05-12-2017, 11:40 AM
In optics 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 geometric shape is that of a triangular prism with a triangular base and rectangular sides, and in colloquial use "prism" generally refers to this type. Some types of optical prisms are not in fact in the form of geometric prisms. The prisms can be made of any material that is transparent to the wavelengths for which they are designed. Typical materials include glass, plastic and fluorite. A prism can be used to divide the light into its constituent spectral colors (the colors of therainbow). Prisms can also be used to reflect light or to divide light into components with different polarizations.
The optical properties of a medium often manage the interaction of the electromagnetic wave incident on it. Therefore, an electromagnetic wave begins to interact with the electrons in a medium, when the wave is allowed to propagate through it. The electric field associated with the wave makes them vibrate and these forced oscillations of the electrons in the middle begin to radiate light offering secondary sources of radiation. However, the speed of the new waves changes according to the optical properties of the medium and is always smaller than the speed of light in a vacuum. All materials are characterized by their ability to slow the waves, classified as optical refractive index. The refractive index of the vacuum is unitary and is greater than unity for any other material (for example, n = 1.33 for water).
