Designing progressive addition lenses (PALs) with the special needs of heavy computer users in mind—rather than using conventional methods of prescribing—helps reduce digital eyestrain symptoms for workers, increases their visual comfort and tolerance, and improves their body posture at the computer. Researchers have found that abandoning the far distance power and lowering the power range effectively decrease the magnitude of unwanted astigmatism, thereby leading to a subjectively perceived larger field of view with specific computer lenses.
A recent crossover study in Germany compared computer-specific PALs with general-purpose ones in 190 presbyopic computer workers. Subjects tested both corrections at their personal workplace for two weeks each, for computer display work only. The preference for computer-specific PALs for their work was found in 84% of participants. Symptoms of computer vision syndrome were seven times more frequent with general-purpose PALs. Presbyopia treatment with progressive addition lens success did not depend on the subject’s ametropia or prior experience with those kinds of lenses.
In a questionnaire assessing comfort, subjects were asked to compare the perceived vision at the display unit only and to disregard adverse effects such as orientation in the room and walking to the printer. Thus, the study’s results are not fully transferrable yet to a daily office routine. Researcher concluded that the high preference of visual display unit workers for specific computer lenses, the lenses’ benefits and the low penetration rate of these lenses on the market, opticians and optometrists should augment their marketing and sales efforts for progressive addition lenses for computer work.
|Kolbe O, Degle S. Presybopic personal computer work: a comparison of progressive additional lenses for general purpose and personal computer work. Opt Vis Sci. 2018; 95(11):1046-53.|