With the increasing reliance on tablet computers and smartphones in daily life, it is important to determine whether and how the prolonged usage of these handheld digital devices influences the working habits and refractive status. This study aimed to determine the effects of wearing conventional single-vision lenses vs. new progressive addition lenses on the working distance and refractive status while playing interactive video game in Chinese pre-presbyopic adult computer users.

Chinese adult computer users were recruited from two age cohorts. They were prescribed, in random order, with conventional single-vision lenses and progressive addition lenses designed for handheld digital display devices (iPad). Basic ocular parameters were measured through a comprehensive eye examination at the baseline visit. Working distance and refractive shift were measured immediately after delivering the lenses and after one month of lens wear. Working distance were recorded with an automatic ultrasound sensor while the participants were playing a 30-minute video game. Refractive-error shift before and after playing the video game were measured with an open-field autorefractor in both eyes and averaged.

Inclusion Criteria:

• Hong Kong Chinese
• Computer users (computer usage >2hours/day)
• Spherical-equivalent refractive errors between plano and -9.00D and cylindrical power ≤2.50D

Exclusion Criteria:

• Anyone with visual acuity worse than 0 logMAR, anisometropia more than 2.00D, abnormal accommodative function, wearing rigid contact lens, and a history of ocular surgery and pathology