Smart Phone Text Is Read Closer to Eye Than Hardcopy
Font size is similar to newspaper print, but needs closer working distances than hardcopy
MONDAY, July 18 (HealthDay News) -- The mean font size of text messages and Web pages on handheld electronic devices is comparable with newspaper print but the mean working distance is closer than the typical near-working distance when viewing hardcopy text, according to a study published in the July issue of Optometry and Vision Science.
Yuliya Bababekova, from the State University of New York College of Optometry in New York City, and colleagues conducted two trials to measure the font size and viewing distance that users adopt when using handheld electronic devices, such as smart phones. In the first study, 129 individuals were asked to show a text message on their smart phone, and the vertical height of a lowercase letter was measured without ascenders and descenders. They were then asked to hold the phone as if they were reading the text, and the distance from the phone to their spectacle plane was measured. In the second study conducted in a similar manner, 100 individuals were asked to view a specific Web page from the Internet on their handheld electronic device.
The investigators found that the mean font size for text messages and Internet viewing was 1.1 M and 0.8 M, respectively, which was comparable with newspaper print. For text messages and Internet viewing, the mean working distance was 36.2 cm and 32.2 cm, respectively, which is closer than the typical near-working distance of 40 cm for adults when viewing hardcopy text.
"Practitioners need to consider the closer distances adopted while viewing material on smart phones when examining patients and prescribing refractive corrections for use at near, as well as when treating patients presenting with asthenopia associated with nearwork," the authors write.