Patent ID: 8824062

Claim:
A zoom lens consisting of: a first lens group having positive refractive power, and which is fixed during changing magnification; a second lens group having negative refractive power, and which is moved during changing magnification; a third lens group having negative refractive power for correcting a fluctuation of an image plane caused by changing magnification; and a fourth lens group having positive refractive power, and which is fixed during changing magnification, which are in this order from an object side, wherein the first lens group consists of a negative lens and a positive lens group consisting of three or less positive lenses in this order from the object side, and wherein the negative lens in the first lens group has at least an aspherical surface, and at least one of the positive lens or lenses in the first lens group has at least an aspherical surface, and wherein the following formula (1) is satisfied: 0.14 <d 12/ fG 1<0.44 (1), where d 12 is a distance on an optical axis between the negative lens in the first lens group and a positive lens immediately on the image side of the negative lens, and fG 1 is a focal length of the first lens group.