JMIR Publications

ABSTRACT

Background:

Prolonged exposure to computer screens has been associated with visual fatigue and reduced visual comfort, which may in turn affect cognitive performance and concentration. While blue-enriched screen light and display settings are known to influence visual strain, their impact on short-term task performance under different backlight configurations remains insufficiently quantified from a human factors perspective.

Objective:

This study aimed to evaluate the effects of different computer screen backlight settings on user concentration, using typing speed as a quantitative proxy for task performance.

Methods:

A total of 22 adult participants performed standardized reading and typing tasks under different screen backlight conditions, including black text on a white background and white or orange text on a dark background. Screen illuminance and spectral characteristics were measured using a calibrated spectrometer. Typing speed was recorded after controlled reading periods, and statistical analyses were conducted to assess changes in performance across conditions.

Results:

Typing speed decreased significantly after 30 minutes of reading under a traditional black text on white background. In contrast, switching to a dark background with white text resulted in a significant increase in typing speed. Further improvement was observed when orange text was used on a dark background. Myopic diopter showed no significant correlation with changes in typing performance.

Conclusions:

Lower screen illuminance achieved through dark background display settings was associated with improved short-term task performance. These findings suggest that display configurations emphasizing reduced luminance may help maintain concentration during computer-based tasks and have implications for visual ergonomics and human-centered display design. Clinical Trial: Not applicable.