Optical design of bi-freeform-prism for wide field-of-view low-distortion virtual stereo vision system

Abstract

Virtual stereoscopic vision systems are integral to modern optical technologies, yet correcting image distortion in wide FoV binocular systems remains a critical challenge. This study introduces a novel bi-freeform-prism design methodology to address distortion correction and enhance system performance. An improved virtual camera model with a consistency constraint is proposed to resolve convergence issues in traditional approaches, accompanied by a systematic analysis of system parameters and dimensions, and an optimized metric for evaluating virtual image quality. A prototype BFP-based system was fabricated, featuring a 1 mm entrance pupil, a 1.94 mm focal length, and a ${\mathrm{\pm \; 23}}^{\circ }\times {\mathrm{\pm \; 23}}^{\circ }$ FoV. Experimental results demonstrate distortion reductions to 1.23% and 1.74% for the left and right fields of view, respectively, validating the proposed BFP design as an effective solution for distortion correction in wide FoV systems.