Abstract
A simple intensity modulated displacement sensor is demonstrated using a fused coupler as a probe for measuring glucose concentration in distilled water. It uses a plastic optical fiber (POF) based multimode fused coupler as a probe and a flat mirror as a reflector is captured by the same coupler. The light source is a He-Ne red laser (peak wavelength of 633 nm) which is chopped using a mechanical chopper. The reflected optical signal is detected by the silicon photodiode and the electrical signal is then fed into the lock-in amplifier together with the reference signal of the mechanical chopper. The fiber optic probe is first immersed in de-ionized water to measure the output voltage of a 0 % glucose concentration, followed by liquid with glucose concentrations from 5 % to 25 %. It is found that the peak voltage or the collected light intensity linearly related to the glucose concentration. The sensitivity is measured to be around 0.012 mV/(%) when the glucose concentration is varied from 0 to 25%. It is also observe that the slope of the displacement curve increases linearly with the glucose concentration at a rate of 0.0035 mV/(%)2..
Keywords
Fiber optic glucose sensor, Glucose in distilled water, Coupler probe, Intensity modulation detection.
Citation
M. YASIN, SAMIAN, F. N. AINI, Fiber optic coupler displacement sensor for detection of glucose concentration in distilled water, Optoelectronics and Advanced Materials - Rapid Communications, 10, 5-6, May-June 2016, pp.347-350 (2016).
Submitted at: Jan. 30, 2016
Accepted at: June 9, 2016