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physical object > artifact > device > instrument > optical device > wavefront modifier > spectrograph dispersing element

spectrograph dispersing element
subject			fact

spectrograph dispersing element	has dispersion
	has wavefront modification wavelength
	has definition The part of a spectrograph which disperses the light into component colors
	is a kind of wavefront modifier
instrument	has operator
artifact	has creator
	has creation date
	has purpose
	has owner
physical object	has location or center of gravity
	has angular momentum
	has mass
	has velocity
	has momentum
	has temperature
	has volume
	has extent
	has material

Kinds of spectrograph dispersing element :

• diffraction grating (4 kinds, 12 facts) - Polished metallic surface (usually a metallic mirror on a block of glass or quartz) on which has been ruled a great number (in thousands) of parallel lines, used to split light to produce a spectrum., A system of parallel slits, where the slit width is of the same order as the wavelength of the incident radiation, which is capable of dispersing light into its spectrum., An optical device containing thousands of very fine parallel grooves which produce interference patterns in a way which separates out all the components of the light into a spectrum.
• Fabry-Perot interferometer (1 kind, 6 facts) (FP) - A type of interferometer wherein the beam of light is passed through a series of pairs of partly reflecting surfaces set at various angles to it and spaced at certain prechosen numbers of the wavelength to be examined. It differs from the Michelson interferometer in that it has only one arm., A device that measures distances and changes of distance very accurately, using the pattern of overlap of waves of light.
• interference filter (3 facts) - A filter used to shut out all light except the desired wavelengths., A method of constructing an optical filter to select a particular wavelength band for transmission and reject wavelengths outside this band. Similar to a Fabry-Perot etalon. The construction relies on constructive and destructive interference effects in a multilayer stack of quarter-wave reflective layers and half-wave spacer layers.
• objective prism (2 facts) - A small-angle prism placed in front of a telescope objective to transform each star image in a field of stars into an image of its spectrum.

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