In this study, a highly sensitive plastic optical fiber displacement sensor (POF displacement sensor) based on cyclic bending is analyzed both experimentally and numerically. The POF sensor is pressed by cylindrical models without surface damage. Dual bending model is used to increase the sensitivity of the POF displacement sensor. The effects of number of rollers, the distance between top FTY720 buy and bottom plates, and the interval between two rollers on sensitivity of the sensor are discussed.2.?POF Displacement Sensor DesignIn this study, a highly sensitive POF displacement sensor based on cyclic bending is proposed. Figure 1 shows the experimental setup used to measure the power losses of a cyclic bent POF sensor. As shown, the arrangement includes POFs, a cycling bending model, and an optical power meter (Photom, Inhibitors,Modulators,Libraries model 205A) with a detector and a light source.

In the experiments, the illumination source used is a light-emitting diode (LED) with a central Inhibitors,Modulators,Libraries wavelength of 660 nm. Inhibitors,Modulators,Libraries The launch NA of the LED is 0.5. As we know, when light goes through a cyclic bent POF, the power loss occurs. The POF specimen used is a step index type SH-4001 fiber (Mitsubishi Rayon Company Ltd.) with a coating diameter of 2.2 mm, a cladding diameter of 1 mm, a core diameter of 0.98 mm, and a numerical aperture (NA) of 0.5. The refractive index of core and cladding are 1.492 and 1.402, respectively. The core, cladding and coating of these POFs are fabricated from polymethyl methacrylate (PMMA), fluorinated polymer and low-density polyethylene (LDPE), respectively.

Figure 1(a,b) shows the configuration of a POF specimen subjected to one cyclic bending and dual cyclic bending, respectively. In the Inhibitors,Modulators,Libraries following, they are named as one cyclic bending POF sensor and dual cyclic bending POF sensor, respectively. The dual cyclic bending model is used to improve the sensitivity of the sensor. The first cyclic bending route is from the light source to the one-half cylinder. The second one is from the one-half cylinder to the light detector.Figure 1.Experimental setup used to measure power loss in cyclic bending POF sensor.The geometrical model of the POF displacement sensor is shown in Figure 1(c). The parameters studied include the number of rollers (RN), the interval between two rollers (Iroller) and the distance between the two pressing plate (d).

As shown in Figure 1(c), the smallest interval in the bending model is limited to 9 mm. If the smallest interval is used in this model, the fiber will sustain a larger plastic deformation and this may result in damage to the core surface. In addition, a larger interval will Dacomitinib result in a smaller power loss. In order to investigate the effect of interval on the power loss and avoid smaller power loss, three intervals, i.e., 12 mm, 14.5 mm and 18 mm are discussed in this study. In order to investigate the sensitivity of the www.selleckchem.com/products/U0126.html POF sensor, different numbers of rollers, from four up to seven, are employed in this study.