Tunable substrate emission quantum cascade laser array device

The invention discloses a tunable substrate emission quantum cascade laser array device. The tunable substrate emission quantum cascade laser array device includes a substrate, an array device which comprises a plurality of DFB laser units each of which is provided with a ridged waveguide structure, a silicon dioxide layer which covers the entire surface area of the ridged waveguide structures, a front-surface electrode layer which is grown on the silicon dioxide layer and Prague gratings, electrical isolation trenches which are located between the ridged waveguide structures of every two adjacent DFB lasers in the array device, a back-surface metal electrode layer which is grown the lower surface of the substrate, and light exiting windows which are located at the lower surface of the substrate; a lower waveguide layer, a lower limiting layer, an active area, an upper limiting layer, an upper waveguide layer, a cover layer and a highly-doped layer are sequentially grown on the upper surface of the substrate; the highly-doped layer on the ridges of the DFB laser units are provided with secondary sampling Prague grating structures; different Prague gratings have different sampling periods; and the ridged waveguide in each DFB laser unit in the array device is corresponding to one light exiting window.