The effect of blue light filter on visual and task performance.

Purpose: This study aimed to determine the effect of the blue light (BL) filter on the different tasks performed on a laptop on a daily basis.

Methods: Forty subjects were required to perform a 45-minute task on the laptop screen with or without the BL filter on two different days. In the first task, subjects were made to watch a video. In the second task, subjects were made to read a passage from the laptop for 3 minutes, and reading speed was calculated. In the third task, subjects were made to enter the data on the laptop. The time taken to fill in the data was recorded. After the completion of the task, questionnaires were administered. Pre- and post-task accommodative tests were performed.

Results: Forty emmetropes with a mean age of 21 ± 2 were recruited. In visual performance, the subjective response showed a significant difference in visual fatigue level with and without the filter. A statistically significant difference was seen in reading speed and data entry during task performance with and without the filter. Pre- and post-task accommodative parameters showed variable responses.

Conclusion: This study showed that the use of a BL filter improves task performance, but subjectively, people experienced more visual fatigue while using the filter.