Diffuse reflectance spectroscopic analysis of barium sulfate as a reflection standard within 173–2500 nm: From pure to sintered form

Abstract

The use of barium sulfate (BaSO₄) as a low-cost reflectance standard has been documented for some time. In its pure salt form, the optical characteristics do have advantages compared to laboratory-grade sintered polytetrafluoroethylene (PTFE). However, its practical use has little advantage against the stability of PTFE. In this paper, a process of producing pelletized BaSO₄, and characterization of its optical reflectance properties is reported. In its sintered form, data-driven analysis shows that BaSO₄ is a commendable low-cost, high-reflection and a high-consistency material. The current sintered forms, though crude, registers a relatively stable texture to withstand minor mechanical stress, while having up to an average 92% reflectivity across the UV-VIS-NIR range (173–2500 nm) compared to a PTFE reflection standard.