To provide a projection optical system which has the focus position less varied and allows a deep focal depth to be secured and to provide an exposure device and a method of forming a circuit pattern which allow a minute pattern to be faithfully and efficiently formed by providing the projection optical system.
A projection optical unit PL1 forms an image on a first surface (where a pattern DP formed on a mask is arranged) on a second surface (the upper face of a plate P). The projection optical unit PL1 has a first concave reflecting mirror 34a and a second concave reflecting mirror 34b which are arranged in a pupillary space thereof, and each of lens groups 33a and 33b arranged in the vicinity of mirrors 34a and 34b is provided with at least one lens which has a high transmittance in order to suppressing the variance of optical characteristics of the projection optical unit PL1.
| WO/2002/035285 | WIDE-ANGLE IMAGING DEVICE |
| JP7103566 | Optical equipment |
| JP2009103944 | OPTICAL SCANNER |
KATO MASANORI
KUMAZAWA MASAHITO
Tadashi Takahashi
Masakazu Aoyama
Kazuya Nishi
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