Patent ID: 11963868
Assignee: AST PRODUCTS, INC.
Field: Medical technology (Instruments)
Classification: CPC A  G | IPC A

Claim 13:
14. A method of manufacturing the diffractive trifocal lens of claim 1, the method comprising:
(a) manufacturing the first aspheric surface optionally comprising a toric component;
(b) manufacturing the second aspheric surface; and
(c) generating the central zone and the diffractive elements comprising the plurality of concentric annular zones on the second aspheric surface, each concentric annular zone having the periodically structured curve comprising the two smooth turning points between the two sharp turning points, wherein the slope of the periodically structured curve changes sign at each of the two smooth turning points in each of the concentric annular zones,
thereby producing the near focus (f2), the intermediate focus (f1), and the distance focus (f0).