echelette grating

echelette grating

[¦esh·ə¦let or ¦āsh¦let ‚grād·iŋ]
(spectroscopy)
A diffraction grating with coarse groove spacing, designed for the infrared region; has grooves with comparatively flat sides and concentrates most of the radiation by reflection into a small angular coverage.
References in periodicals archive ?
Compact, PI-Echelle consists of a prism and echelette grating to capture high resolution spectra over a range of 190 to 1100 nm in a single acquisition Medical scanning is not required.