1. Techniques for measuring/demultiplexing spectral information from Bragg gratings

To obtain the measurements associated with each of the transducer arrays, or Bragg grating sensors, chained/multiplexed on one or more measurement lines, we need firstly to identify each sensor (its spectral address) and secondly to precisely measure its wavelength (the measurement information). These are the two main roles played by measuring instruments/systems, also known as "readout" systems, which, with rare exceptions, can* interrogate Bragg sensors, whatever their conditioning or the measurand they address, since optically only Bragg filters (transducers) are "seen" by these analysis systems.

In the past, several publications reviewed these techniques...