| 摘要 |
PURPOSE: To provide an illuminator which is improved in efficiency by constructing the illuminator in a simple constitution using no optical integrator and, at the same time, to provide an exposing device improved in throughput. CONSTITUTION: In an illuminator provided with at least a light source having a prescribed size or light source means which forms the image of the light source and condensing optical system which illuminates an object to be irradiated by condensing a luminous flux from the light source means, the light source means is provided with a light source section 1 which supplies a divergent luminous flux and the condensing optical system is provided with first and second concave mirrors 2 and 3. The mirror 2 is composed of part of a paraboloided cylindrical surface which transforms the divergent luminous flux into a parallel luminous flux in a meridional plane and the mirror 3 is composed of part of a body of rotation having a parabolic toric shape rotated around a reference axis AX1 which crosses an axis AX0 at right angles in the meridional plane symmetrically to a position at a prescribed distance from the vortex of the parabola of the mirror 3. |
