| 摘要 |
A polarization insensitive, multilayer planar reflection filter is provided having (I) strong sidelobe suppression, preferably with sidelobe suppression levels in the range of -30 dB to -50 dB, and (ii) minimum width of the filtered bandwidth for the specified sidelobe suppression level. The multilayer planar reflection filter is provided by a multilayer stack by specifying the manner in which the thickness of the individual dielectric layers are to be varied throughout the stack. The resulting universal design formula specifies these layer values for a stack with an arbitrary number of layers, dielectric constant, incident angle, and wavelength. In particular, the layer thickness values of the alternating layer d1(j) in refractive index n0, and d2(j) in refractive index n0+ DELTA n, vary with each period j and are determined to provide a specified central wavelength, sidelobe suppression and minimum filtered band width. The filter is polarization insensitive because the period required for maximum reflection at wavelength lambda 0 is the same for both TE and TM polarized light.
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