Effect of Blue Light Filters on Tear and Contrast Sensitivity in Individuals Using Electronic Devices

OBJECTIVES: To investigate the effect of contact lenses with blue light filters on contrast sensitivity and any alteration in tear quantity and quality. METHODS: This prospective longitudinal pilot study required three visits by each participant. Monocular visual acuity, contrast sensitivity, phenol red thread test, and tear breakup time were measured at each visit. RESULTS: There were significant differences in logarithmic contrast sensitivity between the groups. The breakup time (BUT) was significantly lower after using video display terminals than before (P<0.05). No differences in BUT were found between groups video display terminals and contact lenses having the blue filter (P>0.05). However, higher mean values were observed in the group after video display terminal use with contact lenses having the blue filter than that with standard contact lenses (P>0.05 in both groups). Furthermore, the mean value of phenol red thread test on the group after video display terminal use with contact lenses having the blue filter was lower than the group before its use (P>0.05). CONCLUSION: The results establish a possible relationship between tear stability, improved contrast sensitivity, and the use of a blue filter in contact lenses.