Why do we blink?
Short answer
Each blink spreads a thin layer of tears over the surface of the eye. This “tear film” keeps the eye moist, protects it from dust and other irritants, and keeps the surface smooth. It also helps focus light so we can see clearly.
What happens when we read?
Concentrating on reading can reduce how often people blink, whether they read on paper or a screen. So a lower blink rate is not always caused by the screen itself. Some studies found more incomplete blinks—when the eyelids do not close all the way—during screen reading than during print reading. The studies used different tasks, so results can vary by person and situation.