Although color measurement is widely used in quality control, it is not routinely automated. Most color measurement centers on reflectance rather than transmission measurement. To automate color measurement of liquids meant that we had to design a flow-through cell which would give equivalent results to a manual cell. The flowcell shows comparable results to the manual cell regardless of the angle of the observer.
Jack A. Ladson,
"Automated in-line color measurement for quality control", Proc. SPIE 1681, Optically Based Methods for Process Analysis, (14 August 1992); doi: 10.1117/12.137736; https://doi.org/10.1117/12.137736