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The word laser is an anacronym that originated as an acronym for light amplification by stimulated emission of radiation. [1] [2] The first laser was built in 1960 by Theodore Maiman at Hughes Research Laboratories, based on theoretical work by Charles H. Townes and Arthur Leonard Schawlow.
A laser weapon is a type of directed-energy weapon that uses lasers to inflict damage. Whether they will be deployed as practical, high-performance military weapons remains to be seen. One of the major issues with laser weapons is atmospheric thermal blooming, which is still largely unsolved. This issue is exacerbated when there is fog, smoke ...
Prism (optics) An optical prism is a transparent optical element with flat, polished surfaces that are designed to refract light. At least one surface must be angled — elements with two parallel surfaces are not prisms. The most familiar type of optical prism is the triangular prism, which has a triangular base and rectangular sides.
2. How about an illustration to visually explain what it meant by the "prism dioptres" section? 3. Can prismatic lenses be included with bifocals, progressive lenses, polarizing, tinting, Crizol lenses, etc? 4. Hillary Rodham Clinton used prismatic lenses temporarily after her concussion, although her article doesn't mention that. What other ...
Lunar Laser Ranging (LLR) is the practice of measuring the distance between the surfaces of the Earth and the Moon using laser ranging. The distance can be calculated from the round-trip time of laser light pulses travelling at the speed of light , which are reflected back to Earth by the Moon's surface or by one of several retroreflectors ...
In roof prism designs, optically relevant prism angles must be correct within 2 arcseconds (1 / 1,800 of 1 degree) to avoid seeing an obstructive double image. Maintaining such tight production tolerances for the alignment of their optical elements by laser or interference (collimation) at an affordable price point is challenging.
t. e. PRISM is a code name for a program under which the United States National Security Agency (NSA) collects internet communications from various U.S. internet companies. [1] [2] [3] The program is also known by the SIGAD US-984XN. [4] [5] PRISM collects stored internet communications based on demands made to internet companies such as Google ...
Canon NS (1939) New Standard. A Canon S without the slow shutter speeds. Canon J (1939) J stands for Junior a non-rangefinder model. Canon J II (1946) Similar if not the same as prewar cameras. Canon S (1946) Similar if not the same as prewar cameras. Canon S II (1946) A redesign with combined range finder and viewfinder functions – two windows.