Analysis on the applicability of modified mono-vision for OPALs

We analyzed the effect of modified mono-vision prescription on the occupational progressive addition lenses (OPALs) in presbyopia for indoor use as a method to solve the inconvenience caused by the decrease in the intermediate and the near distances' vision when the PALs worn. To analyze the effect, 37 subjects (57.22 ± 5.18 years) were selected who were wearing PALs and had working hours over 6 h per day on average at intermediate and near distances. Entire tests were carried out with regard to three cases: subjects wearing PALs, occupational progressive addition lenses (OPALs), and prescription for modified mono-vision of OPALs. In order to compare visual performance of three cases, our study evaluated corrected visual acuity and subjective satisfaction at far, intermediate and near distances, stereo-acuity and phoria at far and near distances. The results showed that the prescription of modified mono-vision of OPALs could be useful when applied to the clinical practices for prescribing presbyopic correction.