Optical dispersions through intracellular inhomogeneities

TL;DR

This paper extends the Transport of Intensity Equation (TIE) to account for intracellular refractive index turbulence modeled as fractal structures, enabling better understanding and measurement of optical dispersions in biological cells.

Contribution

It introduces a fractal-based modification of TIE for intracellular media and demonstrates how intensity dispersion relates to fractal dimensions and wavelengths.

Findings

Simulation shows intensity dispersion depends on fractal dimension and wavelength.

Provides a method for direct measurement of intracellular fractal profiles.

Links fractal organization to optical transmissivity in biological imaging.

Abstract

Transport of intensity equation (TIE) exhibits a non-interferometric correlation between intensity and phase variations of intermediate fields (e.g., light and electron) in biological imaging. Previous TIE formulations have generally assumed a free space propagation of monochromatic coherent field functions crossing phase distributions along a longitudinal direction. Here, we modify the TIE with fractal (or self-similar) organization models based on intracellular refractive index turbulence. We then implement the TIE simulation over a broad range of fractal dimensions and wavelengths. Simulation results show how the intensity propagation through the spatial fluctuation of intracellular refractive index interconnects fractal-dimensionality with intensity dispersion (or transmissivity) within the picometer to micrometer wavelength range. In addition, we provide a spatial-autocorrelation of phase derivatives which allows the direct measurement and reconstruction of intracellular fractal profiles from optical and electron microscopy imaging.