Patent ID: 7079326

Claim:
A zoom lens, comprising: a first group of lenses, a second group of lenses and a third group of lenses which are subsequently arranged from an object side to an image side; said first group of lenses having negative refractive power, said second group of lenses having positive refractive power and said third group of lenses having positive refractive power; and an aperture stop provided at the object side of said second group of lenses, wherein when zooming from a short focal end to a long focal end is carried out, said second group of lenses moves monotonously from the image side to the object side and said first group of lenses moves so as to correct displacement of an image plane position caused in accordance with the zooming, said first group of lenses includes one positive lens and two negative lenses, said second group of lenses includes three positive lenses and one negative lens, and at least the positive lens in said second group of lenses positioned nearest to the image side is a plastic aspheric lens.