Development of Sandglass Shape FBG Sensor to Reduce Cross Sensitivity Effect

Table 1

Etching rate of HF solution with different concentration.

HF : H2O (Molar Ratio)	4 : 1	3 : 1	2 : 1	1 : 1	1 : 2	1 : 3
Corrosion rate (um/h)	4.8	5.75	10.75	16	23.2	49