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  2. Progressive lens - Wikipedia

    en.wikipedia.org/wiki/Progressive_lens

    Progressive lenses are corrective lenses used in eyeglasses to correct presbyopia and other disorders of accommodation. They are characterised by a gradient of increasing lens power , added to the wearer's correction for the other refractive errors .

  3. Eyeglass prescription - Wikipedia

    en.wikipedia.org/wiki/Eyeglass_prescription

    An eyeglass prescription is an order written by an eyewear prescriber, such as an optometrist, that specifies the value of all parameters the prescriber has deemed necessary to construct and/or dispense corrective lenses appropriate for a patient.

  4. Aspheric lens - Wikipedia

    en.wikipedia.org/wiki/Aspheric_lens

    An aspheric biconvex lens. An aspheric lens or asphere (often labeled ASPH on eye pieces) is a lens whose surface profiles are not portions of a sphere or cylinder. In photography, a lens assembly that includes an aspheric element is often called an aspherical lens.

  5. Glasses - Wikipedia

    en.wikipedia.org/wiki/Glasses

    Glasses, also known as eyeglasses and spectacles, are vision eyewear with clear or tinted lenses mounted in a frame that holds them in front of a person's eyes, typically utilizing a bridge over the nose and hinged arms, known as temples or temple pieces, that rest over the ears.

  6. Adjustable-focus eyeglasses - Wikipedia

    en.wikipedia.org/wiki/Adjustable-focus_eyeglasses

    Adjustable focus eyeglasses are eyeglasses with an adjustable focal length. They compensate for refractive errors (such as presbyopia) by providing variable focusing, allowing users to adjust them for desired distance or prescription, or both.

  7. Photochromic lens - Wikipedia

    en.wikipedia.org/wiki/Photochromic_lens

    A photochromic eyeglass lens, part of the lens darkened after exposure to sunlight while the other part remained covered. A photochromic lens is an optical lens that darkens on exposure to light of sufficiently high frequency, most commonly ultraviolet (UV) radiation.

  8. Carl Zeiss AG - Wikipedia

    en.wikipedia.org/wiki/Carl_Zeiss_AG

    Corporate history First workshop of Carl Zeiss in the center of Jena, c. 1847 Carl Zeiss Jena (1910) One of the Stasi's cameras with the special SO-3.5.1 (5/17mm) lens developed by Carl Zeiss, a so-called "needle eye lens", for shooting through keyholes or holes down to 1 mm in diameter 2 historical lenses of Carl Zeiss, Nr. 145077 and Nr. 145078, Tessar 1:4,5 F=5,5cm DRP 142294 (produced ...

  9. Visual acuity - Wikipedia

    en.wikipedia.org/wiki/Visual_acuity

    A person's visual acuity is registered documenting the following: whether the test was for distant or near vision, the eye(s) evaluated and whether corrective lenses (i.e. glasses or contact lenses) were used: Distance from the chart D (distant) for the evaluation done at 20 feet (6 m). N (near) for the evaluation done at 15.7 inches (400 mm).

  10. Fisheye lens - Wikipedia

    en.wikipedia.org/wiki/Fisheye_lens

    A fisheye lens is an ultra wide-angle lens that produces strong visual distortion intended to create a wide panoramic or hemispherical image. [4] [5] : 145 Fisheye lenses achieve extremely wide angles of view, well beyond any rectilinear lens.

  11. Optical coating - Wikipedia

    en.wikipedia.org/wiki/Optical_coating

    An optical coating is one or more thin layers of material deposited on an optical component such as a lens, prism or mirror, which alters the way in which the optic reflects and transmits light. These coatings have become a key technology in the field of optics.