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arXiv · 2411.17313

Event Ellipsometer: Event-based Mueller-Matrix Video Imaging

Ryota Maeda·Yunseong Moon·Seung-Hwan Baek
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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.

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Ryota Maeda, Yunseong Moon, Seung-Hwan Baek. 2025-04-06. Event Ellipsometer: Event-based Mueller-Matrix Video Imaging. https://arxiv.org/abs/2411.17313

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