: Zhizhan
authors.initials: Z
authors.lastname: Xu