Large relative aperture telephoto lens system

A large relative aperture ratio telephoto lens system comprising a first converging lens group, a diverging lens group and a second converging lens group, said first converging lens group comprising a first positive lens component, a second positive lens component, a negative lens component and a third positive lens component, said diverging lens group comprising two negative lens components, and said second converging lens group comprising a positive lens component, a negative lens component and a positive lens component;

• wherein at least one of the second and third lens components constituting said first converging lens group is arranged that Abbe's number is larger than 80 and partial dispersion ratio is larger than 0.53, and said first positive lens component and said negative lens component constituting said first converging lens group satisfying the following conditions (1) and (2):
• .nu..sub.1 >80, .theta..sub.1 >0.53 (1)
• .nu..sub.3 <45, .theta..sub.3 <0.575 (2)
• wherein the reference symbols .nu..sub.1 and .theta..sub.1 represent Abbe's number and partial dispersion ratio of the first positive lens component arranged in said first converging lens group, and the reference symbols .nu..sub.3 and .theta..sub.3 designate Abbe's number and partial despersion ratio of the negative lens component arranged in said first converging lens group.