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:
Jun. 16, 1998
Filed:
Dec. 22, 1995
Seiko Epson Corporation, Tokyo-To, JP;
Abstract
An eyeglass lens of the present invention has a surface which is a refracting surface arranged such that two coordinate axes X and Y are set to contact with the refracting surface at a determined point thereon while directions of the coordinate axes and an XY plane including the two axes are determined, that a perpendicular line is dropped toward the XY plane from an arbitrary point on the refracting surface, and then X, Y coordinates of an intersecting point between the perpendicular line and the XY plane are denoted by x and y, respectively, and the length of the perpendicular line by z, and that a value of z is expressed as follows: ##EQU1## where r.sup.2 =x.sup.2 +y.sup.2 ; C.sub.x, C.sub.y, K.sub.x, K.sub.y, A.sub.n,m,j are constants to define the shape of lens;