Diffraction Grating

In optics, a diffraction grating is an optical component with a periodic structure, which splits and diffracts light into several beams travelling in different directions. The directions of these beams depend on the spacing of the grating and the wavelength of the light so that the grating acts as the dispersive element. Because of this, gratings are commonly used in monochromators and spectrometers.

A photographic slide with a fine pattern of purple lines forms a complex grating. For practical applications, gratings generally have ridges or rulings on their surface rather than dark lines. Such gratings can be either transmissive or reflective. Gratings which modulate the phase rather than the amplitude of the incident light are also produced, frequently using holography.

The principles of diffraction gratings were discovered by James Gregory, about a year after Newton's prism experiments, initially with artifacts such as bird feathers. The first man-made diffraction grating was made around 1785 by Philadelphia inventor David Rittenhouse, who strung hairs between two finely threaded screws. This was similar to notable German physicist Joseph von Fraunhofer's wire diffraction grating in 1821.

Diffraction creates the "Rainbow" colors reflected from a Compact Disc (see Examples, below). A grating has parallel lines, while a CD has a spiral of finely-spaced data tracks. Diffraction colors also appear when one looks at a bright point source through a translucent fine-pitch umbrella-fabric covering. Decorative patterned plastic films based on reflective grating patches are very inexpensive to produce, and very commonplace.

Read more about Diffraction GratingTheory of Operation, Gratings As Dispersive Elements, Fabrication, Examples

Other articles related to "diffraction grating, grating, gratings, diffraction, diffraction gratings":

Diffraction of Light - Diffraction Grating
... A diffraction grating is an optical component with a regular pattern ... The form of the light diffracted by a grating depends on the structure of the elements and the number of elements present, but all gratings have intensity maxima at ... The light diffracted by a grating is found by summing the light diffracted from each of the elements, and is essentially a convolution of diffraction and interference patterns ...
Talbot Effect
... The Talbot effect is a near-field diffraction effect first observed in 1836 by Henry Fox Talbot ... When a plane wave is incident upon a periodic diffraction grating, the image of the grating is repeated at regular distances away from the grating plane ... meaning of this is that it is laterally shifted by half the width of the grating period) ...
Airborne Real-time Cueing Hyperspectral Enhanced Reconnaissance - Technical Description - Hyperspectral Imager
... line image is then projected onto a diffraction grating, which is a very finely etched reflecting surface that disperses light into its spectra ... The diffraction grating is specially constructed and positioned to create a two-dimensional (2D) spectrum image from the horizontal line image ... perpendicular to the line image, by the design and arrangement of the diffraction grating ...
Joseph Von Fraunhofer - Invention and Scientific Research
... Fraunhofer also developed a diffraction grating in 1821, which occurred after James Gregory discovered the principles of diffraction grating and after American astronomer David Rittenhouse invented ...
Diffraction Grating - Examples - Natural Gratings
... muscle is the most commonly found natural diffraction grating and, indeed, this has helped physiologists in determining the structure of such muscle ... from this, the chemical structure of crystals can be thought of as diffraction gratings for other types of electromagnetic radiation other than visible light, this is the basis ... Most commonly confused with diffraction gratings are the iridescent colors of peacock feathers, mother-of-pearl, and butterfly wings ...