Reduction of the longitudinal chromatic aberration generated by trifocal diffractive IOLs

Session Details

Session Title: Extended-Depth-Of-Focus IOLs II

Session Date/Time: Monday 16/09/2019 | 14:00-16:00

Paper Time: 15:54

Venue: Free Paper Forum: Podium 1

First Author: : D.Gatinel FRANCE

Co Author(s): :    J. Loicq   C. Pagnoulle                          

Abstract Details

Purpose:

To compare on an optical bench longitudinal chromatic aberration (LCA) of Trifocal diffractive IOLs made of either hydrophilic or hydrophobic material, without or without associated innovative technology of LCA reduction.

Setting:

Rothschild Foundation and CEROC, Paris, France

Methods:

The LCA was measured on an optical bench (PMTF, Lambda-X, Nivelles, BE) using the through-focus MTF curves at 480, 546 and 630 nm for diffractive Trifocal IOLs made of either of a hydrophilic or hydrophobic material with and without associated LCA reduction technology. The chromatic defocus (LCA) was approximated for the three focal points from the best focus difference between the MTF peak at 480 nm and at 630 nm. Outcomes will be discussed on the basis of the biomaterial Abbe number and the diffractive pattern features and compared with in vivo measured LCAs of patients implanted with those lenses.

Results:

For diffractive trifocal IOLs without LCA reduction mechanism, the Far focus is shifted towards higher power for the blue light at 480 nm with respect to other wavelengths, while the Near focus is shifted towards lower power, the intermediate focus showing as expected an intermediate behavior. The chromatic defocus is comparatively more pronounced in the case of hydrophobic IOL, as theoretically predicted from a lower Abbe number. When the diffractive pattern is modified with the aim of LCA reduction, it is found that the chromatic of hydrophobic Trifocal IOL displays similar LCA behavior as the hydrophilic trifocal one.

Conclusions:

These outcomes are in line with the in vivo measurements of LCA by patients implanted with those lenses. However, these clinical data must include the contribution of the cornea to LCA for interpretation. It is also shown that it is possible to conceive Trifocal diffractive lenses self-corrected for LCA at some of their foci independently of the nature of the biomaterial and its Abbe number.

Financial Disclosure:

has significant investment interest in a competing company, receives consulting fees, retainer, or contract payments from a competing company, is employed by a for profit company with an interest in the subject of the presentation