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Updated: May 20, 2026

A Multimodal Wide-Field Fourier-Transform Raman Microscope
Published on: December 30, 2025
Note: improving spatial resolution of optical frequency-domain reflectometry against frequency tuning nonlinearity
Zhenyang Ding1, Tiegen Liu, Zhuo Meng
1College of Precision Instrument and Opto-Electronics Engineering, Tianjin University, Tianjin 300072, China.
Abstract:
We propose using non-uniform FFT to minimize the degrading effect of frequency tuning nonlinearity of a tunable laser source (TLS) in an optical frequency-domain reflectometry (OFDR) system. We use an auxiliary interferometer to obtain the required instantaneous optical frequency of the TLS and successfully demonstrate 100 times enhancement in spatial resolution of OFDR with only a 20% increase in computation time. The corresponding measurement reflectivity sensitivity is better than -80 dB, sufficient to detect bending induced index changes in an optical fiber.
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