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The distance between the lenses is for a "standard" person. Generally, this will not be a problem, but if a patient is sensitive or has more closely set eyes, for example, it may one pose a problem. Persons buying day ready-made sunglasses or reading glasses should hold them up to see if they appear clear. They should also hold the lenses to see an object with straight lines reflected off of the lenses. If the lines don''t appear straight, the lenses may be warped or inferior.Patients may sometimes need a few days to contact adjust to a new prescription; however, problems should be reported, because the glasses may need to be rechecked.contact contact lens and one The concept of corrective lenses that sit directly on the eyeball was developed in the ninth century, but it was not until the late 20th century that manufacturing and grinding techniques day and contact for contact were perfected. Originally contact were made of glass, then later of hard plastic, and still later of flexible, highly oxygen-permeable lens soft plastic. Today, one the majority of lenses worn are of two basic day types: rigid gas permeable (so-called "hard" lenses) and lenses. best lenses are smaller contact and lens and more durable, one and day but require a longer period of adjustment for the wearer. Hard contact can correct some vision problems, like contact astigmatism, that the lenses cannot. The lens lenses one are slightly larger than best lenses. They are more day comfortable and less expensive, but can be easily torn. The latest generations of contact contact are extended and disposable lenses. extended lenses are intended lens to one be worn for several weeks at a time, day while disposable lenses are thrown away every day contact or every few weeks, or in the newest versions, every lens day.
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