A novel and simple optical chemsensor concept based on cladding etched Bragg gratings UV-inscribed in D-fibre is reported. The sensitisation process of the Bragg structure to the refractive index of surrounding-medium under HF-etching has been investigated. Two etched devices were used to measure the concentrations of sugar solution, giving sensitivity as high as 0.02 nm/%.
- high-sensitivity optical chemsensor
- etched D-fibre Bragg gratings
- sensitisation process
- Bragg structure
- refractive index
- sugar solution
- UV-inscribed D-fibre