公开(公告)号：US20040109134A1

公开(公告)日：2004-06-10

申请号：US10685389

申请日：2003-10-16

Applicant: PENTAX Corporation

Inventor： Hiroshi Sato ,  Chikara Yamamoto ,  Moriyasu Shirayanagi

IPC: G02C007/06

CPC classification number: G02C7/063 ,  G02C7/061 ,  G02C7/066 ,  G02C2202/08

Abstract: A progressive power lens belonging to a series of lenses according to the present invention is provided. If a first lens and a second lens randomly chosen from the series of progressive power lenses have a common spherical refractive power Sph nulldiopternull in the distance portions thereof, the Sph is greater than or equal to null1, and a base curve BC1 of the first lens is smaller than a base curve BC2 of the second lens, the first and second lenses satisfy a condition: 1 Wds null ( BC 1 , Sph ) Wns null ( BC 1 , Sph ) Wdt null ( BC 1 , Sph ) Wnt null ( BC 1 , Sph )