Light distribution in diffractive multifocal optics and its optimization.
OBJECTIVE
To expand a geometrical model of diffraction efficiency and its interpretation to the multifocal optic and to introduce formulas for analysis of far and near light distribution and their application to multifocal intraocular lenses (IOLs) and to diffraction efficiency optimization.


METHODS
Medical device consulting firm, Newport Coast, California, USA.


METHODS
Experimental study.


METHODS
Application of a geometrical model to the kinoform (single focus diffractive optical element) was expanded to a multifocal optic to produce analytical definitions of light split between far and near images and light loss to other diffraction orders.


RESULTS
The geometrical model gave a simple interpretation of light split in a diffractive multifocal IOL. An analytical definition of light split between far, near, and light loss was introduced as curve fitting formulas. Several examples of application to common multifocal diffractive IOLs were developed; for example, to light-split change with wavelength. The analytical definition of diffraction efficiency may assist in optimization of multifocal diffractive optics that minimize light loss.


CONCLUSIONS
Formulas for analysis of light split between different foci of multifocal diffractive IOLs are useful in interpreting diffraction efficiency dependence on physical characteristics, such as blaze heights of the diffractive grooves and wavelength of light, as well as for optimizing multifocal diffractive optics.


BACKGROUND
Disclosure is found in the footnotes.
Vision Advancement LLC, Newport Coast, California 92657, USA. vidadv@cox.net
Valdemar
V
Portney
D006801:Humans; D007910:Lenses, Intraocular; D008027:Light; D008433:Mathematics; D049451:Nomograms; D055095:Optics and Photonics; D012029:Refraction, Ocular