The chief principles and properties of optical reflection and transmission guided-mode resonance(GMR) filters are presented. These devices are based on GMR effects in dielectric structurescomprising gratings and homogeneous thin films. Detailed characteristics are calculated usingrigorous coupled-wave analysis for bandpass filters operating in reflection and transmission for TE-and TM-polarized incident waves. High resonance efficiency with narrow or wide line-widths isachievable with near-zero reflectance or transmittance side-bands over extended wavelength ranges.To illustrate the potential of this technology, example GMR reflection and transmission characteristicsare presented for filters operating in the visible spectral region. Excellent reflection-filter features arefound when antireflection conditions prevail away from the resonance wavelength. Furthermore,long-range, low side-bands are found to be obtainable for a single-layer GMR reflection filter with aTM-polarized plane wave incident at the Brewster angle. The transmission filter is optimized whenthe structure is highly reflective off resonance. GMR filter fabrication tolerances are discussed withexamples illustrating the sensitivity of the filter center wavelength to variations in layer thickness,grating shape, and incident angle. GMR filters are found to exhibit loss-dependent wavelength shiftssuch that the reflection peak occurs at a different wavelength than the corresponding transmissionnotch. However, under antireflection conditions, the resonance location becomes insensitive to loss.Finally, reflective GMR thinfilm structures that support multiple waveguide modes are studied. Thesedevices exhibit unique characteristic angular and spectral signatures.
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