1. See for example:https://www.alliedmarketresearch.com/sensor‐marketforworld sensors market at ~US$150Bn per annumandhttps://www.marketstudyreport.com/request‐a‐sample/1175913on current fibre sensors markets at ~US$1 Bn per annum.
2. Principles of Chemical Sensors
3. A Flexible Fibrescope, using Static Scanning
4. The fotonic sensor;Menadier C.;Instrum. Control Syst.,1967
5. And for interferometry:Snitzer E.Apparatus for controlling the propagation characteristics of coherent light within an optical fibre. US Patent 3 265 589 filed 19 August 1969.