An optical device, consisting of one or more slits, that selects a narrow band of wavelengths from a broader spectrum.(noun)
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Use "monochromator" in a sentence
"I remember my excitement when I produced helium hydride for the first time and rotated the grating of the monochromator used to record its spectrum, and there was light almost everywhere in the visible and near infrared spectral regions."
"A desired wavelength is selected by diffraction in a suitable crystal or grating, called a monochromator."
"Light was delivered from a 300 W tungsten-halogen lamp via a monochromator (M300, Bentham, UK)."