Imaging in thick samples, a phased Monte Carlo radiation transfer algorithm.

Area of Science:

• Optical imaging and microscopy
• Computational modeling and simulation

Background:

• Optical microscopy offers high resolution but is limited by scattering in complex samples.
• Lightsheet microscopy improves 3D resolution and reduces phototoxicity, but scattering remains a challenge.
• Comparing different scattering mitigation strategies in optical imaging is difficult.

Purpose of the Study:

• To develop a predictive tool for comparing optical illumination strategies in scattering media.
• To validate a novel phase-encoded Monte Carlo (φMC) algorithm against experimental data.
• To assess the comparative performance of Gaussian and Bessel beams in optical imaging.

Main Methods:

• Development of a phase-encoded Monte Carlo (φMC) radiation transfer algorithm.
• Modeling of interference phenomena, including Gaussian and Bessel beams.
• Experimental validation of the φMC model with varying illumination strategies.

Main Results:

• The φMC algorithm accurately models interference phenomena and experimental outcomes.
• For homogeneous scattering samples, Bessel beams offer no significant advantage over Gaussian beams in resolution or contrast.
• Bessel beams provide a greater depth of focus compared to Gaussian beams.

Conclusions:

• The φMC algorithm is a powerful predictive tool for optical imaging in thick, scattering samples.
• It is adaptable to various illumination geometries, sample properties, and beam types.
• The findings suggest that for homogeneous scattering, the choice between Gaussian and Bessel beams may depend on the need for extended depth of focus.