Bifocal lenses are divided into two parts with different focal powers. The upper part of the lens is normally used for distance vision, while the lower part is used for near-vision tasks such as reading. Most people think of bifocals as having a demarcation line, which can be seen pretty easily. However, thanks to the latest advancements in eyewear technology, bifocal lens designs now offer the consumer other shape choices for the near vision correction component of bifocal lenses. The most popular bifocal lenses are still the half moon or flat top segment. But you will also find a “round” near vision correction component segment, or bifocal lenses with the entire bottom half of the lenses that have the near vision correction component. People with presbyopia, which is the deterioration in the ability of the eye's natural lens to expand or contract in order to focus on close up objects often will get bifocal lenses since they need a special lens for reading, but need a different lens for seeing in the distance. Presbyopia is common for many folks over the age of forty-five.
Progressive Replacement Lenses
Progressive lenses eliminate the visible demarcation lines of traditional bifocals and trifocals. They are often referred to as "no-line bifocals." A progressive lens provides a seamless progression of many lens powers for all viewing distances, which is a more natural correction of presbyopia than offered by bifocal or trifocal prescription glasses. Since they offer the most natural vision correction and are the most attractive lens to wear, they are very popular.
Safety Glasses
Safety glasses often need replacement due to harsh working environments. We offer a full selection of safety glasses and safety lenses, but before ordering, you should have a consultation with your doctor to make sure you are getting the best prescription lens for your needs.
Contact Lenses Replacement
We do not sell contact lenses, because that is a completely different business and we prefer to specialize in eyeglass lenses. If you are looking for an intraocular lens, overnight glasses lenses, or contacts following eye surgery, we cannot help you.
Choosing Your Replacement Lens Material
Replacement lenses for your eyeglass frame are available in glass, standard plastic, polycarbonate, and hi-index plastic. It is good to remember that your eyewear lens material determines how well those lenses will perform in everyday situations.
Glass
In the past, eyewear lenses were only made from glass. You can still buy original lenses made from glass. However they are substantially heavier and more expensive than plastic lenses. Glass lenses are optically clearer than plastic, and are extremely scratch resistant. However they are much less impact resistant than plastic glasses even though in accordance with FDA regulations, glass lenses are safety hardened.
Plastic
Fifty percent lighter than glass lenses, standard plastic lenses are the least expensive material from which eyewear lenses are made. However, to provide the high optical quality of standard plastic lenses (CR-39), the result is the trade-off of offering less strength and reduced durability. Because of the reduced durability of plastic lenses, if not properly taken care of, they will become scratched resulting in a loss of some of their visual clarity. We recommend that plastic lenses have a scratch resistant coating applied to them to protect against such damage and are kept in their cases when not in use.
PolycarbonatePolycarbonate lenses are ten times more impact resistant than standard plastic lenses. They are ideal for everyday wear since they are tough, shatterproof or impact resistant, and lightweight. However, due to their flexibility or softness, which makes them so impact resistant, theyneed a scratch-resistant coating to prevent surface scratches. Unlike regular glass lenses, polycarbonate lenses block 100 percent of the sun's UV rays without the need for special UV- blocking lens coatings.