| 摘要 |
PURPOSE: To form a vivid light and shade boundary by obtaining a high luminous intensity right below the light and shade boundary to make a big beam effective distance, by forming a cross section curve with eccentricity made variable throughout its entire circumference on the cross section of a reflector. CONSTITUTION: A reflector 10 has mutually different reflecting surfaces in an upper region 19 and a lower region 20, the image formation of an illuminating body 13 is reflected by the reflecting surfaces, and a light distribution having a light and shade boundary 30 provided with an almost horizontal section 28 and a section 36 inclined relative to the horizontal surface at a designated angleαis formed. A cross section curve with eccentricity variably formed throughout its entire circumference is formed on the cross section of the reflector 10 cut perpendicularly to an optical axis 14, and an image formation 25 reflected by the region 19 of the body 13 and located at the highest position is brought into contact with the section 28 of the boundary 30 at its upper rim. The image formation reflected by the region 20 and located at the highest position is also brought into contact with the section 36 of the boundary 30. Thereby, a high luminous intensity can be obtained right below the boundary 30 and a big beam effective distance can be obtained as a result. |
