| 摘要 |
PROBLEM TO BE SOLVED: To provide an apochromat class objective lens for an immersion microscope whose numerical aperture attains about 1.2, and which hardly causes distortion of an image surface and has an intermediate magnification (about 50). SOLUTION: The objective lens OL for the immersion microscope is constituted of a 1st lens group G1, a 2nd lens group G2, a 3rd lens group G3 having a positive refractive power as a whole, a 4th lens group G4 having a positive refractive power as a whole, a 5th lens group G5, a 6th lens group G6, a 7th lens group G7 and an 8th lens group G8 in this order from the object side, and is constituted to satisfy the following conditional expressions (1), (2) and (3) respectively. In the respective conditional expressions, (1) is ¾r<SB>112</SB>¾<2*d<SB>11</SB>, (2) is n<SB>1i</SB>>1.7 and (3) isν<SB>2P</SB>>65,ν<SB>3P</SB>>65,ν<SB>4P</SB>>65,ν<SB>5P</SB>>65 andν<SB>6P</SB>>65. COPYRIGHT: (C)2004,JPO&NCIPI
|
