Attenuated total reflection measuring apparatus capable of Raman spectral measurement

An Attenuated total reflection measuring apparatus that performs Attenuated total reflection measurement by bringing an Attenuated total reflection crystal (ATR crystal) having a refractive index higher than that of a sample into contact with the sample, the apparatus comprising an infrared optical instrument and a Raman spectroscopy instrument, wherein:

• the infrared optical instrument is disposed on the ATR crystal side of the sample, and is provided to irradiate the ATR crystal with an infrared light and collect the infrared light from the ATR crystal;
• the Raman spectroscopy instrument is disposed on a side opposite to the ATR crystal side relative to the sample, and comprises an excitation light source that emits an excitation light, a guide tube having a cylindrical shape that outputs the excitation light from an end of the guide tube to the sample, and a lens portion that is disposed inside the guide tube and collects the excitation light toward the end of the guide tube;
• the end of the guide tube is provided at a position to push the sample to the ATR crystal;
• and
• the Raman spectroscopy instrument further comprises a lens position adjustment mechanism for moving the lens portion along an excitation optical axis of the excitation light, and a spectroscope provided to spectrally disperse a Raman scattering light collected by the lens portion from the sample to detect the spectrally dispersed Raman scattering light.