Turn-around point long period fiber gratings (TAP-LPFG) are designed by simulations and fabricated by CO2 laser point-to-point irradiations. It is found that the transmission power of a TAP-LPFG exhibits a large linear range with high sensitivity in response to the surrounding refractive index change. The linear power-refractive index relation enables an intensity based refractive index sensor with significantly simplified calibration and instrumentation. By choosing the grating period, the TAP-LPFG can be designed to operate in different refractive index ranges. The TAP-LPFG sensors are demonstrated for detection of sucrose solutions, refractive index matching liquids and low concentration glucose solutions. Compared with the traditional wavelength-shift based measurement method, intensity based TAP-LPFG sensors may provide a cost effective solution for fast and in situ detection of refractive index changes.
National Science Foundation (U.S.)
- Cost-effective solutions,
- Glucose solution,
- Grating periods,
- High sensitivity,
- Intensity-based,
- Linear range,
- Long period fiber grating,
- Low concentrations,
- Measurement methods,
- Optical fiber sensor,
- Refractive index changes,
- Refractive index matching,
- Refractive index sensing,
- Refractive index sensor,
- Sucrose solution,
- Surrounding refractive indices (SRI),
- Transmission power,
- Turn-arounds, Carbon dioxide,
- Glucose,
- Glucose sensors,
- Lasers,
- Refractometers,
- Semiconductor quantum wells,
- Sensors,
- Sugar (sucrose), Refractive index,
- Intensity based measurement,
- Turn-around point long period fiber gratings
Available at: http://works.bepress.com/jie-huang/81/