Higher resolution displays may benefit avid screen users by reducing accommodative lag. Photo: Christina on Unsplash.

In an effort to determine whether accommodative microfluctuations—a potential factor in asthenopia—are affected by the image resolution of the display type being observed, researchers recently found that the mean accommodative response appears to respond differently depending on the type of display in use. They noted that higher resolution devices showed a reduced lag of accommodation; this may cause a lead of accommodation in myopes for higher resolution display types.

Twenty participants (10 myopes and 10 emmetropes) observed a target on four different displays: paper, smartphone, e-reader and computer screen while their accommodative responses were measured using a continuous recording infrared autorefractor. The researchers analyzed accommodative response and accommodative microfluctuation measures.

Myopes demonstrated a significantly higher mean accommodative response compared with emmetropes across the four displays. A significant difference in the mean accommodative response between the displays with the lowest and highest resolution was found. A higher mean accommodative response was found with higher resolution of the image. 

“This may suggest that image resolution plays a role in symptoms of digital eye strain,” the study authors wrote in their paper. “It may be necessary to consider that non-symptomatic image resolution falls into a range occurring between excessive lags of accommodation with lower resolution and leads of accommodation for higher resolution displays.”