Self-controlled focus associated with reduced hyperopic defocus and axial changes

Allowing readers to self-adjust optical focus during near work may reduce hyperopic retinal defocus and short-term ocular changes without compromising reading performance, according to a study.

In the study, 13 near-emmetropic participants completed a 30-minute mobile phone reading task under unrestricted viewing distance while wearing either a self-adjusted eyeglass (SAG) or a plano eyeglass (PE). The devices used sensors to track reading distance and focus changes. Researchers measured refractive error, axial length, and choroidal thickness before and after the task, while also monitoring reading behavior.

Use of the self-adjusted eyeglass significantly reduced hyperopic retinal defocus compared with the plano control. Participants also adopted a longer working distance during reading, though reading speed was unchanged between conditions. These changes were associated with measurable ocular effects, including reduced axial length elongation and a shift in spherical equivalent refraction following the reading task.

Choroidal thickness was significantly associated with dioptric dynamics but not with the type of lens correction.

Reference
Abokyi S, Chun RKM, de Lestrange-Anginieur EAJ. The Potential of Self-Controlled Focus for Myopia Prevention: A Pilot Study Using a Mobile Phone. Transl Vis Sci Technol. 2026;15(3):28. doi: 10.1167/tvst.15.3.28. PMID: 41879419.