What is a series of fine slits or lines used to deviate waves, such as light, called?

A series of fine slits or lines designed to deviate waves, such as light, is referred to as a diffraction grating. This tool works on the principle of diffraction, which occurs when waves encounter an obstacle or opening that is comparable in size to their wavelength. Each slit in the grating allows light to pass through, resulting in the light waves spreading out and creating interference patterns.

The spacing of the slits determines the angles at which the light waves interfere constructively or destructively, leading to bright and dark fringes. This is a crucial concept in wave optics, as diffraction gratings are widely used to analyze the spectral composition of light sources, making them essential in applications ranging from spectroscopy to telecommunications.

In contrast, a waveguide is primarily used to direct waves along a specific path rather than producing diffraction patterns. An optical lens focuses light using refraction instead of exploiting slits or lines, while a prism disperses light into its component colors based on different degrees of refraction. Each of these components plays distinct roles in wave manipulation, but only a diffraction grating directly utilizes closely spaced slits to deviate waves systematically.