Dual-spectrum laser source based on fiber continuum generation for integrated optical coherence and multiphoton...

Area of Science:

• Biomedical Optics
• Microscopy
• Laser Physics

Background:

• Integrated imaging modalities offer enhanced capabilities for biological research.
• Existing dual-spectrum sources often lack the optimal characteristics for both optical coherence microscopy (OCM) and multiphoton microscopy (MPM).

Purpose of the Study:

• To demonstrate a single-laser dual-spectrum source optimized for integrated OCM and MPM.
• To extend the spectral range for combined OCM-MPM imaging.
• To validate the source's performance using biological samples.

Main Methods:

• Utilized a tunable, mode-locked Ti-sapphire laser.
• Employed spectral broadening via continuum generation in a photonic crystal fiber for one output beam.
• Maintained the ultrashort pulses of the Ti-sapphire laser for the second output beam.

Main Results:

• The dual-spectrum source successfully performed both OCM and MPM.
• Continuum-broadened beam enhanced OCM optical sectioning; unbroadened beam optimized MPM excitation.
• The photonic crystal fiber demonstrated robustness with no damage after 100 hours of use.
• Demonstrated imaging of fluorescently labeled cells and unstained in vivo human skin across a wide spectral range.

Conclusions:

• The developed single-laser dual-spectrum source is feasible for integrated OCM-MPM.
• This technology facilitates new investigations in in vivo microscopy, tissue engineering, and cell biology.
• The source extends the spectral capabilities for advanced microscopy techniques.