Study On Dual Polarization Beat Frequency Active Fiber Laser Ultrasonic Probe

Optical fiber sensor is gradually accompanied by the development of optical communication technology. It becomes one choice of the next generation of sensor with series of advantages. The fiber laser ultrasonic probe is one kind of medical hydrophone based on the optical fiber sensor. The performance of the ultrasonic probe is better than the traditional piezoelectric medical ultrasonic hydrophone so that it has the potential application prospects in the medical hydrophone.This paper analyzes the principle of the fiber DBR laser sensor, and based on this presents the program of the fiber laser ultrasonic probe. Through the experiment, it is demonstrated that the probe has the ability to detect parameter of ultrasound by detecting the output spectra of the beat frequency. Then, a preliminary test to verify performance of the temperature detection demonstrated the potential application in the ultrasound and temperature sensing of this probe.The main work of the paper covers the following aspects:(1) A large number of relevant researches on the optical fiber ultrasonic sensor are carefully studied. Compared with several sensing technology about the optical fiber ultrasonic sensing, the fiber laser probe based on polarimetric heterodyning beat frequency detection is proposed.(2)The theory of the detection of power density, frequency and propagation direction by using the fiber DBR laser ultrasonic probe is analyzed. A series of tests are done to prove the detecting ability of the ultrasonic probe. The comparative experiments of piezoelectric ultrasonic transducer demonstrate the superiority of the fiber laser ultrasonic probe's performance.(3)The detection of temperature using this probe is proved by the theory and the experiment. According to this, the ultrasonic probe can be used to detect the temperature and ultrasound simultaneously in the future work...