The invention of contact lenses was such a revolutionary progress in the field of ophthalmic, which is no less than a miracle. Previously, there were immensible problems in this field, which were difficult to manage. It was such a top-level development in correcting refractive problems, which were not only extremely complicated but also too expensive, and majority of people were unable to afford it. As it came in the market, not even a single one who preferred glasses after using these lenses.
In this way, there are few abuses, which were also developed because people began to use lenses without knowing the facts, uses and abuses of lenses. Here it should be noted that old contact lenses need more care, hygiene and they are much more toxic to human eyes. By keeping these abuses of old lenses, manufacturers of lenses began to make lenses, which are less toxic to human eyes, and by which there are less chances to get allergic and they also need less care and hygiene.
You can find several different varieties of lenses made by different companies and come up with different brand names are easily available in the market. You will find either hard or soft lenses when you will go to buy lenses. You should know pre-hand that hard lenses are made up for specific uses and indications. In soft lenses, you can find extended wear, which are worn after some time and need constant cleansing and you need to replace them after some time.
In soft lenses, you can have the option of disposable soft lenses. These lenses also get expire after some time. When you wear contact lenses, you should know that there are daily wear lenses, which are worn for 24 hours. You can also find weekly wear lenses, which can regularly be worn for one week. And there are monthly lenses, which should be used for one month and disposed after one month. You should be aware of cosmetic lenses, which are getting popularity now a day among ladies. They come in different colors and shades.