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 |
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.
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