A system using interaction of evanescent light waves with particles in a liquid allows one to observe accumulation, stability, and adhesion of such particles at and in the vicinity of a surface. Accumulation can be due to electrophoresis, sedimentation, or equilibration of the substrate surface with the bulk solution. The observation is sensitive only to particles within 1 μm of the interface, so it can be made with an arbitrary thickness of fluid. Evanescent wave absorption is monitored adjacent to an indium tin oxide coated glass slide affixed to a high index prism. The test fluid can be either constrained by a secondary metal electrode or left as a free fluid film. In the latter case a free charge can be injected into the system from an external charge generator allowing one to separate field- and charge-induced effects. This system is ideal for investigating device life limiting interactions between colorants and substrates in displays.