| 摘要 |
PURPOSE:To obtain a light distribution pattern with its hot zone, by providing a projection lens having the focus of each reflection surface situated in almost all the same position to each other, a light source arranged in the position of the focus and the focus also situated near the converging portion of each of the upper and lower reflection surfaces in front of the upper and lower reflection surfaces. CONSTITUTION:Upper and lower reflection surfaces 3, 4 are formed to have their respective reflection surfaces which are characterized by having reflected light focused in a long sideways fashion on a converging portion in front of the reflection surfaces. The application available to such reflection surfaces like these includes, for example, a parabola and ellipse compound plane which forms a parabola in a horizontal section and an ellipse in a vertical section while the axis of the parabola agrees with that of the ellipse and also the focus of the parabola agrees with a first focus of the ellipse, or another plane such as a plane, special elliptic plane, etc. in which both the horizontal section and the vertical section form an ellipse, both the axis and the first focus of the ellipse are made common and nevertheless the second focus of the ellipse on the vertical section is allowed to be situated remote from the second focus of the ellipse on the horizontal section. Accordingly, rays of light given out of a light source placed on the focus Fc of the upper and lower reflection surfaces 3, 4 and then reflected on the reflection surfaces 3, 4 are focused in a long sideways pattern on a converging portion F2 in front of the reflection surfaces. |
