| 摘要 |
PROBLEM TO BE SOLVED: To improve illumination to a space of nearer road boundary line and light guidance of a driver, and reduce a condition of dazzling drivers of cars on the opposite lane by constituting so that an inclination of facets to a vertical line of headlights, an extinction light source, diffusion of a light beam and widths of the facets respectively satisfy specific expressions. SOLUTION: Headlights 1 and 2 have facets 11, 12, 21 and 22 in the shape of a parabolic column forming profiles B and C above a horizontal line (z). In the case of the headlight 1, gradients to a vertical line (y) areα11 andα12 , and gradients in the case of the headlight 2 areα21 andα22 , and respectively satisfy expressions I and II. An extinction light source is also set so that a surface of its light source becomes a prescribed distanceΔf from a focus of a reflector, and satisfies expression III. In diffusion of a light beam, the size relationship between obliquely upward diffusionsβandεand obliquely downward diffusionsγandδsatisfies expression IV, and facet widths w11 and w12 of the headlight 1 and facet widths w21 and w22 also satisfy expression V. |
