contact lens
contact lens
contact lens
con′tact lens`
n.
| Noun | 1. |  contact lens - a thin curved glass or plastic lens designed to fit over the cornea in order to correct vision or to deliver medication |
| 单词 | contact lens | |||
| 释义 | contact lenscontact lenscontact lenscon′tact lens`n.
contact(ˈkontӕkt) nouncontact lenscontact lens,thin plastic lens worn between the eye and eyelid that may be used instead of eyeglasses. Actors, models, and others wear them for appearance, and athletes use them for safety and convenience. Contact lenses may also be used to correct certain abnormalities of the eye that cannot be corrected by regular glasses. A. E. Fick, a Swiss physician, made the first contact lens in 1887. His heavy glass lenses exerted an uncomfortable pressure on the eyeball, covered the entire eye surface, and were difficult to fit. In 1938, the first plastic contact lens was made by Theodore E. Obrig, using a newly discovered methylmethacrylate plastic, known as Plexiglas or Lucite, that could be molded into the proper shape. The major drawback was that a solution placed between the lens and eye had to be changed every few hours, because the wearer's tears could not circulate beneath the lens. In 1950, the corneal contact lens was introduced. It covered only the cornea of the eye, floated on the tears of the wearer, and could be worn all day without difficulty. Recent improvements include flexible lenses that shorten the initial period of adjustment for the wearer and porous lenses that do not have to be removed each day. Today, contact lenses that "breathe" have become popular. They allow oxygen to get to the cornea, preventing blurred vision due to the corneal exhaustion syndrome.contact lens[′kän‚takt ‚lenz]contact lenscontact lenscon·tact lenscontact lenscontact lensOphthalmology Crystalline ocular lens A transparent soft or rigid device placed directly on the cornea to correct refractory errorscon·tact lens(kon'takt lenz)contact lensAn optical correction worn in contact with the cornea and taking the place of spectacles. Most contact lens wearers are shortsighted (myopic) and enjoy a generally better standard of vision than with glasses. Hard contact lenses are made of acrylic PMMA (poly-methyl-methacrylate or ‘Perspex’) or CAB (cellulose acetate-butyrate) or co-polymers of various plastics. Soft lenses are mostly made of HEMA (hydroxy-ethyl-methacrylate). Hard lenses are always of smaller diameter than the cornea, soft lenses are usually of greater diameter.Patient discussion about contact lensQ. Contact lenses I’m 17 years old girl, and I have glasses since third grade. I never had any real problems with wearing them,. my best friend always encourage me to try contact lenses, but it seems so strange to put something on directly on your eyes- is it safe? How difficult is it to do? Q. My contact lenses get very dry and it hurts. any suggestions? contact lens
Synonyms for contact lens
|
|||
| 随便看 |
|
英语词典包含2567994条英英释义在线翻译词条，基本涵盖了全部常用单词的英英翻译及用法，是英语学习的有利工具。