IR-WGM-20…IR-WGM-30 and FP318…FP360 have been developed for the spectral ranges of 2.00 − 3.03 μm and 3.04 − 3.60 μm, respectively. The А3В5-based laser heterostructures were grown by LPE MBE and MOCVD techniques in the InAs–GaSb system. The tunable lasers can be applied in DL spectroscopy for measuring the concentration of such industrial and noxious gases as NH4, H2S, HCHO, CH3Cl and others. This type of laser diodes makes it possible to design compact gas sensors with record values of selectivity and sensitivity (at ppb). The models IR-WGM-20…IR-WGM-30 and FP318…FP360 are also promising for medical applications and fiber optics.