Recent progress in planar waveguide spectrometers

In this invited paper we introduce several types of waveguide spectrometers. We present a high-resolution 50-channel AWG spectrometer, including its use to interrogate a fibre Bragg grating sensor with a high wavelength accuracy of 1 pm. A 40-channel AWG operating in a broad wavelength range of 1250-1550 nm is introduced. We present a new 15-channel CWDM demultiplexer using a single curved Si-wire waveguide with an etched sidewall grating and chip size of only 90 μm × 140 μm. Finally, the first planar waveguide Fourier-transform spectrometer is pres