| 摘要 |
PURPOSE:To uniform the distribution of light quantity extending over the periphery of a projection device from the center thereof and to obtain the high utilizing efficiency of the light quantity. CONSTITUTION:By giving prescribed positional relation obtained by the positions of a halogen lamp 1, a slide film 5 and the pupil of a projection lens 4 and calculation and prescribed curvature and prescribed aspheric surface coefficient to a first Fresnel lens 2 and a second Fresnel lens 3, the slide film 5 is illuminated with the uniform light quantity and light is condensed at the pupil position of the lens 4 by sufficiently minimizing spherical aberration. |
