Eye glasses have been used for many years and there are many different types of lenses that can be used in your eyeglasses. The lens in eyeglasses can be used to protect your eyes as well as correct any vision problems. The earliest forms of glasses include scissor glasses, pince-nez, monocle and the lorgnette. The more modern glasses all have incorporated padding on the nose and temples for comfort.
Traditionally eyeglasses were made of glass but today they can be comprised of synthetic materials that include polycarbonate, CR-39 and plastic. These synthetic materials are very durable and much lighter than traditional glass lenses.
These synthetic materials are being favored over glass because of they are much more difficult to break, have better transmission of light, absorb more UV light, weigh less and are much more difficult to break. Lenses can be shaped in various ways to correct vision issues and some of the newest lenses can even help with higher eye order aberrations.
Today glasses are all scratch resistant and will have several different types of protective coatings. The most common coatings include scratch coatings and anti-reflective coatings. The anti-reflective coating works very well for night vision as it reduces glare. There are hydrophobic coatings that can be used that repel dirt and water so that you can easily clean your glasses. All plastic lenses will have coatings as they are very popular as they are light in weight, protect against UV light and are scratch resistant.
Eyeglasses are able to correct your vision problems as the lense modifies the length the light hits your eyes. This modification of the lens so that the lens in your eye and the eyeglasses lens will allow you to see properly. It is possible to use eyeglasses for farsight, astigmatism and nearsight. Farsighted eyeglasses or reading glasses can be purchased over the counter if you only need a slight vision correction. Those that are nearsighted and have astigmatism will need to have an eye exam and prescription eyeglasses.
Sunglasses can be obtained as prescription or non-prescription lenses. The main purpose of sunglasses is to protect your eyes from very bright light and UV light. The newest types of eyeglasses are photochromatic so that when more UV light hits them they automatically darken to protect your eye. Sunglasses also have light polarization features. This polarization removes glare so that you can see when reflected light and glare might normally be a problem.
Other popular eyeglasses are sunglasses and sunglasses are mainly used to shield the eyes rom bright light and provide protection from UV light. Photochromatic eyeglasses are the newest form of glasses and the lenses will darken in color as the light becomes brighter. So when indoors the lenses are clear but when you go outside on a sunny day they will darken to protect your eyes.
There are many different colors used for sunglass lenses. Some colors such as yellow and brown can be used to improve your vision and others are simply used for aesthetic purposes. It is also possible to get mirror shades to hide your eyes.
No related posts.
Comments on this entry are closed.