how does the prismatic signs working?

Question by jiangshan: how does the prismatic signs working?
how does the prismatic signs working?

Best answer:

Answer by Owl
A prism is a transparent optical element with flat, polished surfaces that refract light.
The exact angles between the surfaces depend on the application.
The traditional geometrical shape is that of a triangular prism with a triangular base and rectangular sides, and in colloquial use “prism” usually refers to this type.
Some types of optical prism are not in fact in the shape of geometric prisms.
Prisms are typically made out of glass, but can be made from any material that is transparent to the wavelengths for which they are designed.

A prism can be used to break light up into its constituent spectral colors (the colors of the rainbow).
They can also be used to reflect light, or to split light into components with different polarizations.

As light moves from one medium to another (for example, from air into the glass of the prism), it changes speed.
As a result, the light’s path is bent (refracted) and some of the light is reflected.
The angle that the beam of light makes with the interface, as well as the refractive indices of the two media, determines how much of the light is reflected, and by how much its path is bent. The refractive indices of most media vary with wavelength or color of light, a phenomenon known as dispersion, causing light of different colors to separate when refracted at the surfaces of the prism.

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