Dispersive prism
[1] This is a result of the prism material's index of refraction varying with wavelength (dispersion).
Other types of dispersive prism exist that have more than two optical interfaces; some of them combine refraction with total internal reflection.
Light changes speed as it moves from one medium to another (for example, from air into the glass of the prism).
This speed change causes the light to be refracted and to enter the new medium at a different angle (Huygens principle).
The refractive index of many materials (such as glass) varies with the wavelength or color of the light used, a phenomenon known as dispersion.
Prisms will generally disperse light over a much larger frequency bandwidth than diffraction gratings, making them useful for broad-spectrum spectroscopy.
to be approximated by The deviation angle depends on wavelength through n, so for a thin prism the deviation angle varies with wavelength according to Aligning multiple prisms in series can enhance the dispersion greatly, or vice versa, allow beam manipulation with suppressed dispersion.
Therefore, the resulting dispersion is not a simple sum of individual contributions (unless all prisms can be approximated as thin ones).
Fused quartz, sodium chloride and other optical materials are used at ultraviolet and infrared wavelengths where normal glasses become opaque.
Like many basic geometric terms, the word prism (Greek: πρίσμα, romanized: prisma, lit.
Euclid defined the term in Book XI as "a solid figure contained by two opposite, equal and parallel planes, while the rest are parallelograms", however the nine subsequent propositions that used the term included examples of triangular-based prisms (i.e. with sides which were not parallelograms).
Isaac Newton's 1666 experiment of bending white light through a prism demonstrated that all the colors already existed in the light, with different color "corpuscles" fanning out and traveling with different speeds through the prism.
The results of the experiment dramatically transformed the field of metaphysics, leading to John Locke's primary vs secondary quality distinction.
[citation needed] Newton discussed prism dispersion in great detail in his book Opticks.
A quantitative description of multiple-prism dispersion was not needed until multiple prism laser beam expanders were introduced in the 1980s.
[8] A diffraction grating may be ruled onto one face of a prism to form an element called a "grism".
Any effect due to chromatic dispersion from the prism itself is incidental, as opposed to actual prism-based spectrometers.
An artist's rendition of a dispersive prism is seen on the cover of Pink Floyd's The Dark Side of the Moon, one of the best-selling albums of all time.
