enow.com Web Search

  1. Ads

    related to: adding prism to eyeglass lenses pros and cons

Search results

  1. Results from the WOW.Com Content Network
  2. Porro prism - Wikipedia

    en.wikipedia.org/wiki/Porro_prism

    Porro prisms are most often used in pairs, forming a double Porro prism. A second prism rotated 90° with respect to the first, is placed such that light will traverse both prisms. The net effect of the prism system is a beam parallel to but displaced from its original direction, with the image rotated 180°. A double Porro system provides four ...

  3. Catadioptric system - Wikipedia

    en.wikipedia.org/wiki/Catadioptric_system

    A catadioptric optical system is one where refraction and reflection are combined in an optical system, usually via lenses ( dioptrics) and curved mirrors ( catoptrics ). Catadioptric combinations are used in focusing systems such as searchlights, headlamps, early lighthouse focusing systems, optical telescopes, microscopes, and telephoto lenses.

  4. Lenticular lens - Wikipedia

    en.wikipedia.org/wiki/Lenticular_lens

    Lenticular eyeglass lenses have been employed to correct extreme hyperopia (farsightedness), a condition often created by cataract surgery when lens implants are not possible. To limit the great thickness and weight that such high-power lenses would otherwise require, all the power of the lens is concentrated in a small area in the center.

  5. Varifocal lens - Wikipedia

    en.wikipedia.org/wiki/Varifocal_lens

    Varifocal lens. A varifocal lens is a camera lens with variable focal length in which focus changes as focal length (and magnification) changes, as compared to a parfocal ("true") zoom lens, which remains in focus as the lens zooms (focal length and magnification change). Many so-called "zoom" lenses, particularly in the case of fixed-lens ...

  6. Phoropter - Wikipedia

    en.wikipedia.org/wiki/Phoropter

    This was a device produced in Camden, New Jersey, which contained a battery of convex lenses for each eye, a battery of concave lenses for each eye, and auxiliary lenses which gave it a total power range of +15.75 to -19.75, as well as a Maddox rod and Risley prism for each eye, and a Steven's phorometer.

  7. PRISM (reactor) - Wikipedia

    en.wikipedia.org/wiki/PRISM_(reactor)

    The S-PRISM represents GEH's Generation IV reactor solution to closing the nuclear fuel cycle and is also part of its Advanced Recycling Center (ARC) proposition [1] to U.S. Congress to deal with nuclear waste. [2] S-PRISM is a commercial implementation of the Integral Fast Reactor developed by Argonne National Laboratory between 1984 and 1994.