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Updated: Mar 24, 2026
06:48
A Multimodal Wide-Field Fourier-Transform Raman Microscope
Published on: December 30, 2025
690
Phase-shift effect of amplitude spread function on spectrum and image formation in coherent Raman scattering
Summary
Coherent Raman scattering microspectroscopy
Area of Science:
- Optical Microscopy
- Spectroscopy
- Biomedical Imaging
Background:
- Coherent Raman scattering (CRS) microspectroscopy enables label-free hyperspectral imaging.
- Understanding factors affecting spectral and image quality is crucial for CRS applications.
Purpose of the Study:
- To theoretically investigate the phase-shift effect on the impulse response function in CRS.
- To analyze the impact of this effect on spectral and image-forming properties.
Main Methods:
- Theoretical analysis of the phase-shift effect in CRS.
- Investigation of the influence of objective numerical apertures (NA(ex) and NA(col)) on spectral and image properties.
Main Results:
- The spectrum and image in CRS are affected by both excitation and collection numerical apertures, alongside the phase-shift effect.
- Asymmetric numerical apertures (NA(ex)≠NA(col)) lead to spectral and image deformation, enabling direct measurement of the imaginary part of nonlinear susceptibility in CARS.
- Nonresonant background in SRS microscopy can cause image artifacts.
Conclusions:
- The phase-shift effect significantly influences CRS spectral and imaging characteristics.
- This effect offers new possibilities for quantitative measurements in CARS.
- Artifacts in SRS microscopy due to nonresonant background require careful consideration.
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