The constant development of medical technologies allows millions of people around the world to regain their lost sight and lead a full life. One well-established way to avoid presbyopia, which occurs with age in most people, is to use two or more pairs of glasses. Of course, this is not always convenient, and here bifocal glasses come to the rescue, which combine the properties of two pairs.
Usually, the upper half of the glass in such glasses allows you to see distant objects well, and the lower half allows you to distinguish objects that are nearby. There may be more such glasses in glasses, then bifocal glasses can become trifocal or even multifocal.
The idea of their creation was suggested by nature itself, some varieties of fish have bifocal vision, which allows you to clearly see objects at the bottom of the reservoir and at the same time carefully monitor the approach of birds of prey from above. It is believed that the first bifocal glasses inventedBenjamin Franklin, who combined two pairs of glasses into one.
An interesting development of this idea was proposed by Israeli scientist Zeev Zalevsky, who combined the glasses in such a way that bifocal glasses became much more convenient to use. There is no sharp border between the glasses in his glasses. Light reflected from far and near objects is focused into one continuous stream, which covers the entire retina of the eye. This allows you to see all objects equally well. These glasses are less tired eyes, and it will take less time to adapt to them.
When testing them, an interesting feature was noted. It turned out that they can correct both visual defects. That is, these glasses can not only cope with this age-related ailment, they are also very useful for preventive purposes.
The development of high technologies also provides additional opportunities in the development of the issue of preserving vision. Now bifocal glasses are being developed in their electronic version. In this case, a liquid crystal screen is inserted between the two glasses, which transmits the image to us.
In the case of the electronic version of bifocals, the developers are faced with the task of increasing image quality. Also interesting are the parameters of the novelty to increase or decrease the image, as well as autofocus. The first prototypes are provided by PixelOptics, which continues its research in this area.
After consulting with your doctor, you will be able to purchase bifocal glasses. Their prices vary depending on the company.manufacturer and product quality. But the main thing in this matter is the correctly selected parameters of such glasses. This affects the final adaptation time, which can take up to ten days from the start of use.
If you work more with objects that are located nearby, then the lower glass should be larger than the upper one. And, accordingly, when working with distant objects, buy glasses with a larger area of the upper glasses. This will help you quickly adapt to the new product and lead a fulfilling lifestyle.
