We compare modulation-transfer-function (MTF) measurements for both mid-wave (MWIR) and long-wave IR (LWIR) bands for an IR-laser scene projector based on the digital micro-mirror device (DMD). We evaluate MTF for both IR-CO2 (10.6 micron) and IR-HeNe (3.39 micron) laser systems. This gives a quantitative image-quality criterion for verifying system performance using identical configurations of the DMD, lens, and screen. Different angles of illumination for the MWIR and LWIR were used, to give an output beam always perpendicular to the DMD. For this experiment a set of bar-target images was used to measure the residual modulation depth at the fundamental spatial frequency of the bars. As expected, the MWIR projector system has better MTF than the LWIR system because of diffraction effects occurring at the 17-micron pixels of the DMD.