公开(公告)号：US20240337536A1

公开(公告)日：2024-10-10

申请号：US18413015

申请日：2024-01-15

申请人： Shanghai Jiao Tong University

发明人： Liangjun LU ,  Tianyu CHENG ,  Linjie ZHOU ,  Jianping CHEN ,  Jiao LIU

IPC分类号： G01J3/45 ,  G01J3/453 ,  G02F1/21 ,  G02F1/225

CPC分类号： G01J3/45 ,  G02F1/212 ,  G02F1/2252 ,  G01J2003/4538

摘要： An on-chip Fourier transform spectrometer based on a double-layer spiral waveguide comprises, in order, a waveguide input coupler, a 1×N optical splitter, N double-layer waveguide Y-branch structures, N double-layer spiral waveguides with incremental lengths, N double-layer waveguide Y-branch structures arranged in opposite directions, and N germanium-silicon detectors. The group index difference between the odd mode and the even mode in the double-layer waveguide makes the double-layer spiral waveguide function like an asymmetric Mach-Zehnder interferometer. N double-layer spiral waveguides with incremental lengths are used to achieve a spatial heterodyne based Fourier transform spectrometer. Spectral reconstruction from the measured interference fringes can be achieved by a regression algorithm. The invention meets the application need for miniaturization and portability of Fourier transform spectrometers, and has lower temperature sensitivity compared with the existing on-chip spectrometers on the silicon platform.