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Recently, the high-brilliance infrared synchrotron radiation source out of various infrared sources has become popular, and it is widely used in many fields of studies. For spectroscopy, the HgCdTe (MCT) detector is often used. It covers a wide mid-infrared region and has high sensitivity, but saturates easily. In this work, the detector saturation behavior was investigated in detail using infrared synchrotron radiation and infrared free electron laser. We found that the saturation and its elimination show various patterns depending on the amplifier gain, light intensity and the time structure of the light. The influence of the saturation to the spectral shape is also discussed.

BL43IR at SPring-8 is overviewed regarding the beamline properties on the flux, the brilliance and the noise in comparison with the conventional thermal radiation (TR). The flux is comparable to the TR, and what makes the most of BL43IR is to utilize the high brilliance. We redirect our strategy to concentrate on the microscopes with highly brilliant infrared radiation from SPring-8 and attract the vast TR spectroscopy community.

Vibration bands of dielectric ceramics appear at a mid-infrared (MIR) and those position and shape are changed owing to change environment of crystal lattice. Therefore, micro-focus MIR spectroscopy is a one of useful tool to evaluate very small size capacitor (e.g. smaller than 0.5 mm in chip size). Very small size multi-layer capacitor: MLCC are one of very important device to produce high quality electrical products such as cell phone, etc. Quality and reliability of MLCC are corresponding to not only average dielectric properties but also local fluctuation of them. Furthermore, local fluctuation of dielectric properties of MLCC could evaluate with MIR spectroscopy. It is possible to obtain a satisfied MIR spectrum from small size samples performed by a micro-focus spectrometer combined with synchrotron radiation as a high luminance light source at beam line BL43IR of SPring-8. From the above result, it is possible to evaluate the degree of homogeneity by comparing the shape change of Ti–O peak on IR spectra.

Troglitazone exists as four isomers in equal amount and these isomers compose two racemic compounds, RR/SS and RS/SR. The objective of this study was to discriminate between the racemic compounds and between the crystal and amorphous forms of troglitazone in solid dispersions (SDs) using IR-to-THz imaging. SDs of troglitazone with polyvinylpyrrolidone (PVP, carrier) were prepared by the closed melting method. SDs were heated at various temperatures and water content. The mid-to-far infrared measurements for the powder samples were performed by using the synchrotron radiation source at the BL43IR in SPring-8. Crystalline RR/SS (L) and RS/SR (H) showed different spectra, that is, each form had a specific peak, respectively. However, amorphous forms prepared from each crystalline form exhibited the same spectra. Using the chemo-metric analysis, the existing component was decided in each pixel and the distribution of crystalline L, H and amorphous troglitazone in SDs could be illustrated. For the sample heated at 105 °C, 75%RH, scattered plots of H and amorphous against PVP showed the trend for H was negative; on the other hand, amorphous showed positive correlation. This result suggested that H existed separately, whereas amorphous would be dissolved in PVP. Based on these evaluations, it was clear that the physical state and distribution of troglitazone in SDs, including the discrimination between L, H, and amorphous, reflect the preparation conditions. Chemical imaging can observe a difference in the dispersed state of drug and ingredient in a visible image by performing statistical processing.

Mordenite (structure type MOR) is one of nano-porous crystals of aluminosilicate zeolites. The framework of mordenite has one-dimensional channels along the c-axis. Cations, such as Na, are distributed at the side pockets of channels. We measured polarized far infrared absorption spectra of Na-type mordenite single crystals with the size of less than ∼100 μm. The measurements were performed by the microspectroscopy station of BL43IR at SPring-8. The polarization directions are set for parallel and perpendicular to the c-axis. The polarization dependence is observed clearly in the spectra. Absorption peaks are observed at 140 and 320 cm−1 for parallel polarization and at 170 and 280 cm−1 for perpendicular polarization. They are assigned to the anisotropic motion of Na cations and framework. The spectra are compared with the ordinary absorption spectra of the pellet forms of Na-, Rb- and H-type mordenite powders.

BL43IR of SPring-8 has been constructed for the infrared materials researches, and it covers a wide spectral range from 100 to 20,000 cm −1 . The microspectroscopy station of this BL has a spatial resolution smaller than 10 μm in diameter in the mid-infrared region without apertures. This station had been mainly used within mid-infrared region, and its performance in the far-infrared region had not been tested. In this paper, we examined the capability of the microscope in the far-infrared region and the spatial resolution is found to be almost at the diffraction limit. The microspectroscopy station has been revealed to have a good performance for doing materials researches in all the spectral range available.

The authors report infrared near-field spectroscopy using synchrotron radiation at BL43IR, SPring-8 in the finger print region. At the microspectroscopy station, the infrared synchrotron radiation beam is focused on a cantilever probe with a 3 μm square aperture. A comb-shaped Au electrode with the width of 3 μm and the distance of 3 μm is used for the reflection measurement. The Au electrodes can be resolved at 650 cm−1 and the resolution is estimated to be λ/5.