The band diagram of surface plasmons (SPs) on a periodic array of metal holes is investigated in both theory and experiment. The extraordinary transmission through a silver film perforated with hexagonally ordered holes arrays on Si and GaAs substrates is measured. In addition, the transmission is also measured with increasing angle of incidence so that the energy dispersion relations are obtained along the symmetry axis ΓM or ΓK. Furthermore, the influence of the hole size and shape on the transmission spectra are investigated. Finally, the silver film perforated with periodic hole array is fabricated at the back of the QDIP as a filter to select a specific waveband, i.e., 3-5 μm or 8-12 μm, from a broad photodetector response..