Event Ellipsometer: Event-based Mueller-Matrix Video Imaging

TL;DR

The paper introduces Event Ellipsometer, a novel system that captures Mueller-matrix videos of dynamic scenes at 30fps using an event camera and rotating QWPs, enabling real-time polarization imaging.

Contribution

It presents a new method combining event-based imaging with ellipsometry, allowing fast Mueller-matrix video acquisition for dynamic scenes.

Findings

Achieves 30fps Mueller-matrix video imaging.

Develops a calibration and reconstruction method for event-based ellipsometry.

Extends ellipsometry to dynamic, real-time scenes.

Abstract

Light-matter interactions modify both the intensity and polarization state of light. Changes in polarization, represented by a Mueller matrix, encode detailed scene information. Existing optical ellipsometers capture Mueller-matrix images; however, they are often limited to capturing static scenes due to long acquisition times. Here, we introduce Event Ellipsometer, a method for acquiring a Mueller-matrix video for dynamic scenes. Our imaging system employs fast-rotating quarter-wave plates (QWPs) in front of a light source and an event camera that asynchronously captures intensity changes induced by the rotating QWPs. We develop an ellipsometric-event image formation model, a calibration method, and an ellipsometric-event reconstruction method. We experimentally demonstrate that Event Ellipsometer enables Mueller-matrix video imaging at 30fps, extending ellipsometry to dynamic scenes.