Patent ID: 7031074
Filing Date: 2006-04-18
Classification: G02B

Abstract:
1. A zoom lens comprising: a first group optical system having a positive refracting power; a second group optical system having a negative refracting power; a third group optical system having a positive refracting power; and a diaphragm that moves toward an object side integrally with the third group optical system, wherein the first group optical system, the second group optical system, and the third group optical system are sequentially arranged from the object side toward an image side, at least the first group optical system and the third group optical system moves in such a manner that a distance between the first group optical system and the second group optical system becomes minimum at a short focal-length side, and a distance between the second group optical system and the third group optical system becomes minimum at a long focal-length side, and the third group optical system includes a triplet lens formed by sequentially bonding a negative lens, a positive lens, and a negative lens.