UV protective glasses. Sun abbreviations: SPF, UVA, UVB and UVC

You can't see, hear, or feel ultraviolet radiation, but you can actually feel its effects on your body, including your eyes.

You probably know that excessive ultraviolet exposure increases the risk of skin cancer, and you try to use protective creams. What do you know about protecting your eyes from UV radiation?
Many publications in professional publications are devoted to the study of the effects of ultraviolet radiation on the eyes, and from them, in particular, it follows that long-term exposure to it can cause a number of diseases. In the context of a decrease in the ozone layer of the atmosphere, the need for the correct selection of means of protecting the organs of vision from excess solar radiation, including its ultraviolet component, is extremely urgent.

What is ultraviolet?

Ultraviolet radiation is electromagnetic radiation invisible to the eye, occupying the spectral region between visible and X-ray radiation within the wavelength range of 100-380 nanometers. The entire region of ultraviolet radiation (or UV) is conventionally divided into near (l = 200-380 nm) and far, or vacuum (l = 100-200 nm); Moreover, the latter name is due to the fact that the radiation of this area is strongly absorbed by air and is studied using vacuum spectral instruments.

Rice. 1. Full electromagnetic spectrum of solar radiation

The main source of ultraviolet radiation is the Sun, although some sources of artificial lighting also have an ultraviolet component in their spectrum; in addition, it also occurs during gas welding work. The near range of UV rays, in turn, is divided into three components - UVA, UVB and UVC, which differ in their effect on the human body.

When exposed to living organisms, ultraviolet radiation is absorbed by the upper layers of plant tissue or the skin of humans and animals. Its biological action is based on chemical changes in biopolymer molecules caused both by their direct absorption of radiation quanta and, to a lesser extent, by interaction with the radicals of water and other low-molecular compounds formed during irradiation.

UVC is the shortest wavelength and highest energy ultraviolet radiation with a wavelength range from 200 to 280 nm. Regular exposure of living tissue to this radiation can be quite destructive, but fortunately it is absorbed by the ozone layer of the atmosphere. It should be taken into account that it is this radiation that is generated by bactericidal ultraviolet radiation sources and occurs during welding.

UVB covers the wavelength range from 280 to 315 nm and is medium-energy radiation that is hazardous to human vision. It is UVB rays that contribute to tanning, photokeratitis, and in extreme cases, cause a number of skin diseases. UVB radiation is almost completely absorbed by the cornea, but some of it, in the range of 300-315 nm, can penetrate the internal structures of the eye.

UVA is the longest wavelength and least energetic component of UV radiation with l = 315-380 nm. The cornea absorbs some UVA radiation, but most of it is absorbed by the lens. This is the component that ophthalmologists and optometrists should primarily take into account, because it is the component that penetrates deeper into the eyes than others and is potentially dangerous.

The eyes are exposed to a fairly wide range of UV radiation. Its short-wavelength part is absorbed by the cornea, which can be damaged by prolonged exposure to radiation waves with l = 290-310 nm. As ultraviolet wavelengths increase, the depth of its penetration into the eye increases, and most of this radiation is absorbed by the lens.

The lens of the human eye is an excellent filter created by nature to protect the internal structures of the eye. It absorbs UV radiation in the range of 300 to 400 nm, protecting the retina from exposure to potentially harmful wavelengths. However, with long-term regular exposure to ultraviolet radiation, damage to the lens itself develops; over the years, it becomes yellow-brown, cloudy and, in general, unsuitable for functioning for its intended purpose (that is, cataracts form). In this case, cataract surgery is prescribed.

Light transmission of spectacle lens materials in the UV range.

Eye protection is traditionally done with the use of sunglasses, clips, shields, and hats with visors. The ability of spectacle lenses to filter out potentially dangerous components of the solar spectrum is associated with the phenomena of absorption, polarization or reflection of the radiation flux. Special organic or inorganic materials are introduced into the material of spectacle lenses or applied as coatings to their surface. The degree of protection of spectacle lenses in the UV region cannot be determined visually based on the shade or color of the spectacle lens.

Rice. 2. Ultraviolet spectrum

Although the spectral properties of spectacle lens materials are regularly discussed on the pages of professional publications, including Veko magazine, there are still persistent misconceptions about their transparency in the UV range. These incorrect judgments and ideas are expressed in the opinions of some ophthalmologists and even spill out onto the pages of mass publications. Thus, in the article “Sunglasses can provoke aggressiveness” by consultant ophthalmologist Galina Orlova, published in the St. Petersburg Vedomosti newspaper on May 23, 2002, we read: “Quartz glass does not transmit ultraviolet rays, even if it is not darkened. Therefore, any glasses with glass spectacle lenses will protect your eyes from ultraviolet radiation.” It should be noted that this is absolutely false, since quartz is one of the most transparent materials in the UV range, and quartz cuvettes are widely used to study the spectral properties of substances in the ultraviolet region of the spectrum. In the same place: “Not all plastic eyeglass lenses will protect against ultraviolet radiation.” We can agree with this statement.

In order to finally clarify this issue, let us consider the light transmission of basic optical materials in the ultraviolet region. It is known that the optical properties of substances in the UV region of the spectrum differ significantly from those in the visible region. A characteristic feature is a decrease in transparency with decreasing wavelength, that is, an increase in the absorption coefficient of most materials that are transparent in the visible region. For example, ordinary (non-spectacle) mineral glass is transparent at wavelengths above 320 nm, and materials such as uviol glass, sapphire, magnesium fluoride, quartz, fluorite, lithium fluoride are transparent in the shorter wavelength region [BSE].

Rice. 3. Light transmission of spectacle lenses made of various materials
1 - crown glass; 2, 4 - polycarbonate; 3 - CR-39 with light stabilizer; 5 - CR-39 with a UV absorber in the polymer mass

In order to understand the effectiveness of protection from UV radiation of various optical materials, let us turn to the spectral light transmission curves of some of them. In Fig. the light transmission in the wavelength range from 200 to 400 nm is presented for five spectacle lenses made of various materials: mineral (crown) glass, CR-39 and polycarbonate. As can be seen from the graph (curve 1), most mineral spectacle lenses made of crown glass, depending on the thickness at the center, begin to transmit ultraviolet radiation from wavelengths of 280-295 nm, reaching 80-90% light transmission at a wavelength of 340 nm. At the border of the UV range (380 nm), the light absorption of mineral spectacle lenses is only 9% (see table).

This means that mineral spectacle lenses made from ordinary crown glass are unsuitable for reliable protection against UV radiation unless special additives are added to the batch for glass production. Crown glass spectacle lenses can only be used as sun filters after applying high-quality vacuum coatings.

The light transmission of CR-39 (curve 3) corresponds to the characteristics of traditional plastics that have been used for many years in the production of spectacle lenses. Such spectacle lenses contain a small amount of light stabilizer that prevents photodestruction of the polymer under the influence of ultraviolet radiation and atmospheric oxygen. Traditional spectacle lenses made of CR-39 are transparent to UV radiation from 350 nm (curve 3), and their light absorption at the boundary of the UV range is 55% (see table).

We would like to draw the attention of our readers to how much better traditional plastics are in terms of UV protection compared to mineral glass.

If a special UV absorber is added to the reaction mixture, then the spectacle lens transmits radiation with a wavelength of 400 nm and is an excellent means of protection against ultraviolet radiation (curve 5). Spectacle lenses made of polycarbonate are distinguished by high physical and mechanical properties, but in the absence of UV absorbers they begin to transmit ultraviolet radiation at 290 nm (that is, similar to crown glass), reaching 86% light transmission at the boundary of the UV region (curve 2), which makes them unsuitable for use as a UV protection agent. With the introduction of a UV absorber, spectacle lenses cut off ultraviolet radiation down to 380 nm (curve 4). In table 1 also shows the light transmission values ​​of modern organic spectacle lenses made of various materials - highly refractive and with average refractive index values. All these spectacle lenses transmit light radiation starting only from the edge of the UV range - 380 nm, and reach 90% light transmission at 400 nm.

It must be taken into account that a number of characteristics of spectacle lenses and design features of frames affect the effectiveness of their use as means of UV protection. The degree of protection increases with increasing area of ​​spectacle lenses - for example, a spectacle lens with an area of ​​13 cm2 provides 60-65% degree of protection, and with an area of ​​20 cm2 - 96% or even more. This occurs by reducing side illumination and the possibility of UV radiation entering the eyes due to diffraction at the edges of spectacle lenses. The presence of side shields and wide temples, as well as the choice of a more curved frame shape that matches the curvature of the face, also contribute to increasing the protective properties of glasses. You should be aware that the degree of protection decreases with increasing vertex distance, since the possibility of rays penetrating under the frame and, accordingly, getting into the eyes increases.

Cutting limit

If the cutoff of the ultraviolet region corresponds to a wavelength of 380 nm (that is, light transmission at this wavelength is no more than 1%), then why do many branded sunglasses and spectacle lenses indicate a cutoff of up to 400 nm? Some experts argue that this is a marketing technique, since providing protection above the minimum requirements is more popular with buyers, and the “round” number 400 is remembered better than 380. At the same time, data has appeared in the literature about the potentially dangerous effects of light in the blue visible region spectrum to the eye, which is why some manufacturers have set a slightly larger limit of 400 nm. However, you can rest assured that 380 nm protection will provide you with sufficient UV protection to meet today's standards.

I would like to believe that we have finally convinced everyone that ordinary mineral spectacle lenses, and even more so quartz glass, are significantly inferior to organic lenses in terms of ultraviolet cutting efficiency.

Prepared by Olga Shcherbakova, Veko 7/2002

What is the protection level of sunglasses?
What do you need to know about the light transmission of lenses in sunglasses?
Will cheap sunglasses ruin your vision?

When purchasing sunglasses, people fall into two categories:

• those who are extremely scrupulous in their choice study all the marks and icons on the labels
• and those who buy the glasses they like in the accessories section of any clothing store or supermarket just because the model suits their face or clothes.

We won’t say for now whether there is a single correct approach, but we will tell you what parameters sunglasses have, so that each person can choose what is right for him in this particular situation.

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What do you think is the main function of sunglasses? That’s right, it’s even “indicated” in their name - to protect from the sun. And here is an important nuance! Protection is not just “making sure your eyes don’t squint in the sun,” but “protecting your eyes from exposure to harmful ultraviolet light that is present in the sun’s rays.” And the ideal option for sunglasses is 100% UV blocking. This protection will be provided by glasses with UV400 symbols on the temple (sometimes called the “arm”). The number 400 in the marking means that these glasses block all rays of the ultraviolet spectrum of solar radiation with a wavelength of up to 400 nanometers.

The minimum acceptable value, according to GOST R 51831-2001, is the UV380 marking. It is not recommended to buy glasses with protection below this limit, since they transmit ultraviolet radiation, which can provoke the development of cataracts and retinal diseases.

In the Ochkarik optical salons, all sunglasses have the highest degree of protection, and you can be sure of their impeccable reliability.

LIGHT TRANSMISSION AND DEGREE OF DARKNESS

In addition to the degree of protection from UV rays, there is another important parameter: the category (filter) of light transmission of the lens. Like the first one, it can also be indicated on the temple of the glasses.

If the corresponding marking is not there, it may be indicated in the documentation for the glasses. This is acceptable and is not evidence of counterfeit or poor quality of the product, since Russia does not regulate the place where the light transmission category of glasses should be indicated. In Europe, by the way, there is a corresponding quality standard - EN ISO 12312-1, which requires that the category be indicated on the temple (arm) of glasses. It might look like this:

Let's look at the categories of spectacle lenses:

• 0 category orCat.0 transmits from 100 to 80% of light.

This category includes ordinary glasses “with diopters” and clear lenses, which are made according to a doctor’s prescription and are intended to be worn indoors, at night or in twilight; night glasses for drivers; some sports and snow and wind protection glasses, which are used in the absence of bright light.

• 1 category orCat.1 transmits from 80 to 43% of light.

These are glasses with light lenses for cloudy weather, for wearing in the city in weak sun, for use as an accessory.

• 2nd category orCat.2 transmits from 43 to 18% of light.

These glasses are medium in darkness and should be used in partly cloudy weather, in moderately bright sunny weather, and are suitable for driving.

• 3 category orCat.3 transmits from 18 to 8% of light.

Strongly darkened glasses that protect from bright light, including sunlight. Suitable for drivers.

• 4th category orCat.4 transmits from 8 to 3% of light.

The darkest lenses in these glasses allow them to be used in conditions of blinding light (from the sun, snow, water): at sea, in the mountains, in snowy regions, etc. Not recommended for driving as they may make it difficult to determine traffic light colors.

There are also glasses that transmit less than 3% of light - these are special glasses, for example, welding or arctic glasses. They do not belong to any category, are created for special conditions and are not sold in regular optics.

The degree of darkness is the reciprocal of the light transmission category. That is, if the glasses transmit 30% of the light, then they are 70% darkened. And vice versa. It is important to keep in mind that the degree of darkness of the lens does not automatically protect the eyes from ultraviolet radiation! Even completely transparent ones from category 0 can have a UV filter. And vice versa: dark lenses in glasses, but transmit UV rays.

In our salons, most sunglasses fall into category 3. There are also category 1 club glasses with glasses of different colors: yellow, pink, blue.

WHAT IS THE DIFFERENCE BETWEEN EXPENSIVE SUNGLASSES AND CHEAP ANALOGUES?

Today's technologies make it possible to provide the proper degree of eye protection even in very inexpensive sunglasses. In this case, what explains the price difference?

1. Brand

   ​ Opticians and online stores sell glasses of those brands and brands with which they have contracts (from mass market (brands that the majority can afford) to premium class (high price category). The more famous and popular the brand, the higher maybe its price.

2. Materials

   High-quality, reliable, natural, rare, hypoallergenic or simply difficult-to-process materials are more expensive. Designer and decorated glasses also tend to be more expensive than others.

3. Optics quality

   Good glasses will not have even microscopic and invisible gaps, nicks, cracks and other defects that can significantly reduce the service life of the product, affect its appearance or even cause harm to health. Additional checks and quality control require corresponding costs, which add “weight” to the final price of the product.

WILL CHEAP SUNGLASSES HARM YOUR EYES?

And now the main question that follows from all of the above - can inexpensive sunglasses bought, say, in an underground passage, ruin your eyesight?

ANSWER: The main thing is not where and for how much you buy sunglasses, but what materials they are made of, how reliably and efficiently they are processed, whether they have the qualities necessary for your needs - the required category of light transmission, degree of darkness, and, of course, whether they protect against ultraviolet.

The chief doctor of the Ochkarik chain of optical salons comments on this: “Modern theories of the influence of ultraviolet radiation on vision suggest that ultraviolet radiation provokes the development of cataracts (clouding of the lens) and some diseases of the retina.

High-quality sunglasses can have very dark lenses, but do not have UV protection, that is, they allow harmful radiation into the eye. And it's even worse than if you didn't wear sunglasses at all. Physiologically, in bright light, the pupil narrows, the eye squints, thereby preventing the passage of ultraviolet radiation. And in sunglasses, the pupil is wide, you don’t squint, and meanwhile ultraviolet rays penetrate the eye and gradually cause damage to it, if the glasses don’t have UV400.”

With cheap glasses there is a higher risk that the processing of the materials, primarily the lens itself, will be insufficient (a poorly processed edge may crumble!). That is, microscopic crumbs and particles of materials can get into the eye, and this is dangerous. Frames made from questionable materials will not only not last long, but can also cause allergies or skin irritation.

We are not saying that absolutely all cheap glasses are bad. However, in those places of sale where they cannot demonstrate quality certificates to you, in accordance with the legislation of the Russian Federation, or guarantee their availability, you always take a risk.

SO WHAT ARE THE BEST SUNGLASSES?

There are no best or worst - there are those that are suitable or not suitable for a certain situation. If you plan to be under the scorching sun for a long time and in bright light, for example, at sea or snowboarding, then you need glasses with maximum protection “on all fronts” - both from UV and with maximum darkening. If glasses are needed for a photo shoot or a party, the option of simple glasses is certainly acceptable.

However, we are given one vision for the rest of our lives. We perceive the world primarily with our eyes. We get the most vivid impressions from what we see. And is it worth saving on this... Only you can decide.

By the way, in the Ochkarik optics salons you can check the degree of ultraviolet protection of your glasses, absolutely any glasses - even if you bought them a long time ago and not from us. We really care about our customers, so we do UV testing for free for absolutely everyone!

Come to us and see everything for yourself!

For many people, sunglasses are an everyday accessory that allows them to highlight their style and create the desired look. However, we should not forget that these optical products perform another important function - protecting the eyes from exposure to ultraviolet radiation. Let's consider what determines the degree of blocking of UV radiation in sunglasses.

Currently, the ophthalmic products market offers a wide selection of sunglasses. The assortment is replete with popular brands, a variety of shapes, designs and colors. However, when purchasing eyeglasses, you need to take into account not only the decorative component, but also the protective properties of the lenses. It is important that the correction product provides the necessary level of protection of the visual organs from the harmful effects of ultraviolet rays.

Many people are interested in how to choose sunglasses based on the type of protection. We suggest you look into this issue.

Should you protect your eyes from ultraviolet radiation?

To understand whether it is worth protecting your eyes from exposure to sunlight, you need to understand their types, the nature of their occurrence and the impact on the human visual organs. Up to 40% of radiation is classified as visible and allows us to distinguish colors. About 50% of the sun's rays are infrared. They allow you to feel warmth. Finally, 10% of the sun's rays are ultraviolet radiation, which is invisible to human eyes. According to the wavelength, it is divided into several subcategories (long wavelength - UVA, medium wavelength - UVB, and short wavelength - UVC).

Types of ultraviolet radiation:

• UVA - is in the range of 400-315 nm. Mainly reaches the surface of the Earth;
• UVB - is in the range of 315-280 nm. Mainly retained by the atmosphere, but partially reaches the Earth's surface;
• UVC - is in the range of 280-100 nm. It practically does not reach the surface of the Earth (it is retained by the ozone layer).

Do you need glasses to protect your eyes from UV rays?

Ophthalmologists say that in moderate quantities, ultraviolet light is beneficial for the body, as it helps strengthen the immune system, improve body tone and even improve mood. Under the influence of UV rays in the eye, metabolism and blood circulation are stimulated, and muscle function is improved. In addition, the body produces vitamin D, which strengthens the musculoskeletal system, and produces histamine, a substance that has a vasodilating effect.

However, with intense exposure, ultraviolet rays have a detrimental effect on the body, including the organs of vision. The lens captures long-wave UV radiation, gradually losing transparency and acquiring a yellowish tint. Experts recommend paying due attention to protecting your eyes from ultraviolet radiation, since clouding of the lens leads to the development of such a serious disease as cataracts. In 50% of cases, in the absence of timely treatment, this eye disease causes blindness. The mucous membrane of the eye and cornea absorb mid-wave ultraviolet radiation (UVB), which can significantly damage their structure with intense exposure. Using sun protection accessories avoids this problem.

To make a smart purchase, you need to decide what kind of UV protection your sunglasses should have. This factor should be given primary attention when purchasing these products.

Why you should protect your eyes from intense ultraviolet radiation:

• The lens captures long-wave UV radiation, gradually losing transparency and acquiring a yellowish tint. This can lead to cataracts;
• The cornea absorbs mid-wave ultraviolet radiation (UVB), losing its optical properties.

What kind of protection should sunglasses have?

Many people do not know how to determine the level of protection of sunglasses and mistakenly believe that the darker the lenses, the better they block UV rays. However, it is not. Clear lenses can absorb harmful radiation just as well as dark lenses if a special coating is applied to their surface. Moreover, the pupil under dark lenses dilates, so in the absence of a filter, ultraviolet rays are easily absorbed by the lens.

Products from world-famous brands must have special markings indicating the degree of protection. Spectacle optics marked “UV400” are considered to be of the highest quality. It filters up to 99% of UVA ultraviolet light with a wavelength of up to 400 nm. However, it should be taken into account that when regularly wearing such glasses in the summer, a “mask” is formed on the face, since the skin around the eyes does not tan. Much more common are products labeled UV 380, which filter only 95% of UV rays. Inexpensive products provide blocking of 50% of radiation. All products that capture less than 50% of ultraviolet rays do not protect the eyes from their negative effects. Often they are used only for decorative purposes.

Sometimes there is a marking that indicates the degree of protection from both UVA and UVB rays: “Blocks at least 80% UVB and 55% UVA.” This means that the filter applied to the surface prevents the penetration of up to 80% of UVB rays and up to 55% of UVA rays. Doctors advise choosing products where both indicators are above 50%.

In addition, there is another option for marking glasses:

• Cosmetic. Optical products that block less than 50% of UV radiation. These glasses are not recommended for use on sunny days, as they do not protect the eyes from the sun;
• General - universal products with UV filters that block from 50 to 80% of UV rays. Such glasses can be used for everyday eye protection in the city, at mid-latitudes;
• High UV-protection - models with enhanced UV filters that block almost 99% of ultraviolet radiation. They can be used on a bright sunny day in the mountains, near the water, etc.

How to choose sunglasses based on darkness?

Once you have decided on the degree of protection of your glasses from exposure to ultraviolet radiation, you need to select their level of light transmission, or darkness. This parameter will determine how brightly you can perceive the world around you. Typically, this marking is located on the temple of the glasses and consists of two components: the model name and the darkness rating, for example, “Cat. 3" or "Filter cat. 3".

Classification of sunglasses by darkness:

• Marking (0). These products are almost completely transparent. It transmits from 80 to 100% of visible sunlight. These glasses are recommended for use by athletes when exercising in the absence of bright light.
• Marking (1,2). This optics has light transmission from 43 to 80%, and from 18 to 43% of light, respectively. This is the best option for wearing in low to medium sunlight.
• Marking (3,4). These glasses should be used in very bright sunshine.

In the hot summer, for our latitudes, the optimal choice would be optical products with 2 and 3 degrees of light transmission. For use on summer mornings, as well as in spring and autumn, models with 1-2 degrees of darkening are suitable. Glasses with index 4 are recommended for travelers to wear in extreme conditions, for example, when conquering mountains.

It should be clarified once again that the degree of darkness has nothing to do with protecting the eyes from the adverse effects of ultraviolet rays. This indicator exclusively affects the brightness of image perception and the wearing comfort of optical products.

What other protection could glasses have?

Modern manufacturers of sunglasses make sure that their products are as comfortable, practical and durable as possible to use. Therefore, in addition to an ultraviolet filter, additional coatings are often applied to the surface of products.

• Polarizing filter. Completely blocks glare - rays reflected from horizontal surfaces (water, snowy field, car hood, etc.);
• Anti-glare coating. Cuts off some types of solar glare, increasing comfort of use;
• Mirror coating. As a rule, it is applied to one degree or another on all glasses. Reflects visible sunlight, providing additional comfort to the eye;
• Abrasion resistant coating. Increases the resistance of spectacle lenses to mechanical damage (scratches, cracks, etc.);
• Melanin coating. Apply to the inside of the lens to prevent eye fatigue.
• Gradient coating. Allows you to increase safety while driving. The upper, darker part of the lenses provides good visibility when looking at the road. In turn, the light bottom of the lenses contributes to a good view of the instrument panel.

We recommend that you familiarize yourself with the wide selection of glasses and contact correction products on the website. We offer you high-quality products from world brands at competitive prices. With us you can easily place an order and receive the goods in the shortest possible time!

Why is ultraviolet radiation dangerous? When and how should you protect your eyes from harmful solar radiation? What lenses with a UV filter can you buy in our online store?

We begin to think about protecting our skin from the sun only with the appearance of its bright summer rays. After all, everyone has heard about the harmful effects of ultraviolet radiation on our health and many are familiar with medical “horror stories”: it causes cancer and wrinkles appear faster. Unfortunately it's true. However, not only the skin, but also the eyes should be protected from sunlight, since ultraviolet radiation is also very dangerous for them.

By the way, the position: “I see the bright sun - I remember about ultraviolet protection” is not entirely correct. Because there is a type of ultraviolet rays that is active at any time of the year: UVA (spectrum A rays). And yes, even in the harsh Russian winter, when you can’t see the sun at all for 3/4 days, and even on cloudy autumn days.

Tags contact lenses

Ultraviolet rays are electromagnetic radiation in the spectrum between visible and invisible X-ray radiation, the main source of which for people is the Sun. They come in three ranges, determined by wavelength:

• near - UVA
• medium - UVB
• distant - UVC.

Spectrum A and B rays pose a direct threat to people, since C rays do not reach the Earth's surface and are absorbed in the atmosphere. Excess ultraviolet radiation causes burns of varying degrees, cancer, and premature aging of the skin. It is dangerous for the visual organs with such troubles as:

• lacrimation,
• photophobia,
• and in severe cases - corneal burn and retinal damage.

We wrote more about the effects of ultraviolet radiation on vision in.

HOW TO PROTECT YOUR EYES FROM UV rays

To protect your eyes from solar radiation you can and should use:

• sunglasses
• regular (corrective) glasses with specially coated lenses with UV filters (for example, the Crizal brand has these and other lenses with multifunctional coatings)
• contact lenses with UV filters.

Like sunglasses and creams, contact lenses also have several degrees of protection from UV radiation, which are called classes:

• 99% UVB and 90% UVA are blocked first
• The second class filter protects against 95% UVB and 50% UVA.

On packages of contact lenses with a UV filter there is a corresponding mark, usually without indicating the class. If necessary, precise information about the lens protection class can be obtained from the manufacturer.

I would like to note that contact lenses with sun protection are not a complete replacement for sunglasses, but an excellent addition to them. After all, lenses do not protect the area around the eyes, do not save from blinding glare and do not increase the contrast of vision, as, for example, polarized glasses do.

Absolutely all ACUVUE® brand contact lenses from Johnson & Johnson contain UV filters - no other brand can boast such a “breadth” of sun protection across its entire product line. Let's look at a few examples.

Contact lenses 1-DAY ACUVUE® TruEye® - These are soft contact lenses made of silicone hydrogel, a reliable and high-quality modern material. Research results have shown that ACUVUE® TruEye® lenses do not affect the health of your eyes: the condition of your eyes remains exactly the same as before you started wearing the lenses. [I]

They are great for constant wear throughout, even the longest, day. A fruitful work schedule, then playing sports in the gym or jogging in nature, and then planning to drop by for a party with friends? And are you worried whether your lenses will withstand such a rhythm? 1-DAY ACUVUE® TruEye® - will definitely cope with this task! After all, they were specially created for everyone who prefers an active, vibrant and interesting lifestyle.

In addition to the moisturizing component that will prevent your eyes from experiencing discomfort and a feeling of dryness, ACUVUE® TruEye® lenses have maximum protection against ultraviolet radiation - class 1 filters. Accordingly, they block 99% of UVB rays and block 90% of UVA rays.

The replacement period for these lenses is 1 day. That is, you do not need to worry about storing and cleaning them. At the end of the day you just need to throw them away, and in the morning you will take a new pair out of the package!

Lenses ACUVUE® OASYS® And ACUVUE® OASYS® for ASTIGMATISM Designed for two weeks of wear. The unique technology of these lenses - HYDRACLEAR® PLUS - allows you to forget about dryness and keep the lenses moisturized, which means super-comfortable throughout the day. They are suitable for those who spend a lot of time at the computer, with gadgets and in rooms with dry air (for example, in the office). The excellent oxygen permeability of these lenses allows the eyes to breathe freely. A radiant look and constant comfort - what more could you want from lenses?

Of course, safety! ACUVUE® OASYS® and ACUVUE® OASYS® for ASTIGMATISM have a class 1 UV filter, like ACUVUE® TruEye®, i.e. Blocks over 99% UVB and over 90% UVA .

The advantage of these lenses is that they are more economical in price than daily lenses. However, routine replacement lenses require solutions, storage containers and some time to care for them.

Contact lenses are a medical product that comes into contact with the surface of the eye, and their selection should only be carried out by a specialist - an ophthalmologist or an optometrist. Therefore, although the price can be a very tempting argument in favor of purchasing certain lenses, you still need to focus only on the recommendations of your doctor.

These are beauty lenses for those who do not seek compromises between health and beauty! By highlighting the natural color of your iris with their design, they make your image brighter, your gaze more expressive, and you more confident! However, ACUVUE® DEFINE® lenses should not be confused with colored lenses, because they do not completely change the color of your eyes. There are 2 versions of these lenses on the market: with a brown tint and with a blue tint. The manufacturer states that the lenses are suitable for owners of both light and dark eyes.

In addition to charm and comfort, 1-DAY ACUVUE® DEFINE® contact lenses will also provide you with protection from harmful sun rays, thanks to the presence of a class 1 UV filter. The replacement period is 1 day, which adds points to the convenience and comfort of these lenses.

Contact lenses 1-DAY ACUVUE® MOIST® and 1-DAY ACUVUE® MOIST® for ASTIGMATISM also have sun filters. They block 95% of UVB and more than 50% of UVA rays, because... belong to the 2nd class of protection.

Contact lenses from another manufacturer, BAUSCH + LOMB, are another one-day lenses that will protect your eyes from harmful sun rays - UVA and UVB. They are made of an innovative material - HyperGelTM, combining the advantages of both hydrogel and silicone hydrogel lenses. Excellent oxygen permeability, high moisture content, High DefinitionTM high-definition optics - everything in them is created to make you feel in these lenses as if they are not even there before your eyes! 16 hours of excellent vision and comfort - that's what the manufacturer promises us.

You can choose the right sun contact lenses for you in our Ochkarik optics stores. To avoid waiting, we recommend making an appointment with a medical specialist in advance.

When writing this article, materials from the following sites were used: jjvc.ru, acuvue.ru, marieclaire.ru, gismeteo.ru, ru.wikipedia.org, bausch.ru.

[I] D. Ruston, K. Moody, T. Henderson, S. Dunn. Daily contact lenses: silicone hydrogel or hydrogel? Optichen, 07/01/2011. Pages 14-17.

Koch et al. Eyes and contact lenses. 2008;34(2): 100-105. Influence of internal wetting components of contact lenses on higher order aberrations.

Brennan N., Morgan P. CLAE. Oxygen consumption was calculated using the Noel Brennan method. 2009; 32(5): 210-254. Almost 100% of oxygen reaches the cornea when wearing lenses during the day, for comparison: this figure is 100% without lenses on the eyes.

What is UV protection of polycarbonate, why is it needed and what types of it exist? It is these rather important issues that we will try to understand today.

Polycarbonate is a fairly hard, elastic and at the same time flexible material. It is used in almost all areas of construction as a translucent material. In fact, it is the strongest material among all polymers.

But polycarbonate, like polymers, has one serious drawback - it is susceptible to ultraviolet radiation. It turns out that under the influence of direct sunlight, it loses its unique abilities, becomes cloudy and becomes very fragile. Material exposed to long-term radiation is very quickly destroyed by hail, wind and even heavy rain.

UV protection polycarbonate

In the early 70s of the last century, almost everyone was faced with the problem of instability of the polycarbonate structure after prolonged exposure to solar radiation. This became problem number one. It was decided to find a way to eliminate this problem.

At the first stage, special ultraviolet stabilizers were produced and added to the primary material – granules. This was the first UV protection for polycarbonate. But this decision turned out to be quite expensive, since the cost of the final product exceeded all expectations. In addition, stabilizers did not provide 100% protection against UV radiation.

As a result, a decision was made to minimize the costs of creating ultraviolet protection for polycarbonate.

In order to avoid such problems, scientists used the developed stabilizer to create a special coating, which was applied in a fine layer to the polycarbonate. It did not transmit ultraviolet radiation and perfectly preserved the polymer from radiation. It was called ultraviolet protection or abbreviated UV protection of polycarbonate.

Types of UV protection of polycarbonate

This layer is applied to the surface of polycarbonate in two ways: spraying and extrusion.

Spraying is perhaps one of the cheapest and most unreliable methods of applying UV protection to polycarbonate. This application is reminiscent of industrial painting and is carried out immediately after the production of polycarbonate sheets. This method has serious drawbacks. First, if you are not careful, this layer is erased. Secondly, over time, this layer begins to peel off and peel off from the surface of the polycarbonate. This is not visible to the naked eye. Third, such a layer is quickly erased by microparticles during heavy winds, rain and snowfall.

Extrusion UV protection of polycarbonate is considered very practical and reliable. With this protection, the layer is applied to the surface using the extrusion method, that is, it is as if the protective layer is being implanted into the surface. This procedure occurs during the manufacture of polycarbonate panels at high temperatures. The layer of this coating is thicker than the previous one and is less susceptible to mechanical damage.

A protective film must be placed on top of the protective layer. It usually comes with brand names and inscriptions of the manufacturing company and it indicates that under the film there is UV protection of polycarbonate, or something like that. On the other side, the polycarbonate is covered with a film without inscriptions. Polycarbonate panels have only one surface with UV protection.

When installing polycarbonate, the side with UV protection should always be installed towards the radiation source, that is, the sun. Often, inexperienced installers, before installing polycarbonate sheets, remove both protective films and, when installing, inadvertently turn the side with UV protection in the opposite direction from the light source. With such an installation, even the highest quality polycarbonate will quickly become unusable, and in a year or two the first hail will turn it into a sieve.

In general, it is advisable to remove protective films after installation of the sheets, this will minimize minor mechanical damage to the surfaces. But still, if there is a need to remove them earlier, be sure to mark the side with UV protection of the polycarbonate with a marker or other method convenient for you.

Practice advice. Be sure to use during installation. If the ends of the cellular polycarbonate are covered with tapes, the expansion and contraction of the polycarbonate will be smooth without sudden jumps. This occurs due to the air gap inside the honeycomb, the principle of a double-glazed window. The air sealed inside the honeycomb cannot quickly heat up or cool down. If the tapes are missing, then with a sharp expansion, for example, when the sun comes out from behind the clouds, microcracks may appear on the UV layer, which will not be visually visible, but the damage from them will be noticeable after a short period of time.

Very interesting fact. Some large polycarbonate manufacturers, such as, use primary granules to produce monolithic and cellular polycarbonate with an admixture of UV stabilizers. The volume of such stabilizers can reach up to 30% of the total volume of granules. Accordingly, such polycarbonate is not cheap, but the quality, as they say, justifies the cost. Such polycarbonates can last up to 25 years.

When choosing polycarbonate, be sure to ensure that the polycarbonate has UV protection. There are manufacturers who produce polycarbonate without UV protection.

Well, today we have discussed what UV protection of polycarbonate is, why it is needed and what types there are. In addition, tips and recommendations for installing polycarbonate were partially given. I hope this information will be useful to you.

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