ZOOM LENS SYSTEM, IMAGING DEVICE AND CAMERA

PROBLEM TO BE SOLVED: To provide a small size zoom lens system, an imaging device and a camera capable of providing a well-balanced wide angle of view at a wide angle end and a high zooming ratio.SOLUTION: The zoom lens system includes, from the object side to the image side in order: a first group of positive lenses; a second group of negative lenses; a third group of positive lenses; and a fourth group of positive lenses. The first group of positive lenses is a cemented lens element of a negative lens element at the object side and a positive lens element at the image side. The fourth group of positive lenses is a single lens element. When zooming, in the zoom lens system, the imaging device and the camera, the first group of positive lenses, the second group of negative lenses, the third group of positive lenses and the fourth group of positive lenses are shifted along the optical axis so that the air intervals between the lens groups change to vary the magnification. The conditions: d≤42.00 and f/f≥6.0 ( d: Abbe number with respect to a d-line of the positive lens element in the first group of positive lenses, f: focal distance of entire system at a telephoto end, f: focal distance of entire system at a wide angle end) are satisfied.