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.
© 2005 Optical Society of America
(000.3860) General : Mathematical methods in physics
(000.4430) General : Numerical approximation and analysis
(100.3190) Image processing : Inverse problems
(130.3120) Integrated optics : Integrated optics devices
(230.7370) Optical devices : Waveguides
Sailing He, Ran Liao, and Vladimir Romanov, "Explicit formulas for the identification of a small defect in a planar waveguide," J. Opt. Soc. Am. A 22, 1414-1419 (2005)