Question

Why is a diffraction grating better than a prism?

Answer 1

In optics, a diffraction grating is a periodic optical component that divides and diffracts light into several beams travelling in various directions. The colouring that is developing is a type of structural coloration. The grating serves as a dispersive element since the directions of these beams are determined by the spacing of the grating and the wavelength of the light. Gratings are widely employed in monochromators and spectrometers as a result of this.

Complete answer:
For analysis, prisms may disperse light spectra into a variety of hues. This is frequently sufficient. A diffraction grating performs a similar function. A diffraction grating, on the other hand, is less sensitive to light colour and may be designed to disperse colours across a greater angle than a prism.
A prism's glass is transparent to visible light, but it absorbs and blocks light in the infrared and ultraviolet ranges. Chemical analysis frequently relies on recognising certain hues from the sample's spectrum that are outside of the visual range.
The wavelength ( $\lambda$ ) and the distance between lines (d) can be used to define the angle of the first-order deflection ( $\theta$ ).
$tan\left( \theta \right)=\lambda d$
Light in the centre of the visible spectrum may be deflected by at least 20 degrees using a diffraction grating with a few hundred lines per inch. A glass prism's deflection angle is usually much lower than this.
The spectrograph then re-images the scattered light and directs the appropriate wavelength range to a detecting device. Gratings are made up of parallel grooves that are evenly spaced on a reflective coating and placed on a substrate. The blaze angle (the form of the grooves) determines which wavelength range the grating is best suited for. The blaze angle (the form of the grooves) determines which wavelength range the grating is best suited for. The distance between neighbouring grooves and the groove angle determine the grating's dispersion and efficiency.
Gratings are typically superior to prisms because they are more efficient, give a linear dispersion of wavelengths, and are free of the absorption effects that restrict the wavelength range of prisms.

Note:
An optical prism is a light-refracting transparent optical device having flat, polished surfaces. Prisms must have at least one angled surface; components with two parallel surfaces are not prisms. A triangular prism with a triangle base and rectangular sides is the typical geometrical shape of an optical prism, and "prism" is commonly used to refer to this kind. Some optical prisms do not have the same form as geometric prisms. Prisms can be manufactured out of any material that is transparent to the wavelengths they are intended for.