For the purpose of improving or correcting vision
For those people who have problems with their eyesight there are two basic solutions available, that is if eye surgery is not considered. The first is eyeglasses which is still the most common form of eyewear. It is commonly used to improve or to correct a variety of problems which is encountered with vision.
Eyeglasses consists of a frame into which two lenses is fitted which has been specifically customized for that individual based on their eye examination. These eye lenses have one purpose and that is to correct refractive errors.
This might include problems relating to myopia or hyperopia. In the one instance people cannot see objects far away while in the other instance they cannot see things close to the eyes. Most of these problems can be corrected by making use of eyeglasses.
Some people have an irregularly shaped cornea which can cause blurring of the eyesight. As far as contact lenses are concerned they are mostly worn directly on the cornea and just like eyeglasses they will effectively correct refractive errors. This is accomplished simply by subtracting or adding focusing power to the lens and the cornea of the eye.
What does your eye prescription say?
One example of a great online resource where you can learn how to read a prescription and find a good deal on glasses, would be glassesshop.com. When it comes to eyeglasses the power of the lenses is measured in diopters.
This is simply indicating the amount of power which will be required to focus external images directly onto the retina. This is why whenever you look at the typical eyeglass prescription you will notice a couple of interesting abbreviations.
There will be things such as OD better known as Oculus dexterous which will refer to the right eye of a person and quite often the abbreviation RE will be used. There is also OS better known as Oculus sinister which is referring to the left eye of a person and therefore the abbreviation LE is included in that abbreviation.
There will be other measurements included in the eyeglass prescription such as Sphere which is a measurement that is reflecting the amount of nearsightedness or farsightedness which has been encountered.
Another measurement is the Cylinder which will show the amount of astigmatism which is occurring when there is an irregularly shaped cornea which will result in the blurring of eyesight.
Another measurement is the Axis which is used to describe the direction of astigmatism in degrees. When the prescription makes provision for bifocals this is simply adding additional power to the lens. This is why there will be an additional measurement which will be listed on that prescription to show the strength of the additional lens.
What about different eyeglass lenses?
Various kinds of lenses will be used in eyeglasses depending on the specific vision problem from which a person may suffer. There are concave lenses which is simply lenses which is very thin in the center.
This is why the numerical prescription in diopters will always be marked with a minus symbol. These lenses are intended to help people with nearsightedness or myopia. There are also convex lenses which are thickest in the center and therefore they function just like a magnifying glass.
These lenses are prescribed in order to help people who are suffering from hyperopia or farsightedness. This is why the numerical prescription in diopters will always be marked with a plus symbol because these lenses are used to help people who are suffering from farsightedness.
There are also cylindrical lenses which is lenses which is curving more in one direction then in another which is making them suitable to help people suffering from astigmatism.
All of these glasses is available from GlassesShop.com at considerably less than people would expect to pay when going to their optometrist. Purchasing prescription eyeglasses online is becoming increasingly popular because it is so convenient.
Children and eyeglasses
Seeing that a child will have to learn early on to deal with their own eyesight problems, it is advisable to allow them to take an active part in the process of choosing suitable eyeglasses. It will be important to pay attention to a few important details when preparing to obtain new eyeglasses for one of your children.
Technology has made so many things possible such as impact resistant lenses and shatterproof lenses which can be beneficial for those children involved in various kinds of sport. Parents should also consider scratch resistant coating on those lenses in order to prevent unnecessary damage.
Another helpful feature is spring-loaded frames which has been specifically designed not to bend or warp. It is also helpful especially in warmer temperatures to make use of silicone nose pads which will prevent those glasses from slipping.
In the case of very young children especially those under four years of age it can be useful to make use of ear pieces which is able to wrap around the ears. It is also possible to make use of straps in order to keep eyeglasses in place.