A model is presented to calculate response nonuniformity in a hybrid mercury cadmium telluride focal plane array in terms of material/
device parameters. The model predicts a minimum 10% intrinsic nonuniformity contribution from the IR detector array caused by compositional variations in detector material with the state-of-the-art HgCdTe material. In hybrid FPAs an additional contribution to the nonuniformity is caused by variations in the charge injection efficiency across the area of the array. The injection nonuniformity contribution can, however, be controlled to negligibly small values by working at very high injection efficiencies, on the order of 99%.