https://doi.org/10.1351/goldbook.S05847
A device which enables visual observation and evaluation of optical spectra (usually confined to the @VT07496@ spectral region).
Source:
PAC, 1995, 67, 1725. (Nomenclature, symbols, units and their usage in spectrochemical analysis-IX. Instrumentation for the spectral dispersion and isolation of optical radiation (IUPAC Recommendations 1995)) on page 1729 [Terms] [Paper]