échelle spectrographA spectrograph that uses an échelle grating to achieve high spectral resolution and wide wavelength coverage. The overlapping spectra produced by the grating are separated by a prism or a grism before reaching the detector. The sensitivity brought to modern échelle spectrographs by CCD detectors has made them indispensable in such fields as astroseismology and extrasolar planet searches. Related category• SPECTRA AND SPECTROSCOPYAlso on this site: Encyclopedia of Alternative Energy & Sustainable Living Encyclopedia of History |