enow.com Web Search

Search results

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

    en.wikipedia.org/wiki/Fresnel_lens

    The Fresnel lens reduces the amount of material required compared to a conventional lens by dividing the lens into a set of concentric annular sections. An ideal Fresnel lens would have an infinite number of sections. In each section, the overall thickness is decreased compared to an equivalent simple lens.

  3. Magnifying glass - Wikipedia

    en.wikipedia.org/wiki/Magnifying_glass

    A magnifying glass is a convex lens that is used to produce a magnified image of an object. The lens is usually mounted in a frame with a handle. Beyond its primary function of magnification, this simple yet ingenious tool serves a variety of purposes. It can be employed to focus sunlight, harnessing the Sun's rays to create a concentrated hot ...

  4. Biology in fiction - Wikipedia

    en.wikipedia.org/wiki/Biology_in_fiction

    Boris Karloff in James Whale's 1931 film Frankenstein, based on Mary Shelley's 1818 novel.The monster is created by an unorthodox biology experiment.. Biology appears in fiction, especially but not only in science fiction, both in the shape of real aspects of the science, used as themes or plot devices, and in the form of fictional elements, whether fictional extensions or applications of ...

  5. History of lighthouses - Wikipedia

    en.wikipedia.org/wiki/History_of_lighthouses

    A Fresnel lens can also capture more oblique light from a light source, thus allowing the light from a lighthouse equipped with one to be visible over greater distances. The first Fresnel lens was used in 1823 in the Cordouan Lighthouse at the mouth of the Gironde estuary in France; its light could be seen from more than 20 miles (32 km) out ...

  6. Fresnel equations - Wikipedia

    en.wikipedia.org/wiki/Fresnel_equations

    The Fresnel equations give the ratio of the reflected wave's electric field to the incident wave's electric field, and the ratio of the transmitted wave's electric field to the incident wave's electric field, for each of two components of polarization. (The magnetic fields can also be related using similar coefficients.)

  7. 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.

  8. Augustin-Jean Fresnel - Wikipedia

    en.wikipedia.org/wiki/Augustin-Jean_Fresnel

    Augustin-Jean Fresnel. Augustin-Jean Fresnel[ Note 1] (10 May 1788 – 14 July 1827) was a French civil engineer and physicist whose research in optics led to the almost unanimous acceptance of the wave theory of light, excluding any remnant of Newton 's corpuscular theory, from the late 1830s [ 3] until the end of the 19th century. He is ...

  9. Space sunshade - Wikipedia

    en.wikipedia.org/wiki/Space_sunshade

    In 2004, physicist and science fiction author Gregory Benford calculated that a concave rotating Fresnel lens 1000 kilometres across, yet only a few millimeters thick, floating in space at the L 1 point, would reduce the solar energy reaching the Earth by approximately 0.5% to 1%. [18] The cost of such a lens has been disputed.