公开(公告)号：US4907877A

公开(公告)日：1990-03-13

申请号：US270430

申请日：1988-11-09

申请人： Yutaka Fukuda ,  Koji Minagawa ,  Hiroichi Nabeshima ,  Koichiro Muneki ,  Yoshikatsu Asano ,  Kazuo Aoki ,  Yutaka Ishizaka

发明人： Yutaka Fukuda ,  Koji Minagawa ,  Hiroichi Nabeshima ,  Koichiro Muneki ,  Yoshikatsu Asano ,  Kazuo Aoki ,  Yutaka Ishizaka

IPC分类号： G01M11/06

CPC分类号： G01M11/065 ,  G01M11/064

摘要： A method and apparatus for determining or adjusting a projecting direction of a light beam emitted from an automobile headlight is provided. In a first aspect of the present invention, the peripheral region of a light beam is used in determining its projecting direction. In particular, a region definable in a light pattern of the projected beam having a proportionality relation between log S and I, where S indicates the value of an area having light intensity I or above, is determined and its outer contour or any predetermined point in the contour is used in determining the projecting direction. In a second aspect, apparatus for determining a projecting direction of a light beam emitted from an automobile headlight includes an indicator which automatically indicates a predetermined position of a light pattern of the light beam projected. In a third aspect, there is provided a system for automatically adjusting a projecting direction of a light beam if it deviates from a predetermined direction using a motor engageable with a mounting structure of the headlight.