How do diffraction and dispersion are related? The angle of deviation can also be given by taking the difference between the angle of the incident wave and the angle of the emerging wave. The angle of deviation on the wavelength of the emerging wave. The angle between the incident wave and the deviated wave is called the angle of deviation. The incident wave deviated its direction when it propagated between two mediums or slits. The bent wave that emerges out of the medium is called refracted or diffracted wave. When a wave passes from one medium to another, the wave may bend, making a certain angle θ.
Frequently asked questions What is meant by angle of deviation? For example, when the rainbow is formed, we see the seven colors, which are separated accordingly by their wavelength the white light is first refracted, then dispersed into the colors of the rainbow.įrom the study of diffraction vs dispersion, we know that dispersion is related to both diffraction and refraction, depending on the medium of propagation and the nature of the incident light. When the white light is refracted by a glass prism, we obtain the dispersion of colors of various wavelengths.
The diffraction of sound is already discussed in the previous article.
The formation of a rainbow is also an example of dispersion. When white light travels through the prism, the white light disperses into seven colors of a different wavelength. Holograms and CD which reflects the rainbow colors are due to diffraction The dispersion of the light takes place when the light travels from a denser medium to a rarer medium or vice versa of different refractive indices.Ī diffraction grating is the best example of the diffraction of white light. T he Refractive index of the propagating medium is the leading cause of the dispersion. Refractive indices of the medium Since diffraction depends on the wavelength and frequency of the incident light, which depends on the refractive index of the medium, thus diffraction also depends on the refractive indices of the medium of propagation. If we are using white light for the diffraction process, it depends on the angle of deviation.ĭispersion entirely depends on the angle of minimum deviation. We do not see the dispersion of waves in monochromatic light.ĭiffraction is independent of the angle of deviation of the light if the monochromatic light is used for the diffraction process. We get diffraction fringes of seven colors in the polychromatic, i.e., using white light and fringes of dark and bright by using the monochromatic light.ĭispersion can be achieved only by using white light or polychromatic light. The diffraction can be obtained using both monochromatic and polychromatic light. There will be a change in the velocity of the incident light as the light is travelling between the two mediums of different refractive indices. The velocity of the light before and after diffraction of light remains constant, i.e., diffraction does not affect the velocity. The light with a shorter wavelength disperse first, and then, in increasing order, they spread out of the medium. The spreading up of light waves depends on their wavelength.
The propagation of light waves from one medium to another medium of different refractive indices splits into different wavelengths.ĭiffraction depends on the wavelength of the incident light, as if the light wave of longer wavelength is incident on the slit, it diffracts more. When the light strikes the edge of the hurdle, it bends at the corner, creating the geometrical fringes. The table given below helps you to understand the differences and also similarities between diffraction vs dispersion. In this post, we give a brief comparison of diffraction vs dispersion of light and their behavior. Both terms sound similar, but there are certain natures that differ them from one another. The light wave has the ability to bend and then spread out itself this behavior of light can be distinguished as diffraction and dispersion. In optics, the study of diffraction and dispersion helps us understand the behavior of light, such as the bending and spreading of light when it passes through a medium.