Crizal Prevencia lenses: How they work and where to buy
What is Crizal Prevencia?
Crizal Prevencia is a special preventive eyeglass lens treatment, known to simultaneously block ultraviolet light and filter a portion of blue-violet light. It eliminates reflections from lens surfaces, reduces glare, resists smudges and scratches and repels water and dust. It is quite comprehensive in its scope.
Lenses with Crizal Prevencia coating filter up to 25% of blue-violet light, while allowing beneficial blue light — blue-turquoise light — to pass through.
Blue-violet light and blue-turquoise light
Information surrounding blue light is often confusing and conflicting. It’s important to know that there are different types of blue light — some of which are beneficial.
The light spectrum is made up of different colors, each of which has its own wavelength, measured in nanometers (nm).
Colors on the warm end of the spectrum (red, orange and yellow) have longer wavelengths — approximately 580 to 700 nm — which means they carry less energy. Colors on the cool end of the spectrum (green, blue, indigo and violet) have shorter wavelengths of 400 to 550 nm, that carry higher energy frequencies.
Blue-violet light
Blue-violet light has a wavelength of 415 to 455 nm and is close on the spectrum to ultraviolet (UV) light. Exposure to UV light is responsible for creating sunburns and skin damage that can lead to different skin cancers.
The greatest producer of blue-violet light is sunlight. So, although smartphones, tablets, computers and TVs emit a very small amount, most blue light, even indoors, is from the sun.
During a vision process known as phototransduction — where light hits the rods and cones in the retina and is turned into electrical signals — the eye absorbs greater amounts of blue-violet light than any other kind of light. Blue light can transmit through the cornea and lens within the eye to the back of the retina.
Some researchers have speculated that too much exposure to high-energy, blue-violet light over a person’s lifetime could potentially impact the retina. However, no current studies have mimicked the natural conditions of blue light exposure to a live human eye. Long-term population studies are needed to know for sure, and no definitive research of this kind currently exists.
Blue-turquoise light
If you move away from UV light on the color spectrum and closer to green light, you’ll find blue-turquoise light. It has a wavelength of 465 to 495 nm.
Blue-turquoise light helps your eyes by enhancing your visual acuity, contrast acuity and color vision. It contributes to pupil function, physical and emotional health and circadian rhythm.
Your circadian rhythm controls your wake and sleep cycles, and blue-turquoise light assists in keeping it on track. A balanced circadian rhythm helps maintain your hormonal balance, mood and memory.
SEE RELATED: Blue light glasses test
How Crizal Prevencia lenses work
Crizal Prevencia lenses are the product of collaboration with the Vision Institute in Paris and years of studying photometry, cellular biology and physics. Through this, researchers were able to pinpoint which light on the color spectrum is most harmful to retinal cells and create a clear lens that effectively filters it.
Technology used to achieve this includes Light Scan, which selectively filters 20% of blue-violet light and 100% of UV light. The lenses are also equipped with back surface protection, so wearers aren’t exposed to UV rays reflected from the back surface of the lens.
Finally, Crizal Prevencia lenses are installed with the Eye Protect System — a feature that allows the lens material to absorb light waves rather than the eye itself. When paired with the Light Scan feature, the Eye Protection System can filter an average of 30% of blue-violet light.
In addition to filtering blue light, lenses treated with Crizal Prevencia have an eye-sun protection factor (E-SPF) of 35 — the highest UV protection level in a clear lens. The goal of this comprehensive lens treatment is to reduce exposure to harmful ultraviolet light and filter a portion of blue-violet light.
Where to find Crizal Prevencia lenses
Crizal Prevencia can be applied to most lens shapes, sizes and prescription strengths (including no prescription at all). However, you can only get new lenses with Crizal Prevencia; it cannot be added to existing lenses.
Many eye doctors, within the U.S. and internationally, offer Crizal Prevencia lenses in frames from their personal inventory. This search tool makes it easy to find local eye doctors who carry Crizal Prevencia lenses. You’re also given the option to filter your search to only show doctors who accept your insurance, making it a convenient method for finding a preferred Crizal Prevencia carrier.
Crizal Prevencia Lenses. Essilor. Accessed August 2021.
Crizal Prevencia: Blue light filter lenses. Essilor. Accessed August 2021.
The visible spectrum. Britannica. Accessed August 2021.
Understanding blue light. Retina Today. April 2016.
Phototransduction. Encyclopedia of Neuroscience. 2009.
Pupillary reflex - an overview. The Senses: A Comprehensive Reference. 2008
Essilor lenses - Crizal Prevencia. Essilor. Accessed August 2021.
Page published on Wednesday, September 15, 2021
Page updated on Tuesday, February 20, 2024
Medically reviewed on Sunday, September 26, 2021