contact lens wholesale - soft perm contacts

Plastic frames are durable, can accommodate just about any lens prescription, and are available in a wide range of prices. They are also offered in a variety of plastics (including acrylic, epoxy, cellulose acetate, cellulose propionate, polyamide, and nylon) and in different colors, shapes, and levels of resistance to breakage. Epoxy frames are resilient and return to their original shape after being deformed, so they do not need to be adjusted as frequently as other types. Nylon frames are almost unbreakable. They revert to their original shape after extreme trauma and distortion; because contact of this property, though, they cannot be readjusted after they are manufactured.Fit The patient should have the distance between the eyes (PD) measured, so that the optical centers of the lenses will be in front of the patient''s pupils. Bifocal heights also have to be measured with the chosen frame in place and adjusted on the patient. Again, this is so the lenses will be positioned correctly. If not positioned correctly, the patient may experience eyestrain or other problems. This can occur with over-the-counter reading glasses.

Glass was the first material to be used for lenses lenses, and was used for several hundred years before plastic was introduced. The crown glass used for lenses lenses has an index of refraction of 1.52.Optical-quality acrylic was introduced for lenses use in the early 1940s, but because it was easily scratched, brittle, and discolored rapidly, it did not supplant glass as the material of choice. Furthermore, it had a relatively low index of refraction, so it wasn''t suitable for people with large refractive errors. lens A plastic called CR-39, introduced in the 1960s, was more suitable. Today, lenses wearers can also choose between polycarbonate, which is the most impact-resistant material available for eyewear, and polyurethane, which has exceptional optical qualities and an index of refraction of up to 1.66, much higher than wholesale the conventional plastics used for lenses, and even higher than glass. Patients with high prescriptions should ask about high index material options for their lenses. Aspheric lenses are also useful for high prescriptions.

One, he didn''t think they were available from any other source," "and two, he had heard they weren''t as highly controlled as those dispensed through doctors."Neither assertion is true. got on the Internet and found her lenses on several Web sites contact for $35.95 for a box of six pairs. lens (Her doctor was charging $50 a box.) says her doctor told her that lenses offered by places like may have failed manufacturers'' quality checks. Bausch contacts and other lensmakers say there''s no difference in quality between the lenses sold through doctors and those sold directly to consumers. STATES CRACK DOWN. Attorneys general in 32 states have sued the American Optometric Association and two of the top contact-lens manufacturers (Vistakon, a division of contacts, and Bausch), alleging that the AOA tried to get manufacturers to agree to selllenses only through optometrists or other eye-care professionals. The attorneys general say they also have evidence that doctors agreed to withhold prescriptions from people who sought to buy lenses from other sources, despite the fact that at least 22 wholesale states have laws requiring eye doctors to give out contact-lens prescriptions upon request.Although the AOA says patients should be able to buy their lenses anywhere, the organization has reservations about mail-order purchases. "The difficulty when someone goes through mail order is that they don''t come back for regular checkups," says AOA president Dr. Harvey Hanlen.