MONITOR-REGION EXPANSION MEMBER AND VEHICLESURROUNDINGS MONITOR USING THE SAME

摘要

PROBLEM TO BE SOLVED: To put a driver of a vehicle under conditions permitting improved visibility by expanding the monitor region around the vehicle by a monitor- region expansion member and producing improved monitor images with shaded portions by its total reflection being eliminated. SOLUTION: A monitor-region expansion member 12 comprises an upper image-moving part 122 having a substantially-halved cone type prism structure 122strct of which prism vertical angleθorθW becomes largest at the center of the member and gradually decreases as approaching from the center of the member toward the edge thereof, and an upper image-compressing part 124 having a surface-curved cylindrical structure 124strct which has an angle gradually decreased from the prism vertical angleθorθW of the upper image- moving part 122. A vehicle-surroundings monitor employs the monitor-region expansion member 12 as its optical image-forming means.