Probability density function and detection threshold in high contrast imaging with partially polarized light

TL;DR

This paper derives the probability density function for speckles in high contrast imaging with partially polarized light and assesses detection thresholds, revealing unpolarized light's advantage in certain imaging conditions.

Contribution

It provides a new expression for the PDF of speckles with arbitrary polarization and analyzes detection thresholds, highlighting the benefits of unpolarized light in specific scenarios.

Findings

Unpolarized light offers an advantage in high contrast imaging with low DL PSF to halo ratios.

Derived the PDF for speckles formed by partially polarized light.

Calculated detection thresholds at 5-sigma confidence level.

Abstract

We obtain an expression for the probability density function (PDF) of partially developed speckles formed by light with an arbitrary degree of polarization. From the probability density we calculate the detection threshold corresponding to the 5sigma confidence level of a normal distribution. We show that unpolarized light has an advantage in high contrast imaging for low ratios of the deterministic part of the point spread function (DL PSF) to the halo, typical in coronagraphy.