Label-free multimodal nonlinear microscopy enabled by an optical parametric generator.

Area of Science:

• Nonlinear Optics
• Microscopy
• Laser Technology

Background:

• Nonlinear optical microscopy relies heavily on laser advancements.
• A need exists for laser sources offering high peak power, wavelength tunability, and multimodal imaging capabilities in an accessible setup.

Purpose of the Study:

• To present a novel optical parametric generator (OPG) system for nonlinear optical microscopy.
• To demonstrate the OPG's capability for broadband, tunable femtosecond radiation suitable for multimodal imaging.

Main Methods:

• Developed an optical parametric generator (OPG) system bypassing optical cavities and amplification stages.
• Validated the OPG using coherent anti-Stokes Raman scattering (CARS) spectroscopy and microscopy.
• Demonstrated multimodal imaging by co-registering multiphoton autofluorescence, second-harmonic generation, and CARS.

Main Results:

• The OPG system provides tunable radiation over 100 nm near 1500 nm.
• Successfully acquired CARS spectra and performed CARS microscopy on tissue specimens.
• Enabled label-free multimodal imaging, combining CARS, multiphoton autofluorescence, and second-harmonic generation.

Conclusions:

• The OPG system offers a versatile and cost-effective solution for multimodal nonlinear optical microscopy.
• Its simple, modular design makes it adaptable for various applications requiring broadband, tunable femtosecond lasers.