Prism-based tri-aperture laparoscopic objective for multi-view acquisition

This paper presents the design and prototype of a novel tri-aperture monocular laparoscopic objective that can acquire both stereoscopic views for depth information and a wide field of view (FOV) for situational awareness. The stereoscopic views are simultaneously captured via a shared objective with two displaced apertures and a custom prism. Overlapping crosstalk between the stereoscopic views is diminished by incorporating a strategically placed vignetting aperture. Meanwhile, the wide FOV is captured via a central third aperture of the same objective and provides a 2D view of the surgical field 2x as large as the area imaged by the stereoscopic views. We also demonstrate how the wide FOV provides a reference data set for stereo calibration, which enables absolute depth mapping in our experimental prototype.