Chromatic aberration compensation in multiplex coherent Raman microscopy using a Bessel beam

Area of Science:

• Optics and Photonics
• Spectroscopy
• Microscopy

Background:

• Multiplex coherent anti-Stokes Raman scattering (CARS) microscopy offers label-free, ultra-broadband spectroscopic imaging.
• Chromatic aberration under high numerical aperture conditions degrades CARS imaging quality by causing axial splitting of the illumination spot, weakening spectral peaks.

Purpose of the Study:

• To develop a method to compensate for chromatic aberration in CARS microscopy without altering objective lenses.
• To simultaneously achieve broadband spectroscopy and high spatial resolution imaging using CARS.

Main Methods:

• Utilized Bessel beam illumination to counteract chromatic aberration.
• Combined the nonlinear CARS process with the axial elongation properties of Bessel beams.
• Performed numerical simulations and experimental validation.

Main Results:

• Bessel beam illumination successfully compensated for chromatic aberration in CARS microscopy.
• The combined approach achieved simultaneous broadband spectroscopy and high spatial resolution imaging.
• Demonstrated the effectiveness of the method without modifying objective lenses.

Conclusions:

• The proposed method effectively addresses chromatic aberration in CARS microscopy.
• Bessel beam illumination enhances the applicability of vibrational spectroscopic imaging techniques.
• This approach holds promise for expanding the capabilities of label-free imaging.