When.com Web Search

Search results

  1. Results From The WOW.Com Content Network
  2. Luminescence - Wikipedia

    en.wikipedia.org/wiki/Luminescence

    Cryoluminescence, the emission of light when an object is cooled [6] (an example of this is wulfenite) Photoluminescence, a result of the absorption of photons Fluorescence, traditionally defined as the emission of light that ends immediately after the source of excitation is removed. As the definition does not fully describe the phenomenon ...

  3. List of light sources - Wikipedia

    en.wikipedia.org/wiki/List_of_light_sources

    This is a list of sources of light, the visible part of the electromagnetic spectrum.Light sources produce photons from another energy source, such as heat, chemical reactions, or conversion of mass or a different frequency of electromagnetic energy, and include light bulbs and stars like the Sun. Reflectors (such as the moon, cat's eyes, and mirrors) do not actually produce the light that ...

  4. Single-photon source - Wikipedia

    en.wikipedia.org/wiki/Single-photon_source

    Individual atoms emit two photons at different frequencies in the cascade transition and by spectrally filtering the light the observation of one photon can be used to 'herald' the other. The observation of these single photons was characterised by its anticorrelation on the two output ports of a beamsplitter in a similar manner to the famous ...

  5. Blacklight - Wikipedia

    en.wikipedia.org/wiki/Blacklight

    A blacklight, also called a UV-A light, Wood's lamp, or ultraviolet light, is a lamp that emits long-wave ultraviolet light and very little visible light. [ 1 ] [ 2 ] [ 3 ] One type of lamp has a violet filter material, either on the bulb or in a separate glass filter in the lamp housing, which blocks most visible light and allows through UV ...

  6. Cathode-ray tube - Wikipedia

    en.wikipedia.org/wiki/Cathode-ray_tube

    A cathode-ray tube (CRT) is a vacuum tube containing one or more electron guns, which emit electron beams that are manipulated to display images on a phosphorescent screen. [2] The images may represent electrical waveforms on an oscilloscope , a frame of video on an analog television set (TV), digital raster graphics on a computer monitor , or ...

  7. Blue laser - Wikipedia

    en.wikipedia.org/wiki/Blue_laser

    They most commonly emit light at 473 nm, which is produced by frequency doubling of 946 nm laser radiation from a diode-pumped Nd:YAG or Nd:YVO4 crystal. [24] Neodymium-doped crystals usually produce a principal wavelength of 1064 nm, but with the proper reflective coating mirrors can be also made to lase at other non-principal neodymium ...

  8. Ionized-air glow - Wikipedia

    en.wikipedia.org/wiki/Ionized-air_glow

    Nitrogen glow Oxygen glow Electrical discharge in air Particle beam from a cyclotron. Ionized-air glow is the luminescent emission of characteristic blue–purple–violet light, often of a color called electric blue, by air subjected to an energy flux either directly or indirectly from solar radiation.

  9. Light-emitting diode - Wikipedia

    en.wikipedia.org/wiki/Light-emitting_diode

    Light pollution: Because white LEDs emit more short wavelength light than sources such as high-pressure sodium vapor lamps, the increased blue and green sensitivity of scotopic vision means that white LEDs used in outdoor lighting cause substantially more sky glow.