Focus-invariant presbyopia-correcting phase optics design and optimization

Our research investigates a new approach to presbyopia correction that incorporates phase masking designs into visual optics. Phase masking designs can create degraded PSFs that remain mostly unchanged in the presence of some defocus. These masks can also be tailored to the workings of the human visual system to minimize the impact of the degraded PSFs. This paper covers work done to design a phase masking IOL and to experimentally verify this concept. The IOL design process is carried out in Zemax OpticStudio where custom figures of merit are used to optimize presbyopia correction. For the experimental side of this study, a proof-of-concept PMMA phase plate was created using diamond turning and this optic’s impact on vision was investigated using an artificial eye. This showed that the phase masking design produces acceptable image quality across a range of object distances and pupil sizes.