Wide Angle Multi-Shift Stereo Camera with Monocular Vision

In recent years, following the development of automated driving (AD) and advanced driver assistance systems (ADAS), stereo cameras which are able to measure distance are advancing accordingly by employing wide-angle field of view to detect various objects. At the same time, demand for low cost stereo cameras which can detect far objects also exists. Also, detection distance performance degradation due to low resolution CMOS image sensors and distortion from wide-angle lenses remain as problems when increasing the stereo camera field of view (FOV). In order to solve such problems, we developed a multi-shift stereo camera. In the multi-shift method, the left and right CMOS image sensors are shifted their center with respect to each lens optical axis center. By using this method, far object detection performance can be preserved while obtaining a wider FOV without the use of an expensive image sensor. We also developed a monocular vision detection employing top view image subtraction method, enabling detection of pedestrians and cyclists in the monocular vision region which is created at the outer region of the camera FOV. Furthermore, by using the disparity information from the center region to estimate the camera posture, we can achieve high accuracy for detection and distance measurement at the monocular region.