| 摘要 |
<p>Provided is an optical apparatus equipped with a center-shielding type projection optical system comprising a plurality of reflecting mirrors, wherein the shape of a pupil is roughly uniform at each of the points within an effective imaging area, and a good optical performance can be secured. The optical apparatus, which is provided with an optical system comprising a plurality of reflecting mirrors arranged between a first face and a second face, and forms an image of the first face on the second face, is also provided with an iris-diaphragm member for prescribing the external shape of luminous flux, and a shielding section for shielding a portion of the luminous flux. The iris-diaphragm member comprises an inner circumferential edge that has varying heights in the optical-axis direction of the optical system, and the shielding section comprises an outer circumferential edge that has varying heights in the optical-axis direction.</p> |
