The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 07, 1987
Filed:
Feb. 13, 1985
Applicant:
Inventor:
Michael H Freeman, Denbigh, GB;
Assignee:
Pilkington P.E. Limited, , GB;
Attorneys:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G02C / ; G02C / ; G02C / ; A61F / ;
U.S. Cl.
CPC ...
351159 ; 3511 / ; 351161 ; 351172 ; 623-6 ;
Abstract
A contact or spectacle or implant lens has positive diffractive power which introduces negative longitudinal chromatic aberration that more than counteracts, and is preferably greater than twice, the natural positive longitudinal chromatic aberration of the eye. The residual negative longitudinal chromatic aberration enables the eye/brain system to perform tasks by concentrating on the appropriate color component at the different respective distances without need to accommodate.