A 2017 study (2) entitled Short-Wavelength Light-Blocking Eyeglasses Attenuate Symptoms of Eye Fatigue by Lin JB et al set out to investigate if wearing blue light blocking glasses whilst using digital screens experience less visual fatigue and report fewer symptoms of visual discomfort than control subjects who wear glasses with clear lenses.
The subjects performed a computer task lasting two hours and digital eye strain was measured objectively by measuring critical flicker fusion frequency.
The results of the study showed that the change in Critical fusion frequency after the computer task was significantly more positive (i.e., less eye fatigue) in those wearing blue light glasses versus those with no-block (P = 0.027) and low-block (P = 0.008) groups. Moreover, random assignment to the blue light glasses group but not to the low-block group predicted a more positive change in CFF (i.e., less eye fatigue) following the computer task (adjusted β = 2.310; P = 0.002). Additionally, those wearing blue light glasses reported significantly less feeling of pain around/inside the eye (P = 0.0063), less feeling that the eyes were heavy (P = 0.0189), and less feeling that the eyes were itchy (P = 0.0043) following the computer task, when compared to subjects not wearing blue light glasses.
Another 2017 study by Leung et al (3) set out to examine the benefits of blue light glasses. Their study, Blue-Light Filtering Spectacle Lenses: Optical and Clinical Performances showed that blue light blocking glasses lenses reduce phototoxicity by 10.6%–23.6%, without degrading visual performance, and have thus been suggested as an aid for protecting the eyes against the blue light hazard.
A 2016 study (4) published in Molecular Vision investigated the effects of blue light on eye physiology and on the circadian system. It shows that blue light in the range of 460–480 nm is more effective compared to monochromatic light of 555 nm in reducing the production of melatonin and thus phase-shifting the human circadian clock. It also shows that there can be an accumulative effect of blue light exposure in the eye which can cause long terms concerns as well as the short term effects.
A 2020 study (5), published in the journal of applied physiology, on the effects of blue light glasses on sleep and productivity, entitled The effects of blue filtration on sleep and work outcomes by Cristiano Guarana and Christopher Barnes again showed significant improvements in sleep and work outcomes for those wearing blue light glasses versus a placebo group.