An error which arises from the fact that the
absorbance of a sample (especially a solid) could depend on the
polarization of the incident radiation and from the
polarization dependent response of the photodetector.
Source:
PAC, 1988, 60, 1449
(Nomenclature, symbols, units and their usage in spectrochemical analysis - VII. Molecular
absorption spectroscopy, ultraviolet and visible (UV/VIS) (Recommendations 1988))
on page 1456