enow.com Web Search

  1. Ads

    related to: bifocal glasses with prisms

Search results

  1. Results from the WOW.Com Content Network
  2. Multifocal intraocular lens - Wikipedia

    en.wikipedia.org/wiki/Multifocal_intraocular_lens

    Multifocal IOLs: achieve near and distance vision by having two (bifocal) or three (trifocal) focal points simultaneously. The function of multifocal IOL depends on the pupil size for refractive types. The concept is based on the principle that the pupil tends to constrict for near tasks, so the central portion of the lens is designed for near ...

  3. Four prism dioptre reflex test - Wikipedia

    en.wikipedia.org/wiki/Four_prism_dioptre_reflex_test

    Purpose. assess alignment of both eyes. The Four Prism Dioptre Reflex Test (also known as the 4 PRT, or 4 Prism Dioptre Base-out Test) is an objective, non-dissociative test used to prove the alignment of both eyes (i.e. the presence of binocular single vision) by assessing motor fusion. [1] Through the use of a 4 dioptre base out prism ...

  4. History of optics - Wikipedia

    en.wikipedia.org/wiki/History_of_optics

    History of optics. Modern ophthalmic lens making machine. Optics began with the development of lenses by the ancient Egyptians and Mesopotamians, followed by theories on light and vision developed by ancient Greek philosophers, and the development of geometrical optics in the Greco-Roman world. The word optics is derived from the Greek term ...

  5. Pinhole glasses - Wikipedia

    en.wikipedia.org/wiki/Pinhole_glasses

    Pinhole glasses, also known as stenopeic glasses, are eyeglasses with a series of pinhole-sized perforations filling an opaque sheet of plastic in place of each lens. Similar to the workings of a pinhole camera, each perforation allows only a very narrow beam of light to enter the eye which reduces the size of the circle of confusion on the ...

  6. Abbe–Koenig prism - Wikipedia

    en.wikipedia.org/wiki/Abbe–Koenig_prism

    An Abbe–Koenig prism is a type of reflecting prism, used to invert an image (rotate it by 180°). They are commonly used in binoculars and some telescopes for this purpose. The prism is named after Ernst Abbe and Albert Koenig . The prism is made from two glass prisms, which are optically cemented together to form a symmetric, shallow Vee ...

  7. Triangular prism - Wikipedia

    en.wikipedia.org/wiki/Triangular_prism

    Triangular bipyramid. In geometry, a triangular prism or trigonal prism [1] is a prism with 2 triangular bases. If the edges pair with each triangle's vertex and if they are perpendicular to the base, it is a right triangular prism. A right triangular prism may be both semiregular and uniform . The triangular prism can be used in constructing ...

  1. Ad

    related to: bifocal glasses with prisms