In this talk we discuss the possibility of developing broadband low-pass filters, with windows of transparency in pre-set spectral ranges and high absorption in other spectral ranges. We propose to employ the unique optical properties of metal-dielectric composites near the percolation threshold pc for developing such filters. In the dc regime a metal-dielectric composite acts as a bulk dielectric when the metal concentration p is below pc. At p = pc the composite experiences an insulator-metal transition and it behaves as a conductor for p > pc. Near the percolation threshold there are lots of metal clusters of different sizes and shapes. Exactly at p = pc a metal cluster of any scale can be found in the system because of the self-similarity, fractality, of the system at the transition point.
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