Haidinger fringes are
interference fringe
In physics, interference is a phenomenon in which two coherent waves are combined by adding their intensities or displacements with due consideration for their phase difference. The resultant wave may have greater amplitude (constructive in ...
s formed by the
interference
Interference is the act of interfering, invading, or poaching. Interference may also refer to:
Communications
* Interference (communication), anything which alters, modifies, or disrupts a message
* Adjacent-channel interference, caused by extra ...
of
monochromatic
A monochrome or monochromatic image, object or palette is composed of one color (or values of one color). Images using only shades of grey are called grayscale (typically digital) or black-and-white (typically analog). In physics, mon ...
and
coherent light
Coherence expresses the potential for two waves to Wave interference, interfere. Two Monochromatic radiation, monochromatic beams from a single source always interfere. Wave sources are not strictly monochromatic: they may be ''partly coherent''. ...
to form visible dark and bright fringes. Fringe localization is the region of space where fringes with reasonably good
contrast are observed.
Haidinger fringes are fringes localized at
infinity
Infinity is something which is boundless, endless, or larger than any natural number. It is denoted by \infty, called the infinity symbol.
From the time of the Ancient Greek mathematics, ancient Greeks, the Infinity (philosophy), philosophic ...
. Also known as fringes of equal inclination, these fringes result when light from an
extended source falls on a
thin film
A thin film is a layer of materials ranging from fractions of a nanometer ( monolayer) to several micrometers in thickness. The controlled synthesis of materials as thin films (a process referred to as deposition) is a fundamental step in many ...
made of an
optically denser medium. These fringes indicate the positions where light interferes, emerging from the medium at an equal angle.
[ Hecht ] They are also observed in
Fabry-Pérot and
Michelson interferometer
The Michelson interferometer is a common configuration for optical interferometry and was invented by the American physicist Albert Abraham Michelson in 1887. Using a beam splitter, a light source is split into two arms. Each of those light be ...
s. They can be observed by introducing a
converging lens
A lens is a transmissive optical device that focuses or disperses a light beam by means of refraction. A simple lens consists of a single piece of transparent material, while a compound lens consists of several simple lenses (''elements''), ...
between the film and observation plane with
focus
Focus (: foci or focuses) may refer to:
Arts
* Focus or Focus Festival, former name of the Adelaide Fringe arts festival in East Australia Film
*Focus (2001 film), ''Focus'' (2001 film), a 2001 film based on the Arthur Miller novel
*Focus (2015 ...
of the lens lying in observation plane.
See also
*
Wilhelm Karl Ritter von Haidinger
Wilhelm Karl Haidinger (5 February 179519 March 1871), ennobled as Wilhelm Ritter von Haidinger in 1864, was an Austrian mineralogist.
Early life
Haidinger's father was the mineralogist Karl Haidinger (1756–1797), who died when Wilhelm was o ...
*
Haidinger's brush
Haidinger's brush, more commonly known as Haidinger's brushes is an image produced by the eye, an entoptic phenomenon, first described by Austrian physicist Wilhelm Karl von Haidinger in 1844. Haidinger saw it when he looked through various mine ...
References
*
*
;Specific
Interference
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