| 摘要 |
PURPOSE:To improve visibility by improving an upper edge cut property of an irradiation pattern of a headlamp using a doublefilament bulb. CONSTITUTION:A double-filament bulb 2 and a front face lens 7 are arranged before a reflector l. A reflecting mirror surface of the reflector l is divided into right/left parabolic reflecting mirror surfaces 3a, 3a having a focal distance (f) almost equal on an optical axis L of the reflecting mirror surface and further having a focal point F1 in a position of a subfilament 5 constituted into the double-filament bulb 2, central part lower half parabolic reflecting mirror surface 3c having a focal point F2 a little before the position F1 and a central part upper half parabolic reflecting surface 3b having a focal point position F3 a little after the position F1. A main filament 4 and the subfilament 5 of the double-filament bulb 2 are selectively lighted to change a light distribution pattern. |
