徠卡鏡頭的商標名字，是以其光圈設計大小而命名．
NOCTILUX: f/1
SUMMILUX: f/1.4
SUMMICRON: f/2
SUMMARIT: f/1.5 and f/2.5
The SUMMARIT was born as LEICA’s fastest lens in 1949, at f/1.5. It was replaced by the SUMMILUX and it now is for f/2.5
ELMARIT: f/2.8
ELMAR: f/4
HEKTOR:
was the name of The Prophet’s dog, and was the name reserved for LEICA’s lowest-performance lenses.
