Optics: eye examining – vision testing and correcting – Spectacles and eyeglasses – Ophthalmic lenses or blanks
Patent
1975-12-08
1977-10-25
Rubin, David H.
Optics: eye examining, vision testing and correcting
Spectacles and eyeglasses
Ophthalmic lenses or blanks
351169, G02C 706
Patent
active
040553795
ABSTRACT:
A multifocal ophthalmic lens is described on which one refractive surface is formed to provide a plurality of vertically juxtaposed viewing zones each of which has constant dioptric focal power. The constant dioptric focal power in the various zones increases successively from top to bottom of the multifocal ophthalmic lens. The refractive surface in the zones other than the viewing zone having the lowest focal power at the top of the lens is divided into a plurality of laterally disposed areas. In those areas near the periphery of the lens, the lens is provided with an aspheric surface formed from sections of a figure of revolution such that the principal axes of astigmatism lie in vertical and horizontal planes so that a wearer of the multifocal ophthalmic lens continues to perceive horizontal lines as being horizontal and vertical lines as being vertical and unbroken. However, the height of the ledge which exists between the various zones is restricted to a minimum height over the entire width of the lens which may then be blended during the manufacturing process into the adjacent viewing zones such that the dividing lines between the various viewing zones are rendered invisible.
REFERENCES:
patent: 1271356 (1918-07-01), Paige
patent: 1351785 (1920-09-01), Paige
patent: 1588559 (1926-06-01), Tillyer
patent: 2743649 (1956-05-01), Phillips
patent: 2847804 (1958-08-01), Calkins et al.
patent: 2869422 (1959-01-01), Maitenaz
patent: 2878721 (1959-03-01), Kanolt
patent: 3687528 (1972-08-01), Maitenaz
patent: 3711191 (1973-01-01), Tagnon
patent: 3785724 (1974-01-01), Maitenaz
patent: 3910691 (1975-10-01), Maitenaz
American Optical Corporation
Berkenstock, Jr. Howard R.
Rubin David H.
LandOfFree
Multifocal lens does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Multifocal lens, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Multifocal lens will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-120432