In order to measure modulation spectra in mid infrared we use Bruker spectrometer Vertex 80v together with additional external chamber. Our configuration allows making all measurements totally in Vacuum, which is a big advantage in case of making measurements in mid and far infrared region. By using different position of the mirrors and the detectors it is possibility to make different measurements including photoluminescence (PL). For photoreflectance (PR) fast differential reflectance (FDR) and phototransmittance (PT) measurements halogen or glow bar can be used as a sources of the probing light. The pump beam is provided by the 640 nm line of CUBE laser. Phase sensitive detection of the measured signal is made using a lock-in amplifier. For detection we use InSb and MCT photodiode cooled by liquid nitrogen. Described setup allows covering spectral range up to 17 µm, moreover taking into account additional bolometric detection use, this range can be extended to the terahertz range and even beyond, up to 1000 µm.
