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学术活动
Uniqueness and numerical method for phaseless inverse diffraction grating problem with known superposition of incident point sources
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报告人:
Junliang Lv, Professor, Jilin University
邀请人:
Tao Yin, Associate Professor
题目:
Uniqueness and numerical method for phaseless inverse diffraction grating problem with known superposition of incident point sources
时间地点:
10:00-11:00 March 29 (Friday), N208
摘要:

In this talk, I will introduce some results on  uniqueness and numerical methods of identifying a smooth grating profile with a mixed or transmission boundary condition from phaseless data. The existing uniqueness result requires the measured data to be in a bounded domain. To break this restriction, we design an incident system consisting of the superposition of point sources to reduce the measurement data from a bounded domain to a line above the grating profile. We derive reciprocity relations for point sources, diffracted fields, and total fields, respectively. Based on Rayleigh's expansion and reciprocity relation of the total field, a grating profile with a mixed or transmission boundary condition can be uniquely determined from the phaseless total field data. An iterative algorithm is proposed to recover the Fourier modes of grating profiles at a fixed wavenumber. Some numerical examples are presented to verify the correctness of theoretical results and to show the effectiveness of our numerical algorithm.