Design and fabrication of narrow-frequency sharp angular filters

The theoretical deduction for the frequency variations of the defect mode and its dependence on the incident angle in one-dimensional defective photonic crystals is discussed. Filters with the dual function of narrow frequency passbands and sharp angular pass breadths in visible and nearinfrared wave bands, in which both the defect mode and the periodic structure are layers of integral times of quarter-wavelengths, were designed. This kind of filter was fabricated with commonly used coating machines.