Optical sensing utilises light to detect the presence or absence of objects, distance, displacement, etc. by measuring either wavelength, frequency, or polarization of light. Its applications are truly diverse and range from seismic, fire and wind sensing to autonomous vehicles, robotics, chemical analysis and pathogen detection. Major advantages of an optical solution include reduced energy consumption (multiple distributed passive sensors with a single active interrogator), increased speed, ability to withstand harsh environments and high accuracy. These benefits, give optical sensing an immense technical and commercial potential. The global optical sensing market reached over US${\$}$ 22 billion in 2022 and is expected to rise, at a compound annual growth rate of $10 \%$, to US${\$}$ 62.77 billion by 2033 [1].