Rapid spectral shaping for time domain and swept source full field OCT

Area of Science:

• Biomedical Optics
• Optical Imaging
• Medical Physics

Background:

• Full-field optical coherence tomography (FFOCT) is gaining traction due to advancements in dynamic and swept-source OCT.
• Current FFOCT systems face limitations in wavelength selection and axial resolution, restricting their application.
• A need exists for more versatile and higher-resolution FFOCT imaging solutions.

Purpose of the Study:

• To develop a novel method for rapid spectral shaping in FFOCT imaging.
• To create a flexible light source compatible with FFOCT systems.
• To enhance axial resolution and imaging speed in FFOCT.

Main Methods:

• A supercontinuum laser was combined with a fast acousto-optic tunable filter (AOTF).
• A multimode fiber with passive and active mode mixing was utilized for spectral shaping.
• The AOTF frequency was tuned to generate desired spectra (575-1000 nm) for time-domain FFOCT or swept-source FFOCT.

Main Results:

• An extremely flexible light source compatible with FFOCT was successfully developed.
• The method allows for the creation of any spectrum of interest within the 575-1000 nm range.
• Achieved swept-source FFOCT at up to 100 kfps with an axial resolution of 1.1 μm.

Conclusions:

• The developed spectral shaping method significantly enhances the flexibility of FFOCT light sources.
• This technique overcomes limitations in wavelength selection and axial resolution for FFOCT.
• The system enables high-speed, high-resolution FFOCT imaging, opening new possibilities for applications.