A newly designed high performance standard lens to replace the FL50mm f/1.4 (marketed in April, 1965. 6 elements in 5 groups, Gauss type). This new luxury Gauss type lens uses new type of optical glass for four lens elements out of seven elements in six groups. This lens achieves high contrast, sharp resolving power, optimum color balance and sufficient marginal illumination and it is considered as a norm of the following FD series lenses because of such high performance.