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Grating

Parallel set of linear, regularly repeating grooves that, when illuminated, produces dispersion of light into its requisite wavelengths with maxima and minima of light intensity as a consequence of interference. DiscussionThese maxima and minima vary in position with wavelength. This allows radiation of any given wavelength to be isolated from a mixture of wavelengths (for example, white light) and allows the grating to be used as part of a monochromator. The dispersion or ability to resolve separate wavelengths is expressed as the number of lines (or steps) in the grating per millimetre.

Committee
Trace Materials
Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASTM E2808-21a Standard Guide for Microspectrophotometry in Forensic Paint Analysis. ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428, 2021. Source link
Reprinted, with permission, from ASTM, copyright ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428. A copy of the complete standard may be purchased from ASTM International, https://www.astm.org