Patent ID: 9229204
Filing Date: 2016-01-05
CPC Classification: G02B

Claim Text:
1. A zoom lens comprising sequentially from an object side, a first lens section having a negative refractive power, and a second lens section formed by multiple lens groups and having an overall refractive power that is positive, wherein the first lens section comprises multiple lenses including sequentially from the object side, a first lens that is a spherical lens having a negative refractive power and a second lens that is an aspheric lens having a negative refractive power, the second lens section is configured to include at least one aspheric lens having a negative refractive power, zooming from a wide angle edge to a telephoto edge is performed by varying an interval between the first lens section and the second lens section, or an interval between the first lens section and the second lens section and intervals between the lens groups comprising the second lens section, focusing from infinity to a minimum object distance is performed by moving any one of the lens groups comprising the second lens section, a conditional expression (1) −8.0≦F a conditional expression (2) 2.5≦|100×Δ1/φ1 |≦10.0 is satisfied, where, φ1 is a maximum effective diameter of an image-side surface of the second lens, and Δ1 is a difference of a perimeter edge thickness of an aspheric surface and a perimeter edge thickness of a paraxial spherical surface, on a perimeter of an area demarcated by the maximum effective diameter φ