Flow-through, inlet-gas-temperature-controlled, solvent-resistant, thermal-expansion compensated cell for light spectroscopy

Optical cells include a spacer formed of a hydrocarbon-resistant polymer, so that fluids such as hydrocarbons and alcohols can be introduced to a sample space, or include a fluid inlet and a heated inlet tube, so that a humid gas can be introduced to the sample space without condensation occurring. Optical cells can be used with, for example, solid, gel, and liquid samples. Measurements can be performed with various selected sample gaps of an optical cell.