Mirror Surface Reconstruction Using Polarization Field

Mirror surfaces are notoriously difficult to reconstruct. In this paper, we present a novel computational imaging approach for reconstructing complex mirror surfaces using a dense illumination field with angularly varying polarization states, which we call the polarization field. Specifically, we generate the polarization field using a commercial LCD with the top polarizer removed. We mathematically model the liquid crystals as polarization rotators using Jones calculus and show that the rotated polarization states of outgoing rays encode angular information (e.g., ray directions). To model reflection under the polarization field, we derive a reflection image formation model based on the Fresnel's equations and estimate incident ray positions and directions by coding the polarization field. Finally, we triangulate the incident rays with the camera rays to recover normals/depths of the mirror surface. Comprehensive simulations and real experiments demonstrate the effectiveness of our approach.