A robust model transfer approach for portable Raman spectrometers: Enabling interoperable analysis across measurement...

Area of Science:

• Analytical Chemistry
• Spectroscopy
• Materials Science

Background:

• Handheld Raman spectroscopy enables rapid, on-site analysis but suffers from instrument-to-instrument spectral discrepancies.
• These nonlinear variations hinder data comparability and limit the integration of diverse handheld Raman systems.
• Accurate spectral alignment is crucial for reliable cross-platform analysis.

Purpose of the Study:

• To develop a standard-material-based model transfer approach for aligning handheld Raman spectra with benchtop microscopic Raman instruments.
• To establish a high-fidelity mapping correcting nonlinear wavenumber shifts while preserving spectral features.
• To enhance cross-instrument reliability and enable interoperable analysis.

Main Methods:

• Utilized a standard-material-based model transfer approach.
• Integrated wavenumber calibration, multiscale convolution, and an attention-guided segmented transfer strategy.
• Mapped handheld spectra to microscopic Raman reference profiles.

Main Results:

• Successfully corrected nonlinear wavenumber shifts and preserved key spectral features (peak positions, intensities, shape).
• Significantly reduced peak position root-mean-square error (RMSE) across various analytes.
• Enhanced spectral similarity metrics (SAM, DTW, MMD) and improved downstream classification task performance.

Conclusions:

• The proposed framework provides a robust solution for spectral consistency across Raman platforms.
• Achieved enhanced cross-instrument reliability, supporting interoperable analysis in different environments.
• Laid the foundation for multi-instrument spectral harmonization in Raman spectroscopy.