A zoom lens of the negative lead type includes comprises, in order from an object
side, a first lens unit of negative refractive power and a second lens unit of
positive refractive power, variation of magnification being effected by varying
a separation between the first lens unit and the second lens unit, the zoom lens
satisfying the following conditions:
where NL1 and NL2 are numbers of lens elements which constitute the first lens
unit and the second lens unit, respectively.