| 摘要 |
PURPOSE:To improve the brightness of a screen face considerably by using the first and the second reflective plate to constitute an overhead projector so that the light which is emitted from a light source in the transverse direction and is not used conventionally at all contributes to projection. CONSTITUTION:The first reflective plate 16 has a diameter longer than the length of a light source 11 and has the section formed into a hyperbolic shape surrounding a light emitting part 12 in the traverse direction, and the front edge of the first reflective plate 16 is placed on the same plane as a condenser lens 14 approximately. This first reflective plate 16 reflects the light, which is emitted from the light emitting part 12 in the traverse direction, and leads it forward. The second reflective plate 18 is placed behind an aperture part 17 of the first reflective plate 16 and has the section formed into a hyperbolic shape having the same pole as the first reflective plate 16, and the circumferential edge of the second reflective plate 18 has a diameter longer than that of the aperture part 17 of the first reflective plate 16 and is formed into a short rectangle. A hole part 19 where a spherical reflective mirror 15 should be arranged is opened in the center of the second reflective plate 18. This second reflective plate 18 leads the light, which is emitted from the light emitting part 12 toward the aperture part 17 of the first reflective plate 16, forward. |
