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Reflaxicon
An axicon is a specialized type of lens that has a conical surface. An axicon transforms a laser beam into a ring shaped distribution. They can be convex or concave and be made of any optical material. The combination with other axicons or lenses allows a wide variety of beam patterns to be generated. It can be used to turn a Gaussian beam into a non-diffractive Bessel-like beam. Axicons were first proposed in 1954 by John McLeod. Axicons are used in atomic traps and for generating plasma in wakefield accelerators. They are used in eye surgery in cases where a ring-shaped spot is useful. The Axicon is usually characterized by the ratio of the diameter of the ring to the distance from the lens tip to image plane d/l. Special features and Bessel beam shaping Single axicons are usually used to generate an annular light distribution which is laterally constant along the optical axis over a certain range. This special feature results from the generation of (non-diffracting) Bess ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Bessel Beam
Bessel may refer to: Mathematics and science * Bessel beam * Bessel ellipsoid * Bessel function in mathematics * Bessel's inequality in mathematics * Bessel's correction In statistics, Bessel's correction is the use of ''n'' − 1 instead of ''n'' in the formula for the sample variance and sample standard deviation, where ''n'' is the number of observations in a sample. This method corrects the bias in ... in statistics * Bessel filter, a linear filter often used in audio crossover systems * Bessel transform, also known as Fourier-Bessel transform or Hankel transform * Bessel window, in signal processing * Besselian date, see Epoch (astronomy)#Besselian years Places * Bessel Fjord, NE Greenland * Bessel Fjord, NW Greenland * Bessel (crater), a small lunar crater People Surname * Friedrich Wilhelm Bessel (1784–1846), German mathematician, astronomer, and systematizer of the Bessel functions * Johann Franz Bessel (1672–1749), German Benedictine abbot an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
