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How to choose sunglasses
Material shall be a primary criterion in choosing sunglasses, because health is more important to the style or image. Glasses not only help protect your eyes from bright sunlight, but also do not allow UV light (only glasses with glass lenses). Just wanted to say that too small glasses (whether glass or plastic) though will look stylish, but will be a poor tool in sun protection.

Sport, recreation and sunglasses
For sports sunglasses special requirements. They not only must reliably protect your eyes from the sun, but have increased strength, to be made of special plastic, not glass, because glass increases the risk of eye injuries. According to statistics, 90% of eye injuries could be prevented if protective eyewear, with nearly half of all injuries occurring in children under 14 years.

How to choose glasses for a child?
In the first year of life, the main indications for correction are aphakia and high myopia. In children under the age of three leading indications for correction of hyperopia is for esotropia. Preschool children (3-7 years) to correct aphakia, congenital myopia and hyperopia are added early acquired myopia and astigmatism. At school age, the leading indication for the correction of myopia is acquired.

How to pick the right rims of the glasses?
New Year - the right moment to change the old, familiar, or start something new. For example, you can radically revise its image, or even just thinking about it. Think we'll start with the principal, and most importantly to us, loved ones, of course, the eyes, and everything associated with them.

What you need to remember when choosing a frame for glasses?
Participation points is a fairly serious procedure. Many people, especially women, are choosing to purchase the frames as a costume or decorations. The frame should be modern, "trendy" and yet have to face, color and styling your hair, and jewelry.

Improving appearance points lenses
Vysokoprelomlyayuschie lenses made of organic materials can significantly improve the appearance of spectacles. Using the lenses of materials with refractive indices from 1.60 to 1.74 can substantially reduce the thickness and weight of lenses and glasses to make a superficially more attractive, even at high degrees of ametropia. Variety vysokoprelomlyayuschih range of lenses in combination with optical coatings, which offer today, many manufacturers, often puts consumers in a quandary: what lens to choose? To make the right decision, we must understand the basic characteristics and features of the lens material with high and superhigh refractive index.

Contact lenses
It is believed that the eyes of the lens blush, "dried" lacrimal gland, eyes acquire a specific shine (not the greedy, not that ravenous), triggered by a myriad of diseases and so on. I wear lenses for more than 4 years. With regard to shine in the eyes and other cosmetic effects of the MCL, then I am with my close friends spent the experiment: one in the eye lens, the other without.

Spectral points or more on computer vision syndrome
American Association of optometric studies published data on the new occupational disease "Computer vision syndrome" - (KSZ). Computer vision syndrome in one form or another is observed in 100% of computer users. His symptoms are familiar to almost everyone who holds the monitor more than 4-5 hours a day. Ophthalmologists note the rapid growth of cases of SGC. For example, in North America with typical complaints of the SGC to the doctors turned to 1992, 10 million people. In 1996 - 15 million people., And in 1998 for 22 million people.

Polarizing eyeglasses. What do they differ from ordinary sunglasses?
Although the cost of those and other quite comparable, but the fishing is desirable polarized glasses. How to check whether the data points polarizing? Very simple. Take two pair, and lean their glasses to each other. You will be able to see through them. I now turn to some points by 90 degrees. If you continue to see through the glass, then the conventional glasses, but if you do not see - that's all right - you are in the hands of polarized eyeglasses. What it does affect fishing?

Sunglasses - Accessory enigma
The bright sun is often the cause of the appearance of wrinkles. On clear summer days, it is impossible to watch without squinting his eyes, especially if it is near sea. Sunlight reflected by water, shine in mercy. The only salvation in the hot, cloudless days are the sunglasses.

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Optical coatings


To date, no self-respecting manufacturer of ophthalmic lenses do not overlook their coverage. It really important, because of the quality and purpose of the coating depends on the health of the eyes of consumers, product quality and respectively, the reputation of the manufacturer. 

World's leading optical companies spend a lot of time and money for research in this area and the development of new and new coatings ensure the comfort of vision. Modern optics most common uses several types of coatings: antireflection, hardeners, hydrophobic and metallized. This is the basic, most effective species, but there are many others, which will be more decorative. Coatings have long been considered mandatory for the points, claiming the status of best quality products. 

When light passes through a lens, part of it absorbed by the material, part is reflected. Reflection of light flux occurs at the boundary two transparent media - air and the lens itself. Naturally, these two media have different refractive index. Light can and reflected from the front and rear surface of the lens. If the reflected rays fall on the retina of the eyeball, it leads to a deterioration of the image object of the eye. To reduce this effect, and should be enlightening coating. He also called anti-reflexive. 

Antireflection coating is a thin layer of special optically transparent substance, which "is wedged between two optical media - air and the lens. As a result a second boundary between the reflection light flux: air -- antireflection layer - lenses. The thickness and properties of the layer, as a rule, such that the light rays reflected from these two boundaries, quench each other due to interference. 

Coatings are applied on both sides of the lenses, and layers can be three or more. This layering reduces reflection of light from the lens to 1%. For comparison: a conventional lens, ie, without cover, the magnitude of the reflection light flux reaches 15%. High-quality antireflection coating significantly improves the visual comfort and visual acuity, eliminates glare and attached lens 
more aesthetic appearance. 

Strengthening coatings - a godsend for lovers of plastic lenses. Any polymer is a softer material than sunglass. Of course, this greatly simplifies its handling, but at the same time reduces the resistance to mechanical damage: scratches, cleavage and so on. To increase the strength of lenses and to extend their use, manufacturers use a liner coating are applied to the surface in vacuum by ion bombardment of oxides of metals - zirconium, titanium, magnesium fluoride. 

Because most modern lenses have antireflection coating, it poses another important producers task - to protect the lens from excessive pollution. The fact that this coating very rapidly becomes dirty, and dirt reduces its efficiency. To protect the lens from "sticking" particles of dust and grease on them causing the hydrophobic coating, which has water-and stain-resistant effect, as well as antistatic properties and reduces zapotevaemost lens surface. 

For people whose type of activity associated with the use of electrical appliances, need additional protection. Each device emits electromagnetic radiation of varying intensity, and it is often extremely detrimental to the preservation of visual acuity. Therefore, many well-known manufacturers of optics made it a rule to apply to the lens metallized coating, capable of neutralize the electromagnetic waves. 

This is interesting:
If the antireflective coating consists of one layer, reducing the reflection of light flux occurs only in a single of the spectrum. Therefore, to cover the entire spectrum of visible light on the lens is applied several layers of coatings - for each part of the range own.