For measurements in which a spectrum may be affected by atmosphere components, such as water vapor or carbon dioxide, purging of the interferometer and sample chamber with dry nitrogen offers significant improvements in data quality. The optional vacuum IRT-5000/7000 is a much more effective way to eliminate the influence of atmospheric gases.

*A vacuum IRT microscope (IRT-5200VC/7200VC) should be configured with a vacuum FTIR spectrometer (FT/IR-6X VC/8X VC). The IRT-5200VC can only be configured with the FT/IR/6X VC while the IRT-7200VC can be configured with either the FT/IR-6X VC or the FT/IR-8X VC. In addition, an automatic vacuum panel (AVC-6X) is required.