| 摘要 |
PURPOSE:To expand an irradiation width and to be easily handled by providing the following: a lens face covering a whole width of an opening of a reflection frame; a curved surface whose radius is larger than a radius of the lens face or a rear surface composed of a plane which has been installed at the lower part of the curvature center of the lens face in the nearly central part of a bar-lens. CONSTITUTION:A bar-lens 4 has the following: a lens face 42 covering a whole width of an opening of a reflection frame 3; a curved surface whose radius is sufficiently larger than a radius of the lens face or a nearly flat rear surface 43, composed of a plane, which has been installed at the lower part of th curvature center of the lens face 42, i.e., on the side of a light-emitting diode 2. Accordingly, a light diffusion effect by a refractive index in the rear surface 43 and by a thickness of the bar-lens 4 is obtained at the upper part of the light-emitting diode 2; a condensing property at the upper lens face 42 can be directed to an end edge of an effective irradiation width. In addition, an area of the rear surface 43 of the bar-lens 4 is enlarged; a reference position can be made definite; the light-emitting element 2 can be arranged on one plane. Thereby, an irradiation width is widened; the linear light source becomes rigid and can be handled easily. |
