Light Scattering By Inhomogeneous Particles And Its Applications

With the development of laser technology and weak signal detection techniques, light scattering characteristics of inhomogeneous particles and their applications become a hot research topic in recent years.Near-field scattering properties and coupling performances of spherical symmetry GRIN micro ball lens are discussed. Based on GLMT, the near-field scattering intensity distributions are calculated for a GRIN sphere illuminated by a Gaussian beam. The effects of refractive index distributions of Maxwell fisheye micro-lens and the incident conditions on the coupling performances are studied. For the application of GRIN micro ball lens, above analyses provide a more accurate and effective theoretical guidance.Laser rainbow measuring technique is employed to determine the optical parameters of fiber. On the basis of the simultaneous inversion method for diameter and refractive index of homogeneous spherical or cylindrical particles, the relation of ripple frequency to diameter and refractive index is gain at the wavelength of 532nm, and employed to the accurate and rapid measurement of the diameter and refractive index of a homogeneous single-mode fiber. The measurement method of refractive index distributions of radial GRIN cylinder is studied. The exponential factor g is obtained by using CSD method.Based on the intensity distributions in 1st rainbow region, a new method to determine azimuthal positions of polarization axes of Polarization-Maintaining fiber is presented. The rainbow intensity distributions are analyzed at different azimuthal positions of polarization axes. The cross correlation coefficients of the intensity distributions and the theoretical distributions of single-mode fiber are calculated. The azimuthal positions of polarization axes are obtained exactly by analyzing the variation of cross correlation coefficient. The method has the advantages of high speed, simple system structure, and convenient operation.