Skip to Main Content
For the application of a long-period waveguide grating (LPWG) to a refractive index (RI) sensor, its RI sensitivity is experimentally investigated. The characteristics of the LPWG made of thermocurable polymers are observed when individual liquids with different RIs cover its cladding surface. They are sensitive to the RI of liquid. For the transverse-magnetic mode, the center wavelength of a resonance band increases by 77.7 nm as the RI of liquid increases from 1.0 to 1.47. The experimental results indicate that the LPWG may be used as an RI sensor.