To provide a zoom lens which is bright, that is, its f-number is about 1.8 and made compact in size and attaining high functionalities, even though its power is high of about 18 as zoom ratio, and a video camera in which the zoom lens is incorporated.
This zoom lens is equipped with a 1st fixed lens group, which consists of a positive lens, a 2nd lens group at least one or more surfaces of which are aspherical and which performs variable power action, a 3rd fixed lens group at least one or more surfaces of which are aspherical and which possesses a fixed diaphragm and has positive refractive power, and a 4th lens group which moves over the optical axis, so that an image surface fluctuating accompanying the movement of an object set as a subject is kept at a fixed position from a reference surface, in this order starting from the object side, and it satisfies the specified conditional expression.
ISHIGURO KEIZO
ONO SHUSUKE
