Photochromic lenses prescription lenses and no lenses — how they work (reviews, price)
Photochromic lenses, or as they are called, chameleons are unique glasses for spectacles which have an unusual ability to change its color dependent on the degree of illumination of the environment. In the dark or in the house such products do not change color, remaining the usual transparent glasses. On the street in the daytime glasses are darker, and in bright sunlight they become the sun that is very dark.
The mechanism of action of such products is quite difficult and interesting. They help protect the eyes from harmful UV exposure in bright light. In the room are glasses just correct vision or are your accessory.
Photochromic lenses: are optical devices?
The principle of operation of these glasses is because they contain components that have photochromic properties. The change in the spatial structure performed under the ultraviolet radiation. If the light does not contain ultraviolet light, the glass remains transparent, performing its usual function.
There are photochromic lenses prescription lenses without diopters. In the first case, glasses correct vision and to select them follows with the help of an ophthalmologist, depending on the quality of work of the visual organs, for properly selected points, in fact, mean a lot. The second case involves the use of such devices as accessories indoors, and sunglasses in bright light.
Photochromic lenses: price products
If you want to purchase photochromic lenses, be aware that their value can be completely different. It depends on the quality of the glass, material of manufacture, their functions and properties. They are organic and mineral, prescription lenses, and without them, with different degrees of possible dimmable with many other parameters.
You can find these glasses for 500 rubles apiece, it’s the cheapest counterparts, which can work as described above, the full coping with their tasks. In the salons of optics options presented in the amount of about 1500 rubles per unit, but there is glass and for 6000 rubles apiece. The difference between them is significant. For example, the cheaper options may not fully darken in bright light, or to acquire a clear view of the room, remaining a bit dark.
Early function points depended on the ambient air. And the warmer, the worse was the shading. This means that coming summer day outside, sunglasses were darkened very slowly. But modern technology has virtually eliminated such a disadvantage, and now functions optical data items are not dependent on external factors. But the cost of such lenses considerable.
Important! The higher the value of the products, the better they will perform their functions.
Clearly and in detail about photochromic lenses in the following video:
The efficiency of correction
Today is very popular photochromic lenses, reviews the evidence for them is about the effective protection from ultraviolet radiation and the simultaneous possibility to adjust the vision. Besides, products can be purchased and other required properties when applied to them multifunctional coating.
As a rule, the blackout only occurs outdoors and in car glasses remain transparent, but today there are models that allow to detain and shortwave radiation, protecting the eye and when driving. They are shown to people with poor eyesight, who have to order the sunglasses with prescription lenses. In this case, these two properties combined in a single product.
You will be able to choose any design and frame for such correction. It can be a progressive model, traditional, or monofocal aspherical variations. You can choose any refractive index, or to give them greater finesse.
Such products are shown to people suffering from such diseases:
- degenerative impairment of the function of the retina;
- increased lacrimation.
When purchasing photochromic options, you acquire universal glasses that perform all the functions you need. They protect from sun exposure, adjust the eyes, have additional properties, as prevention of diseases, and can be used as an accessory. Today created advanced variations that respond faster to changing lighting, fully protecting the eyes.