Diffraktiohilaissa

Diffraktiohilaissa, known in English as a diffraction grating, is an optical component with a regularly repeating structure that splits and diffracts light into several beams traveling in different directions. The behavior of light with a diffraction grating is governed by the principles of diffraction and interference. When light encounters the grating, each slit or groove acts as a source of secondary wavelets, which then interfere with each other.

The spacing between these regularly repeating elements, called the grating period or pitch, is crucial. For visible light, this spacing is typically on the order of the wavelength of light itself, usually a few hundred nanometers to a few micrometers. The angle at which the diffracted light is observed depends on the wavelength of the incident light and the grating period. This phenomenon allows diffraction gratings to be used as dispersing elements, separating light into its constituent wavelengths, similar to a prism but often with higher resolution.

Diffraction gratings can be fabricated in various ways, including ruling fine lines on a surface or by photolithographic techniques. They can be transmissive, where light passes through, or reflective, where light is reflected off the surface. Applications are widespread, including in spectrometers for analyzing the spectral composition of light, in telecommunications for wavelength division multiplexing, and in various scientific instruments where precise control and separation of light wavelengths are required. The phenomenon of diffraction was first observed by Francesco Maria Grimaldi in 1665.