Comunicazione
The impact of smartphone luminance on reading abilities.
Grasso P.A., Gurioli M., Boccardo L.
The use of smartphones has become ubiquitous in our daily lives. A large body of literature is focusing on understanding the effects of their prolonged use while another part is exploiting their popularity to develop more and more reliable remote examination of users' visual habits and ocular health. Here we investigated the impact of different levels of smartphone screen luminance on reading performances. The aim was to depict the relation existing between the use of different levels of luminance and the character size at which participants of different ages and different refractive conditions reach a comfortable level of reading. We developed a smartphone version of the Radner Reading Charts with which participants were tested at three levels of luminance ($i.e.$, 37 cd/m$^2$, 16 cd/m$^2$, 7 cd/m$^2$). Reading acuity and velocity were computed and related with demographic and refractive conditions. Our data show that decreased levels of luminance had a robust impact on reading acuity. As expected, age matters with younger individuals being less affected than older ones. Interestingly we also found a trend towards a larger effect on hyperopic individuals.