The influence of blue-light-filtering lenses on colour perception

Purpose:

To investigate the influence of two different blue-light-filtering lenses on subjective colour perception, using the Farnsworth-Munsell 100 Hue test.

Material and Methods:

Thirty subjects with normal colour vision performed the Farnsworth-Munsell 100 Hue test wearing three pairs of plano spectacle lenses. The total error score was calculated with the “Farnsworth-Munsell Test Scoring Software“. The evaluated test lenses were the “Glacier Blue Shield“ (Shamir) and the “Wellness Protect 15“ (Eschenbach) in addition to the 15% grey tint (Hoya) as a reference lens. The transmission spectra of the lenses were measured beforehand with the spectrometer “Flame-S-UV-VIS-ES“ (“Ocean Optics“).

Results: 

Using the univariate analysis of variance (ANOVA) with repeated measures, no significant difference could be detected in the colour discrimination capability between the reference lens from Hoya and the test lens from Shamir (p>0.05). A significant deterioration was found with the “Wellness Protect 15“ lens from Eschenbach compared to the reference lens from Hoya (p<0.001) and to the test lens from Shamir (p<0.001). In addition, a median disparity of the third box (43–63 of the Hue test) against all the other boxes was noticed for both the test lenses and the reference lens. 
 

Conclusion: 

With the blue-light-filtering anti-reflection coating from Shamir no difference in colour discrimination could be observed in this study. Only a stronger blue-light-filtering lens like “Wellness Protect 15“ leads to a significant deterioration. The closer the colours are in the CIE colour triangle, the bigger the confusion. To test the quality of colours with these lenses the colour rendering index should also be evaluated.