Grate separator

Diffraction grating The most common gratings are made of reflecting or transparent sheets marked with fine parallel and equally spaced grooves or rulings. The grating separates polychromatic electromagnetic waves into their components. Similar results can be produced with a prism, but the mechanism is quite different. Fraunhofer used very fine parallel wires in his experiments. 

Lee, B. H. Nishii, J., Dependence of fringe spacing on the grating separation in a long period fiber grating pair, Appl. Opt. 1999, 38, 3450 3459... 

The usual measure of how well a grating separates individual wavelengths is given by the reciprocal linear dispersion, in angstroms per millimeter, as follows ... 

Fig. 8.14. Divergence measurement of H61 with respect to the grating separation obtained at the conditions of self-guided laser propagation...

From the Kinetic Theory of Oases From Grating Separation ... 

This shows that the dispersion is proportional to the grating separation D and increases with X. By choosing the correct value of D one can just compensate the chirp of the pulse generated in the optical fiber and obtain a compressed pulse. 

Diffraction grating (Joseph von Fraunhofer) Von Fraunhofer s diffraction grating separates incident light by color into a rainbow pattern. The various discrete patterns reveal the structure of specific atomic nuclei, making it possible to identify the chemical compositions of various substances. 

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