| 摘要 |
PURPOSE: To prevent the tilt angle of a reflecting mirror from being determined by the tilt angle of a lens and to eliminate a designing restriction by providing a prism in the direction to mitigate the inclination of a plane on the lens, and inclining the optical axis of the reflecting mirror by nearly the same angle as the apex of the prism in the direction along the perpendicular of the plane. CONSTITUTION: The lens 2 of a headlight for a vehicle having the inclined lens 2 is provided with a prism 2a having the apex angleαof 4 deg. or above and arranged in the direction to mitigate the inclination of a plane, and the optical axis of a reflecting mirror 3 is inclined by nearly the same angleβas the apex angleαat the prism 2a in the direction along the perpendicular of the plane. The inclination of the reflecting mirror 3 can freely be selected regardless of the inclination of the lens 2, and the change of radiation illuminance can freely be set in response to a specification. Since the apex angleαof the prism 2a can be set freely, even the lens 2 having a large slant angle can be manufactured at a proper thickness. |
