What coat­ings do you need for your eye­wear?

One of the main con­cerns for any­one who wears glass­es every day is that your cor­rec­tive lens­es will get scratched and ru­ined, which can be a sig­nif­i­cant ex­pense if you have to pay to re­place those lens­es. Just a few decades ago, the risk of drop­ping and break­ing your lens­es into a thou­sand pieces was much greater, giv­en that lens­es used to be made main­ly of glass, which made for beau­ti­ful lens­es, but they were also very frag­ile. Glass has since giv­en way to plas­tic (a.k.a. or­gan­ic) lens­es, which are more durable, but they are more sus­cep­ti­ble to scratch­es. As a re­sult, coat­ings have been de­vel­oped for or­gan­ic lens­es to help in­crease the dura­bil­i­ty of eye­wear. Some of these coat­ings are ap­plied to plas­tic lens­es by de­fault, such as hard­en­ing and anti-re­flec­tion coat­ings, while oth­ers can be added upon re­quest of the op­ti­cian. Let’s take a look at some of the char­ac­ter­is­tics that lens coat­ings can pro­vide:

HARD­EN­ING: Hard coat­ing is ap­plied to the sur­face of or­gan­ic lens­es to im­prove their re­sis­tance to scratch­es and to in­crease their dura­bil­i­ty over time. It is ap­plied by dip­ping the lens in a vat of spe­cial hard­en­ing enam­els of dif­fer­ent re­frac­tive in­dex­es. Al­ter­na­tive­ly, these enam­els may be ap­plied by way of a process known as spin­ning.

ANTI-GLARE: As the name im­plies, an anti-glare coat­ing (also known as anti-re­flec­tive, or “AR”, coat­ing) serves to block re­flec­tion from sources of nat­ur­al, out­door light (sun­light) or ar­ti­fi­cial light (car head­lights, TV and com­put­er screens). When dri­ving, for ex­am­ple, head­light glare is a ma­jor is­sue that can cause un­want­ed re­flec­tion on the in­ner side of the lens, which can in­ter­fere with our vi­sion by way of a phe­nom­e­non known as “ghost­ing”. This glare can be elim­i­nat­ed by ap­ply­ing an anti-re­flec­tive coat­ing, which elim­i­nates re­flec­tion on the sur­face of the lens and al­lows much more light to pass through the lens. In this way, we see more clear­ly and the lens is more trans­par­ent, which also makes it more aes­thet­i­cal­ly pleas­ing. In pro­duc­tion, the anti-glare process in­volves plac­ing a batch of lens­es in a high-vac­u­um cham­ber and then into a spe­cial ma­chine in which the var­i­ous crys­tals of the coat­ing to be ap­plied are va­por­ized.

ANTI-STA­T­IC: As the name im­plies, this coat­ing elim­i­nates sta­t­ic elec­tric­i­ty so that the lens doesn’t at­tract dust par­ti­cles. An anti-sta­t­ic coat­ing is typ­i­cal­ly in­clud­ed as a stan­dard treat­ment.

• WA­TER AND OIL RE­PEL­LENT: Dirt and grime are the worst en­e­mies of our lens­es. There’s noth­ing worse than hav­ing those an­noy­ing smudges on our glass­es. A wa­ter-re­pel­lent coat­ing en­ables both sides of a lens to re­pel wa­ter and oily sub­stances. An oil-re­pel­lent coat­ing en­sures that the sur­faces of the lens are more** re­pel­lent to liq­uids and oily sub­stances**. These coat­ings are par­tic­u­lar­ly rec­om­mend­ed for sit­u­a­tions when you are like­ly to come into con­tact with oily sub­stances, such as in the kitchen, in an op­er­at­ing room, or at a con­struc­tion site.

BLUE BLOCK: In re­cent years, de­mand for blue-light block­ing lens­es has grown ex­po­nen­tial­ly with the in­creas­ing use of elec­tron­ic de­vices. But what is blue light ex­act­ly? It is the por­tion of high-en­er­gy vis­i­ble (HEV) light in the range of 400 to 420 nanome­ters, which can, if not prop­er­ly fil­tered, cause per­ma­nent dam­age to the cornea and to the reti­na. There are lens ma­te­ri­als on the mar­ket that pro­vide blue-light pro­tec­tion on their own (such as our Blue Nat­ur­al, or this pro­tec­tion can be added as a coat­ing (such as our Chro­ma. It goes with­out say­ing that the first so­lu­tion is prefer­able in or­der to avoid the risk of a pro­tec­tive coat­ing be­ing worn away over time. Or­di­nar­i­ly, a blue-block coat­ing is ap­plied to col­or­less lens­es, but it is also known that the sun emits 20 times more HEV blue light, so sun­glass lens­es with UV and HEV pro­tec­tion, such as our No­HEV Light and Dark, are be­com­ing in­creas­ing­ly pop­u­lar.

PHO­TOCHROMIC: A pho­tochromic coat­ing is what en­ables a lens to dark­en in re­sponse to am­bi­ent light­ing con­di­tions. Pho­tochromic lens­es are used a great deal all year round be­cause they adapt to light­ing con­di­tions so that they can be worn in­doors and out, so you don’t have to change glass­es. With our lens­es, you can se­lect from a com­plete­ly trans­par­ent base, such as our Fo­tochro­ma or Tran­si­tions lens­es, or a tint­ed base, with our Fo­to­col­or lens­es.

PO­LAR­IZED: This is an ex­treme­ly pop­u­lar coat­ing for sun­glass­es, es­pe­cial­ly among peo­ple who dri­ve a lot or play sports. And why is that? If you had a choice be­tween your nor­mal vi­sion and crys­tal-clear vi­sion with per­fect con­trast and no glare, which would you choose? Po­lar­ized lens­es are per­fect for min­i­miz­ing glare.

SEA­WA­TER: Used in par­tic­u­lar on sport lens­es, a salt­wa­ter coat­ing pro­tects the lens­es when worn at sea and pro­longs the life of the lens­es.

ANTI-FOG: Who hasn’t want­ed this over these last two years? Wear­ing glass­es with a face mask has been tor­ture for many of us, so anti-fog sprays — or ac­tu­al anti-fog lens coat­ings — have been sell­ing like crazy. But anti-fog coat­ings have been used for years in sports — es­pe­cial­ly in ski­ing and oth­er moun­tain sports — be­cause they keep lens­es from fog­ging up. You should al­ways ask your pre­ferred op­ti­cian to help you pick out the coat­ings that best meet your needs. Here -> all Di­v­el Italia’s Lens Coat­ings Here -> all Di­v­el Italia’s Lens Coat­ings for sun­glass­es