| 摘要 |
<p>An illumination optical system, an exposure apparatus, and a device manufacturing method are provided to form various shapes of an effective light source with increased freedom degree in formation of effective light source distribution, and facilitate adjustment of shaping of the effective light source. An illumination optical system for illuminating a target surface by using light emitted from a light source, comprises a prism unit(2), an optical integrator(1), and an optical system. The prism unit refracts the light, comprising a first prism(3a) having a conical concave refractive surface, a second prism(4a) having a pyramidal concave refractive surface, a third prism(3b) having a conical convex refractive surface, and a fourth prism(4b) having a pyramidal convex refractive surface. At least one of the concave refractive surface and the convex refractive surface of the one pair is arranged between the concave refractive surface and the convex refractive surface of the other pair. The optical integrator forms a plurality of light sources with the light emitted from the prism unit. The optical system guides the light emitted from the optical integrator to the target surface.</p> |
