enow.com Web Search

Search results

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

    en.wikipedia.org/wiki/Dispersive_prism

    A ray trace through a prism with apex angle α. Regions 0, 1, and 2 have indices of refraction, , and , and primed angles ′ indicate the ray's angle after refraction.. Ray angle deviation and dispersion through a prism can be determined by tracing a sample ray through the element and using Snell's law at each interface.

  3. Fresnel lens - Wikipedia

    en.wikipedia.org/wiki/Fresnel_lens

    In some lenses, the curved surfaces are replaced with flat surfaces, with a different angle in each section. Such a lens can be regarded as an array of prisms arranged in a circular fashion with steeper prisms on the edges and a flat or slightly convex center. In the first (and largest) Fresnel lenses, each section was actually a separate prism.

  4. Prism (geometry) - Wikipedia

    en.wikipedia.org/wiki/Prism_(geometry)

    An oblique prism is a prism in which the joining edges and faces are not perpendicular to the base faces. Example: a parallelepiped is an oblique prism whose base is a parallelogram, or equivalently a polyhedron with six parallelogram faces. Right Prism. A right prism is a prism in which the joining edges and faces are perpendicular to the base ...

  5. Madhava's correction term - Wikipedia

    en.wikipedia.org/wiki/Madhava's_correction_term

    Madhava's correction term is a mathematical expression attributed to Madhava of Sangamagrama (c. 1340 – c. 1425), the founder of the Kerala school of astronomy and mathematics, that can be used to give a better approximation to the value of the mathematical constant π (pi) than the partial sum approximation obtained by truncating the Madhava–Leibniz infinite series for π.

  6. Šidák correction - Wikipedia

    en.wikipedia.org/wiki/Šidák_correction

    The Šidák correction is derived by assuming that the individual tests are independent. Let the significance threshold for each test be α 1 {\displaystyle \alpha _{1}} ; then the probability that at least one of the tests is significant under this threshold is (1 - the probability that none of them are significant).

  7. PRISM - Wikipedia

    en.wikipedia.org/wiki/PRISM

    Class action lawsuit against government bodies and officials believed responsible for PRISM, and 12 companies (including Apple, Microsoft, Google, Facebook, and Skype and their chief executives) who have been disclosed as providing or making available mass information about their users' communications and data to the NSA under the PRISM program ...

  8. Binoculars - Wikipedia

    en.wikipedia.org/wiki/Binoculars

    Porro prism designs have the added benefit of folding the optical path so that the physical length of the binoculars is less than the focal length of the objective. Porro prism binoculars were made in such a way to erect an image in a relatively small space, thus binoculars using prisms started in this way.

  9. List of formulae involving π - Wikipedia

    en.wikipedia.org/wiki/List_of_formulae_involving_π

    More formulas of this nature can be given, as explained by Ramanujan's theory of elliptic functions to alternative bases. Perhaps the most notable hypergeometric inversions are the following two examples, involving the Ramanujan tau function τ {\displaystyle \tau } and the Fourier coefficients j {\displaystyle \mathrm {j} } of the J-invariant ...