The spiral grooves on a compact disk make them act as these devices, explaining their iridescence. For 10 points each:
[10m] Name these devices that, like prisms, are commonly used to separate light in a monochromator.
ANSWER: diffraction gratings
[10e] A grating prism combination called a grism keeps only light of a specific value of this quantity undeviated. This quantity symbolized lambda equals wave speed over frequency.
ANSWER: wavelength
[10h] This type of diffraction grating is grooved at a namesake angle to maximize diffraction in a specific order. A specific type of these gratings are used in the HARPS (“harps”) spectrograph for exoplanet hunting.
ANSWER: blazed gratings [or echellette (“eh-shell-ET”) gratings; accept blaze angle; accept echelle (“eh-SHELL”) gratings]
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