| 摘要 |
PROBLEM TO BE SOLVED: To provide a projection optical system with high performance which has various aberrations, specially, distortion compensated extremely excellently although the system is made telecentric on both the sides while a relatively wide exposure area and a large numerical aperture are secured by meeting specific requirements of the lens constitution of the projection optical system which projects an image of a 1st body on a 2nd body. SOLUTION: This system has a 1st lens group G1 which has positive refracting power, a 2nd lens group G2 which has negative refracting power, a 3rd lens group G3 which has positive refracting power, a 4th lens group G4 which has negative refracting power, a 5th lens group G5 which has positive refracting power, and a 6th lens group G6 which has positive refracting power. Then the requirements of an inequality I of 0.1<f1 /f3 <17, an inequality II of 0.05<f2 /f4 <7, an inequality III of 0.01<f5 /L<0.9, an inequality IV of 0.02<f5 /L<1.6, and an inequality V of 1.1<f2m /f2 <9 are met, where f1 -f6 are the focal lengths of the lens groups G1 -G6 , f2n is the composite focal length of the intermediate lens groups in the 2nd lens group G2 , and L is the distance from a 1st body to a 2nd body. |
