Uv visible instrument types

Single beam UV-visible spectrophotometers have a light source, filter/monochromator, sample cell, and detector but lack a reference cell for comparison. Double beam UV-visible spectrophotometers contain a light source, filter/monochromator, sample cell, reference cell, beam splitter, and two detectors, allowing rapid scanning by reducing fluctuations between measurements. While single beam instruments are simpler, double beam spectrophotometers provide more accurate readings through direct comparison of sample and reference signals.