title: Explicit formulas for the identification of a small defect in a planar waveguide.
abstract: Nondestructive testing of a small defect (a dust particle or air void) in a strongly confined planar waveguide is considered. Explicit formulas are given for a quick identification of the small defect by use of the distorted fields measured at the two end faces of the planar waveguide for two frequencies. The explicit identification scheme is verified numerically.
authors.affiliation: Centre for Optical and Electromagnetic Research, State Key Laboratory of Modern Optical Instrumentation, Zhejiang University, Yu-Quan, Hangzhou 310027, China. sailing@kth.se
authors.forename: Sailing
authors.initials: S
authors.lastname: He
authors.forename: Ran
authors.initials: R
authors.lastname: Liao
authors.forename: Vladimir
authors.initials: V
authors.lastname: Romanov