When measuring in the IR range, eliminating the effects of water vapor in the instrument is extremely important for obtaining high precision data. Although purging with dry air or nitrogen gas is the conventional solution to this problem, the FT/IR-6X and FT/IR-8X have options for a full or partially evacuable optical system. This system can be used for performing low ppb-level water vapor monitoring, thin-film measurement and dilute solution measurement. Where measurement across wide spectral regions is required, automatic window and/or beam-splitter exchange can be included for uninterrupted spectral acquisition.
Water vapor elimination by vacuum option
Since the vacuum option enables the influence of the atmosphere to be removed effectively compared with the purge option, it enables weak peaks to be detected and the performance of Far IR measurement with high accuracy. The figure below shows the spectra of ultra-low concentration water vapor. Vacuum option is a powerful tool to monitor low concentration gas (less than ppm) and to measure thin film.
Spectra of ultra-low concentration water vapor
The FT/lR-6X and FT/lR-8X spectrometers can be configured for any spectral region within the measurement range 25,000 cm-1 to less than 20 cm-1. Automatic beam splitter and window exchange allow uninterrupted measurement across the entire spectral range.
Automatic beam splitter changer
JASCO can also provide the FTIR system which enables to perform the broad band measurement (6,000 to 30 cm-1) without switching optical elements. In addition, its system can be applied to a vacuum system, which can immediately get the entire spectral data from Mid IR to Far IR without any influence from water vapor or CO2 in the atmosphere.
FT/IR-6X FV FTIR spectrometer (full vacuum model)
The figure below shows the spectra of CaCO3. Since the FTIR system with a broad band beam splitter and broad band detector can immediately get the entire spectral data from Mid IR to Far IR, its system can distinguish the crystal structure difference of CaCO3.
Spectra of CaCO3
Rapid scan and step scan options
For time-resolved measurements, rapid scan option is available for FT/lR-6X and FT/lR-8X. Rapid scan provides measurement up to a maximum of 40 Hz.
Step scan measurement options are also available for FT/lR-8X. Step scan offers microsecond and/or nanosecond measurement options. Step scan measurements require an infinitely repeatable and reproducible experiment. Some key application examples include:
- Depth profiling with PAS
- Thin film measurements with PM-IRRAS
- Chemical transitions in the electric field orientation of liquid crystals
- Materials rheology with polymer stretching
- Protein folding
Dynamic response measurement of liquid crystal (5CB)
(Time resolution: 250 μsec.)
IR microscope options
FTIR microscopy has generally been reserved for measuring specified samples such as small contaminants on polymer films or micro samples transferred to infrared transparent windows. The FT/IR-6X or FT/IR-8X spectrometers can be coupled to any of the IRT Series of IR microscopes to create systems for materials identification and sample imaging.
IRT-7100 IR microscope