Design and evaluation of binocular stereoscopic system with variable vergence mechanism for near-field operation

In general tele-operation, an operator watches a video captured by a remote camera to perceive the scene of the target operating space. However, typical monocular video diminishes the perceptivity and comfort of its operator because of the lack of a sense of depth. To provide a sense of depth, a binocular stereoscopic camera and 3D display are employed for a tele-operation system. In general, a stereoscopic camera must be adjusted for parallax, especially for near-field shooting. Therefore, a control strategy for the parallax of a binocular stereoscopic vision system is investigated. One of the serious issues for 3D displays is the vergence-accommodation conflict. Therefore, the proposed system controls its vergence angle to resolve the conflict for an object watched by an operator. To evaluate the perceptivity of the system, sensory evaluations were conducted using the proposed stereoscopic system that consists of a 3D display and pan-tiltvergence (PTV) controllable binocular stereoscopic camera. When the binocular parallax was controlled as proposed, the task completion time was shortened, and the correctness of a 2D-3D distinction test was improved. These results verified that the proposed system improves the perceptivity of the remote space, especially for near-field operation.