A study involving normal participants found no observed difference in sleep quality .
We found no studies investigating effects on macular structure or function .
We find a lack of high quality evidence to support using BB spectacle lenses for the general population to improve visual performance or sleep quality , alleviate eye fatigue or conserve macular health
PURPOSE Blue-blocking ( BB ) spectacle lenses , which attenuate short-wavelength light , are being marketed to alleviate eyestrain and discomfort when using digital devices , improve sleep quality and potentially confer protection from retinal phototoxicity .
The aim of this review was to investigate the relative benefits and potential harms of these lenses .
Blue-Light Filtering Spectacle Lenses: Optical and Clinical Performances
Purpose s To evaluate the optical performance of blue-light filtering spectacle lenses and investigate whether a reduction in blue light transmission affects visual performance and sleep quality . Methods Experiment 1 : The relative changes in phototoxicity , scotopic sensitivity , and melatonin suppression of five blue-light filtering plano spectacle lenses  were calculated based on their spectral transmittances measured by a spectrophotometer . Experiment 2 : A pseudo-r and omized controlled study was conducted to evaluate the clinical performance of two blue-light filtering spectacle lenses ( BF : blue-filtering anti-reflection coating ; BT : brown-tinted ) with a regular clear lens ( AR ) serving as a control . A total of eighty computer users were recruited from two age cohorts ( young adults : 18–30 yrs , middle-aged adults : 40–55 yrs ) .  Contrast sensitivity under st and ard and glare conditions , and colour discrimination were measured using st and ard clinical tests . After one month of lens wear , subjective ratings of lens performance were collected by question naire . Results All tested blue-light filtering spectacle lenses theoretically reduced the calculated phototoxicity by 10.6 % to 23.6 % . Although use of the blue-light filters also decreased scotopic sensitivity by 2.4 % to 9.6 % , and melatonin suppression by 5.8 % to 15.0 % , over 70 % of the participants could not detect these optical changes . Our clinical tests revealed no significant decrease in contrast sensitivity either with ( 95 % confidence intervals [ CI ] : AR – BT [ –0.05 , 0.05 ] ; AR – BF [ –0.05 , 0.06 ] ; BT – BF [ –0.06 , 0.06 ] ) or without glare ( 95 % CI : AR – BT [ –0.01 , 0.03 ] ; AR – BF [ –0.01 , 0.03 ] ; BT – BF [ –0.02 , 0.02 ] ) and colour discrimination ( 95 % CI : AR – BT [ –9.07 , 1.02 ] ; AR – BF [ –7.06 , 4.46 ] ; BT – BF [ –3.12 , 8.57 ] ) . Conclusion Blue-light filtering spectacle lenses can partially filter high-energy short-wavelength light without substantially degrading visual performance and sleep quality . These lenses may serve as a supplementary option for protecting the retina from potential blue-light hazard . Trial Registration Clinical Trials.gov
A study involving normal participants found no observed difference in sleep quality .
We found no studies investigating effects on macular structure or function .
We find a lack of high quality evidence to support using BB spectacle lenses for the general population to improve visual performance or sleep quality , alleviate eye fatigue or conserve macular health
PURPOSE Blue-blocking ( BB ) spectacle lenses , which attenuate short-wavelength light , are being marketed to alleviate eyestrain and discomfort when using digital devices , improve sleep quality and potentially confer protection from retinal phototoxicity .
The aim of this review was to investigate the relative benefits and potential harms of these lenses .