David Miller and his colleagues have explored several different novel approaches for making wavelength-sensitive devices. One class of devices exploits positioning small or thin detectors in standing waves formed by reflection. Such ideas can also be extended to make transform spectrometers, such as those based on scanning Michelson interferometers. Nanophotonic structures intrinsically have wavelength-dependent behavior as a result of interference. This can be exploited a variety of wavelength demultiplexers in “one-dimensional” nanostructures – multi-layer dielectric stacks – and in “two-dimensional” photonic-crystal-like structures. Nanometallic structures combined with photodetection allow compact resonant detectors.