THE ARIZONA BOARD OF REGENTS ON BEHALF OF THE UNIVERSITY OF ARIZONA
发明人:
SCHWIEGERLING, JAMES T.
申请号：
CA2752164
公开号：
CA2752164C
申请日:
2010.02.12
申请国别(地区):
CA
年份:
2017
代理人:
摘要：
A diffractive multifocal lens is disclosed, comprising an optical elementhaving at least one diffractive surface, thesurface profile comprising a plurality of annular concentric zones. Theoptical thickness of the surface profile changes monotonicallywith radius within each zone, while a distinct step in optical thickness atthe junction between adjacent zones defines a stepheight. The step heights for respective zones may differ from one zone toanother periodically so as to tailor diffraction order efficienciesof the optical element. In one example of a trifocal lens, step heightsalternate between two values, the even-numberedstep heights being lower than the odd-numbered step heights. By plotting atopographical representation of the diffraction efficienciesresulting from such a surface profile, step heights may be optimized to directa desired level of light power into thediffraction orders corresponding to near, intermediate, and distance vision,thereby optimizing the performance of the multifocallens.
