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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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Classification of ophthalmic lenses 


Several centuries ago, the glass lenses are made of transparent minerals, and the only setting for them served as the metal. The development of science and technology has given impetus to the industry, and over time in optics appeared more and more materials suitable for the manufacture of points. 

As a result, a variety of lenses has reached such a level that the layman has become difficult to understand him. Currently, there are several classifications of spectacle lenses. 

Depending on the number of optical zones of vision correction lenses distinguish afocal, odnofokalnye and mnogofokalnye. Afocal lenses have no optical power, that is not intended for vision correction. They are also called lenses with zero power. The main area of their application - sunglasses and goggles to work on the computer. Odnofokalnye lenses have one zone optical activity, then there is one diopter strength across the surface. Mnogofokalnye lenses have two or more areas of optical action. They are indispensable in cases where necessary to clearly see objects and objects at different distances. In turn mnogofokalnye lenses are divided into transfokalnye, that is, having a smooth transition between the optical zone, and lens with a step transition. 

By spatial homogeneity of vision correction lenses are divided into stigmatic and astigmatic. First differ The spherical surfaces, that is, in each meridian have the same effect of refraction. Astigmatic Lenses has two surfaces - one torus, the other spherical. They have two main sections which are perpendicular to each other and with different strength index. And stigmatic and astigmatic lenses on the principal focus is also divided into positive, that is intended to correct farsightedness, and negative, correcting myopia. 

Depending on the shape of the refracting surfaces, lenses are spherical, aspherical and lenticular. Spherical are those lenses that have two spherical surfaces. We base aspheric surface deviates from spherical form, which makes the lenses thinner and light. The central part of the lenticular lenses has the necessary optical power, and peripheral is its basis, thereby also decreasing the thickness and weight of the lens. 

As the material from which lenses are made, they are divided into organic and mineral. To organic materials is wide variety of polymers, the most common of which is plastic. The main mineral material is glass.