enow.com Web Search

  1. Ads

    related to: vertex contact lens calculator toric chart conversion rate

Search results

  1. Results from the WOW.Com Content Network
  2. Vertex distance - Wikipedia

    en.wikipedia.org/wiki/Vertex_distance

    Vertex distance is the distance between the back surface of a corrective lens, i.e. glasses (spectacles) or contact lenses, and the front of the cornea. Increasing or decreasing the vertex distance changes the optical properties of the system, by moving the focal point forward or backward, effectively changing the power of the lens relative to ...

  3. Eyeglass prescription - Wikipedia

    en.wikipedia.org/wiki/Eyeglass_prescription

    Patients with astigmatism need a cylindrical lens, or more generally a toric lens to see clearly. The geometry of a toric lens focuses light differently in different meridians. A meridian, in this case, is a plane that is incident with the optical axis. For example, a toric lens, when rotated correctly, could focus an object to the image of a ...

  4. Intraocular lens power calculation - Wikipedia

    en.wikipedia.org/wiki/Intraocular_lens_power...

    The aim of an accurate intraocular lens power calculation is to provide an intraocular lens (IOL) that fits the specific needs and desires of the individual patient. The development of better instrumentation for measuring the eye's axial length (AL) and the use of more precise mathematical formulas to perform the appropriate calculations have significantly improved the accuracy with which the ...

  5. Corrective lens - Wikipedia

    en.wikipedia.org/wiki/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.

  6. Toric lens - Wikipedia

    en.wikipedia.org/wiki/Toric_lens

    Toric lens surface as "cap" (top-right) from a torus (here with R = 1.2 r). A toric lens is a lens with different optical power and focal length in two orientations perpendicular to each other. One of the lens surfaces is shaped like a "cap" from a torus (see figure at right), and the other one is usually spherical.

  7. Intraocular lens - Wikipedia

    en.wikipedia.org/wiki/Intraocular_lens

    Like toric contact lenses, toric IOLs have different powers in different meridians of the lens, and they must be positioned on the correct meridian to reverse the preexisting astigmatism. If the toric IOL is not on the correct meridian, it may need to be repositioned in a second procedure. [22]

  1. Ads

    related to: vertex contact lens calculator toric chart conversion rate