Glasses are an important part in correcting human vision. Therefore, the choice of optics should be approached responsibly. First of all, you need to visit an ophthalmologist who will conduct a comprehensive examination and prescribe glasses. After this you can order glasses. In this case, you should take into account the material from which the lenses will be made. After all, now, in addition to glass, organic polymers are used for manufacturing.
Definition of polymer lenses
Polymer spectacle lenses - These are lenses for the manufacture of which transparent organic plastics are used.
More often polymer CR-39 is used. However, most manufacturers assign their own names to polymers.
Every year the popularity of such products is growing and polymer glasses are gradually replacing optics with mineral lenses from the market.
Modern technologies for the eyes - polymer lenses
In the manufacture of organic lenses, In addition to plastic, special additives are used. Depending on the manufacturing method and structure, they are divided into two types: thermoplastics and thermosets. Thermoplastics are manufactured using injection molding. The most common material is polycarbonate. Its popularity is explained by the fact that polycarbonate is characterized by high resistance to mechanical damage.
Most Popular CR-39 belongs to thermosets. According to its characteristics, the material practically no different from glass. By adding other monomeric substances, CR-39 can be given additional properties, e.g. increase the amount of refraction.
The most modern polymer materials are tribrid and tryvex. They combine all the advantages of CR-39 and polycarbonate - have excellent refractive index and are shock resistant.
Pros of polymer lenses
Some believe that polymer optics are inferior in characteristics to mineral optics, for example, they do not have the same transparency. But modern polymers are not inferior to glass in their optical performance.
In addition, plastic products have a number of advantages:
- Light weight. Thanks to this, polymer glasses can be worn for a long time without experiencing discomfort.
- Plastic does not transmit ultraviolet radiation.
- Impact resistance and safety. Plastic can withstand shock loads. This is because plastic is a viscous material. Upon impact, it will not break into several fragments, which avoids possible eye injury.
- They have a high refractive index. This solved the problem of thick products. Organic glasses are thin, light and elegant.
- Plastic can be painted any color. This allows you to produce optics with any design.
Important! In many countries, almost all optics are made with organic lenses. This is due to the safety of this material. Glass glasses are used only by those people for whom they are recommended for medical reasons.
Minuses
The modern material has virtually no disadvantages; polymer optics have low abrasion resistance. If you wear glasses carelessly, they will quickly become covered with scratches.
Types of organic materials for spectacle lenses
Due to the fact that the pace of human life is becoming faster and faster, glasses must meet all the requirements. This led to the use of a large number of different materials for their manufacture.
For the manufacture of organic lenses the following are used:
- Polycarbonate— the material is lightweight, so it is often used for rimless glasses. It has good characteristics of optical refraction and resistance to mechanical damage. The structure of polycarbonate allows the production of very thin lenses.
- CR-39 - This is the most common material. Suitable for making glasses with small diopters. If the diopter value is over + or – 2, then the product will be quite thick.
- Trivex is a modern type of polymer with high optical refractive indexes. In terms of impact resistance, it is not inferior to polycarbonate. At the same time, it is lighter and has higher optical characteristics. It also has excellent resistance to chemicals. Trivex is excellent for making rimless optics.
- MR-10 – a modern improved polymer with the highest refractive index. The material has excellent viscosity and elasticity.Therefore, lenses made from it are flexible and impact-resistant. In terms of impact resistance, it can be compared with polycarbonate. But at the same time it is much lighter and thinner. This explains the popularity of the polymer among leading manufacturers. It is used for the production of both standard and office and progressive glasses.
Glass lenses
Made from glass of inorganic origin. It is obtained from quartz sand. The material allows you to add various substances to it to improve the refractive index. Using compacting substances, you can obtain a product with refractive index 1.9. However, such optics will have quite a lot of weight.
Advantages
The advantages include:
- High abrasion resistance. This increases the service life of the product.
- It is possible to produce a thin lens with a refractive index of 1.9. With a large diopter value, glass lenses will be thinner than those made from polymers.
Flaws
- Low impact resistance. Under rough mechanical influence, glass glasses break into a large number of fragments. This makes them unsafe.
- Weight. Inorganic glasses weigh significantly more than the plastic version.
- Such products cannot be used to make models with rimless frames.
When choosing the most suitable material for making glasses, it is worth assessing the advantages and disadvantages of both glass and plastic. But modern polymer manufacturing technologies make this material more preferable.
Organic optics are not inferior in refraction to mineral optics. At the same time, it has excellent impact resistance; polymer models can replace 3 pairs of glasses. Therefore, such glasses are an ideal choice for children, athletes, motorists and office workers.And the ability to paint the polymer in any color allows you to get not only a high-quality, but also an original product.
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