Bandwidth, Resolution, Reporting Interval, And The UltraScan PRO

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Of the many specifications frequently given for spectrophotometers, three relate to the ability of the instrument to accurately measure samples having steep slopes (quick changes) in their spectral reflectance or transmittance curves. They are effective bandwidth, wavelength resolution, and reporting interval.

Effective Bandwidth
Effective bandwidth indicates the ability of an instrument's polychromator optics to see small wavelength differences in spectral curves or to resolve spectral peaks that are close together. (The polychromator is the part of the instrument that divides the white source light reflected back from or transmitted through the sample into its various component wavelengths for detection. The UltraScan PRO uses two holographic grating polychromators.) For example, if a sample had two spectral peaks that were 8 nanometers (nm) apart, an instrument with a 10-nm effective bandwidth would see only one peak. An instrument with a 5-nm effective bandwidth would correctly see the two peaks.