Orbital Angular Momentum-Based Optical Fiber Temperature Sensor With Aberration Immunity and Calibration Exemption

Recently appeared OAM-based interferometers have high requirements on the quality of vortex beam and system calibration, otherwise, the rotational symmetry interferogram will be destroyed. A novel OAM-based optical fiber interferometer with Moir & eacute; techniques for temperature sensing is proposed. A visualized Moir & eacute; probe technique is employed to realize the temperature change indication by rotation calculation. The Moir & eacute; probe achieves immunity to vortex wavefront aberrations and precise calibration exemption. The validation experiments were presented with a comparison to existing OAM-based OFIs. The sensing system with a linear temperature measurement sensitivity of about 29 rad/degrees C with only 0.5 cm PDMS as the sensing part. The temperature measurement resolution is discussed in theory and experiment. The resolution is 7.05*10(-5) degrees C in theory and 0.003 degrees C in experiments.