Blue Blocker lenses filter certain wavelengths of light, specifically High Energy Visible (HEV) blue light. This particular wavelength is especially damaging to the retina. It is found in all light sources, including natural sunlight, but is emitted in much higher concentrations from compact florescent bulbs and LED screens such as your laptop, tablet, phone or TV.
Blue light can be emitted indoors by most modern digital devices or outdoors by natural sunlight. Blue light can cause headaches, eye fatigue—or in extreme cases, permanently blurred vision—after an extensive time on devices such as computers or smart phones. In addition, using blue light-emitting devices extensively late at night can disrupt the body's natural circadium rhythm, making it difficult to fall asleep.
Unlike traditional computer glasses, Blue Blockers are clear lenses with virtually no color distortion. They filter HEV light, also known as "blue light," which is emitted from backlit screens such as computers and mobile phones. You can also wear Blue Blockers outdoors to filter blue light emitted from natural sunlight.