BLIND SEPARATION BASED HIGH ACCURACY PERSPECTIVE DETECTION METHOD FOR MULTILAYER COMPLEX STRUCTURE MATERIAL

摘要

The present disclosure discloses a blind separation based high accuracy perspective detection method for a multilayer complex structure material. The method is achieved through blind separation of single channel periodic signals and frequency modulation interference of laser wave numbers. In this method, time series interference images captured by a photodetector are subjected to zero mean normalization; a vector Θ of amplitude, frequency and phase field, which is to be solved and reflects characteristics of each interface in the multilayer complex-structure material, is created and is solved using a mathematical optimization method; a phase field distribution of the vector Θ is finally extracted and is subjected to phase unwrapping, to realize high accuracy detection on an internal distribution of the multilayer complex structure material. The present disclosure has advantages that limitation on a Nyquist depth measurement resolution caused by a limited laser wave number frequency sweep range is overcome, and high accuracy distribution conditions of each interface layer in the multilayer complex-structure material can be acquired.