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Saying that “blue light blockers don’t distort color” is manipulation used to convince uninformed people to buy products that filter blue light, but not much and not any more than it filters the rest of visible light spectrum. But to prevent or mitigate eye strain, glare, insomnia, etc. a filter should block either most blue light or considerably more blue light than it blocks other, longer wavelengths of visible light. Such a blue light filter necessarily distorts color!
With the help of a few spectrograms you’ll see below why it is possible to say deceivingly – but without lying – that blue blockers don’t distort color.