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PPT has taken a leadership role in the global eyecare industry by addressing the question, “How much blue light to filter?” It developed and received a Chinese patent for the Glare Reduction Factor (GRF) that measures the efficacy of a computer lens to reduce glare.

Press Release updated: Dec 16, 2020 09:59 EST

Photoprotective Technologies (PPT) has been awarded Chinese patent 202010078763.3 for an algorithm it developed to quantify the ability of any computer lens to reduce glare from the blue light emitted by electronic devices.

The patent is significant because there are many computer glasses available that claim glare reduction but do not remove enough of the appropriate blue light spectrum of wavelengths. The PPT algorithm factors in the spectrum of the light source and the eye’s sensitivity.  The GRF gives consumers the ability to make a numerical comparison among different lenses – with a higher GRF being more favorable.

The patent is also significant because of China’s dominance in the world production of eyewear and in its ability, therefore, to implement the GRF into the global eyecare industry.

The GRF is the latest in a series of “Light Protection Factors” developed by PPT.  In 2001, PPT published its EPF (Eye Protection Factor). It also has a patent pending for its MPF (Melatonin Production Factor) that quantifies the ability of any given computer lens to preserve the nighttime production of melatonin, the body’s sleep medicine.

Many near-clear and tinted computer lenses fail to significantly reduce any of the three threats posed by blue light – glare, loss of sleep, and potential eye damage. These algorithms allow the consumer to make a more educated decision when choosing their computer lens.

For more information please contact Cristina Garcia at

Source: PhotoProtective Technologies, Inc.