Corrective eye wear has a long history and its origins can be found almost as far back as the 13thcentury. From a magnifying lens used to read manuscripts, to the stylish, light weight pieces sitting on our faces that we have today, prescription glasses have come a long way.
Earlier we only had glass being used to make the glasses, however as we advanced with technology we had plastic glasses. Compared to the heavy glass ones these were more durable and lasted longer. The only problem with these kinds of glasses was that, they were prone to scratches and this ultimately affects the visibility. Currently polycarbonate is being used in many eyewears, which is long lasting and durable.
The lenses used in corrective eyewear can be single vision, bifocals, trifocals or multifocals. Convex lenses are used for far sightedness (hyperopia), concave lenses correct near sightedness (myopia) and cylindrical lenses correct astigmatism and presbyopia is corrected using convex lenses and the patients require bifocal eyeglasses. Bioptics are used in cases of severe vision impairment.
Prescription glasses are also used to wear in the sun, to protect the eyes from harmful rays of the sun. These include iridium lens coatings that balance light in the bright sun, polarized lenses that filter out glare and photo chromic lenses that lighten and darken automatically.
Since individual power varies considerably, it is always better to visit an optometrist each time the glasses are changed so that he can customize the glasses according to your needs. A qualified doctor, can determine the kind of lens and the power of the lens that you need, by taking specific tests.
In today’s fast paced world when one cannot afford to waste time travelling and selecting the right kind of eyewear, internet has proved to be boon. Prescription glasses are easily available online and can be purchased with a click of a button. This not only saves your time, but you also have a wider variety of options to choose from.
Although shopping online is easy and one need not worry about fitting in appointments in their busy schedules, it is advisable that people go for periodic eye checkups regularly as eye power tends to fluctuate with age and with certain health conditions. This will not only detect any problems if present, but also grant the fact that the spectacle, that you are wearing, is optimal for your needs.