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color
(Encyclopedia)color, effect produced on the eye and its associated nerves by light waves of different wavelength or frequency. Light transmitted from an object to the eye stimulates the different color cones of the...laser
(Encyclopedia) CE5 Ordinary light sources produce incoherent light, while a laser produces a beam of coherent light. laser [acronym for light amplification by stimulated emission of radiation], device for the cr...night blindness
(Encyclopedia)night blindness, inability to see normally in subdued light. It is usually a result of vitamin A deficiency. The rod cells, one of two light-sensitive areas of the retina of the eye, are impaired in t...albedo
(Encyclopedia)albedo ălbēˈdō [key], reflectivity of the surface of a planet, moon, asteroid, or other celestial body that does not shine by its own light. Albedo is measured as the fraction of incident light th...photoelectric effect
(Encyclopedia)photoelectric effect, emission of electrons by substances, especially metals, when light falls on their surfaces. The effect was discovered by H. R. Hertz in 1887. The failure of the classical theory ...image
(Encyclopedia)image, in optics, likeness or counterpart of an object produced when rays of light coming from that object are reflected from a mirror or are refracted by a lens. An image of an object is also formed ...tachyon
(Encyclopedia)tachyon tăkˈēŏnˌ [key], hypothetical elementary particle that travels only at speeds exceeding that of light. According to the theory of relativity, the speed of light is the limiting velocity fo...Hovhaness, Alan
(Encyclopedia)Hovhaness, Alan hōvhäˈnəs [key], 1911–2000, American composer, b. Somerville, Mass., as Alan Vaness Chakmakjian. Hovhaness was of Armenian and Scottish descent, and many of his works are based o...refraction
(Encyclopedia)refraction, in physics, deflection of a wave on passing obliquely from one transparent medium into a second medium in which its speed is different, as the passage of a light ray from air into glass. O...Nakamura, Shuji
(Encyclopedia)Nakamura, Shuji, 1954–, Japanese physicist and electronics engineer, grad. Univ. of Tokushima (D.Eng., 1994). Nakamura joined the Nichia Corporation in 1977, and it was there that he began his life-...Browse by Subject
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