| 摘要 |
PURPOSE: A micro lithography reduction objective lens is provided to seize a high resolution in a case where an image field is large and a length of a structure object is short, and to realize a correction of an image error related to a distortion. CONSTITUTION: A micro lithography reduction objective lens comprises a first lens group(LG1) of a positive refraction, a second lens group(LG2) of a negative refraction, a third lens group(LG3) of a positive refraction, a fourth lens group(LG4) of a negative refraction and a fifth lens group(LG5) of a positive refraction. A value of an aperture of an image side is over 0.65, and a system iris(AS) is disposed in the fifth lens group(LG5). At least two lenses of the fifth lens group(LG5) are disposed in front of the system iris(AS).
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