enow.com Web Search

  1. Ads

    related to: astigmatism contact lenses cost nowadays chart printable blank

Search results

  1. Results from the WOW.Com Content Network
  2. List of soft contact lens materials - Wikipedia

    en.wikipedia.org/wiki/List_of_soft_contact_lens...

    The first contact lenses were made of glass, in 1888. Initially the glass was blown but soon lenses were made by being ground to shape. For the first fifty years, glass was the only material used. The lenses were thin, yet reports of injury were rare. In 1938 perspex (polymethylmethacrylate, or PMMA) began to replace glass in contact lens ...

  3. Astigmatism (optical systems) - Wikipedia

    en.wikipedia.org/wiki/Astigmatism_(optical_systems)

    Astigmatism (optical systems) An optical system with astigmatism is one where rays that propagate in two perpendicular planes have different foci. If an optical system with astigmatism is used to form an image of a cross, the vertical and horizontal lines will be in sharp focus at two different distances. The term comes from the Greek α- (a ...

  4. Contact lens - Wikipedia

    en.wikipedia.org/wiki/Contact_lens

    A pair of contact lenses, positioned with the concave side facing upward. Putting contacts in and taking them out. One-day disposable contact lenses with blue handling tint in blister-pack packaging. Contact lenses, or simply contacts, are thin lenses placed directly on the surface of the eyes. Contact lenses are ocular prosthetic devices used ...

  5. Astigmatism - Wikipedia

    en.wikipedia.org/wiki/Astigmatism

    Astigmatism may be corrected with eyeglasses, contact lenses, or refractive surgery. [1] Glasses are the simplest and safest, although contact lenses can provide a wider field of vision . Refractive surgery can eliminate the need to wear corrective lenses altogether by permanently changing the shape of the eye but, like all elective surgery ...

  6. Effects of long-term contact lens wear on the cornea - Wikipedia

    en.wikipedia.org/wiki/Effects_of_long-term...

    Long-term contact lens use can lead to alterations in corneal thickness, stromal thickness, curvature, corneal sensitivity, cell density, and epithelial oxygen uptake, etc. Other changes may include the formation of epithelial vacuoles and microcysts (containing cellular debris) as well as the emergence of polymegethism in the corneal endothelium.

  7. Corrective lens - Wikipedia

    en.wikipedia.org/wiki/Corrective_lens

    Corrective lens. A pair of contact lenses, positioned with the concave side facing upward. A corrective lens is a transmissive optical device that is worn on the eye to improve visual perception. The most common use is to treat refractive errors: myopia, hypermetropia, astigmatism, and presbyopia.

  1. Ads

    related to: astigmatism contact lenses cost nowadays chart printable blank