US 11,684,469 B2
Multifocal lens having reduced chromatic aberrations
Myoung-Taek Choi, Arlington, TX (US); Xin Hong, Fort Worth, TX (US); and Yueai Liu, Arlington, TX (US)
Assigned to Alcon Inc., Fribourg (CH)
Filed by Alcon Inc., Fribourg (CH)
Filed on Apr. 6, 2021, as Appl. No. 17/223,268.
Application 17/223,268 is a continuation of application No. 16/541,422, filed on Aug. 15, 2019, granted, now 10,993,798.
Application 16/541,422 is a continuation of application No. 15/363,398, filed on Nov. 29, 2016, granted, now 10,426,599, issued on Oct. 1, 2019.
Prior Publication US 2021/0220118 A1, Jul. 22, 2021
This patent is subject to a terminal disclaimer.
Int. Cl. A61F 2/16 (2006.01); G02C 7/04 (2006.01); G02B 27/58 (2006.01); G02C 7/02 (2006.01); G02C 7/06 (2006.01)
CPC A61F 2/1618 (2013.01) [A61F 2/1654 (2013.01); G02B 27/58 (2013.01); G02C 7/024 (2013.01); G02C 7/041 (2013.01); G02C 7/042 (2013.01); G02C 7/06 (2013.01); A61F 2/1656 (2013.01); G02C 2202/20 (2013.01); G02C 2202/22 (2013.01)] 15 Claims
OG exemplary drawing
 
1. A multifocal ophthalmic lens comprising:
an anterior surface;
a posterior surface; and
a single diffractive structure comprising a plurality of echelettes having a single physical height, the plurality of echelettes having a step height of at least one wavelength and not more than two wavelengths in optical path length, the diffractive structure residing on at least one of the anterior surface and the posterior surface, the diffractive structure providing:
a first diffractive order for a first focus corresponding to a first focal length; and
a second diffractive order for a second focus corresponding to a second focal length, the second focal length being different from the first focal length;
wherein the diffractive structure excludes a 0th diffractive order.