A vision sensor having an expanded dynamic range for autonomous vehicles

Insufficiency of dynamic range of conventional video cameras is an important problem in realizing a robust vision system for autonomous vehicles because road scenes have a very wide dynamic range of brightness. To solve the problem, a method for expanding the dynamic range of video cameras by combining the images taken under different exposure conditions has been developed. Using this method, an experimental vision sensor with a wide dynamic range has been manufactured. The developed sensor has a dynamic range of 10 000, which is approximately 30 times as wide as that of a conventional video camera. The effectiveness of the developed vision sensor in comparison with a conventional video camera was confirmed from the experiments on a highway under various lighting conditions.