| 摘要 |
PROBLEM TO BE SOLVED: To provide a retrofocus type optical system that achieves favorable correction of various aberrations represented by chromatic aberration, is easy to manufacture and has excellent environment tolerance. SOLUTION: When it is assumed that the Abbe constant isνd and partial dispersion ratios areθgd andθgF, a lens or a layer GIT1 satisfying conditionsνd<30,θgd<-3.333×10<SP>-3</SP>×νd+1.40 andθgF<-2.615×10<SP>-3</SP>×νd+0.67 is arranged in the retrofocus type optical system. In the case that the layer is disposed on the front side of an aperture stop S, the layer is designed to have a positive refractive power, and in the case that the layer is disposed on the rear side of the aperture stop, the layer is designed to have a negative refractive power. COPYRIGHT: (C)2006,JPO&NCIPI
|
