Alcoz J J, Lee C E, Taylor H F
Dept. of Electr. Eng., Texas AandM Univ., College Station, TX.
IEEE Trans Ultrason Ferroelectr Freq Control. 1990;37(4):302-6. doi: 10.1109/58.56491.
A fiber-optic ultrasound sensor is presented. The sensor consists of a continuous length of single-mode optical fiber with a built-in Fabry-Perot interferometer. The acoustic pressure produces changes in the index of refraction along the interferometer cavity through the strain-optic effect, thus modulating the reflected power of the light propagating in the fiber. The dielectric internal mirrors that form the interferometer are fabricated by joining a fiber coating with a TiO(2) film at one end to an uncoated fiber by electric arc fusion splicing. Experimental results have been obtained for sensors embedded in plastic and graphite composite materials, using ultrasound waves in the range from 100 kHz to 5 MHz. Values for the optical phase shift amplitude as large as 0.5 rad were obtained at an acoustic frequency of 200 kHz for a 1.1-cm-long interferometer embedded in plastic.
介绍了一种光纤超声传感器。该传感器由一段连续的单模光纤组成，内置法布里-珀罗干涉仪。声压通过应变光学效应使沿干涉仪腔的折射率发生变化，从而调制在光纤中传播的光的反射功率。形成干涉仪的介质内反射镜是通过电弧熔接将一端带有TiO(2)薄膜的光纤涂层与未涂层光纤连接而成。对于嵌入塑料和石墨复合材料中的传感器，在100kHz至5MHz范围内使用超声波获得了实验结果。对于嵌入塑料中的1.1厘米长的干涉仪，在200kHz的声频下获得了高达0.5弧度的光学相移幅度值。
