Optical Integrator, Illumination Optical Device, Photolithograph, Photolithography, and Method for Fabricating Device

An optical integrator of a wavefront splitting type comprising a first optical member and a second optical member in an order mentioned from an entrance side of light,

• wherein the first optical member comprises a plurality of first entrance surfaces including a predetermined refractive power in a first direction in a plane perpendicular to the optical axis and substantially no refractive power in a second direction perpendicular to the first direction in the plane perpendicular to the optical axis, and a plurality of first exit surfaces formed so as to correspond to the plurality of first entrance surfaces and including a predetermined refractive power in the first direction and substantially no refractive power in the second direction, and
• wherein the second optical member comprises a plurality of second entrance surfaces formed so as to correspond to the plurality of first entrance surfaces and including a predetermined refractive power in the second direction and substantially no refractive power in the first direction, and a plurality of second exit surfaces formed so as to correspond to the plurality of first entrance surfaces and including a predetermined refractive power in the second direction and substantially no refractive power in the first direction.

An optical integrator of a wavefront splitting type comprising a first optical element, and a second optical element disposed behind the first optical element,

• wherein the first optical element comprises an entrance surface including a predetermined refractive power in a first direction in a plane perpendicular to the optical axis and substantially no refractive power in a second direction perpendicular to the first direction in the plane perpendicular to the optical axis, and an exit surface including a predetermined refractive power in the first direction and substantially no refractive power in the second direction,
• wherein the second optical element comprises an entrance surface including a predetermined refractive power in the second direction and substantially no refractive power in the first direction, and an exit surface including a predetermined refractive power in the second direction and substantially no refractive power in the first direction, and
• wherein at least one of the first optical element and the second optical element comprises a plurality of optical elements.