Characterization of a Triboluminescent Optical Sensor for DetectingParticlesLeo.Gauthier@jhuapl.edu

摘要

Common sub-millimeter particle impact phenomena range from zero to thousands of joules of impact energy. The physics of impacts are associated with a wide variety of physical phenomena, including the generation of heat, light, and sound. Although higher energy impact events may result in vaporization of the impacted material and other easily detectable effects, lower energy level impacts of interest may occur with little obvious physical effect. Preliminary research with capacitative sensors provided encouraging results for detecting low-energy impacts. However, vibration within the sensor mounting structure interfered with the detection of impact events. Research on triboluminescent phosphors indicated that a thin layer of material could be used to form the basis of an optical sensor to detect small particle impacts without interference from structural vibrations. A ZnS:Mn phosphor was used as the basis for developing a triboluminescent fiber optic sensor to detect small particle impact events. Detection of impacts is accomplished by detecting the optical pulse that is generated by the abrupt charge separation caused by the particle impact within the phosphor. Laboratory-based experiments were performed to capture the operational characteristics of the sensor. The data are used to study the characteristic response, sensor repeatability, and spatial homogeneity of the detection surface. Tests were also performed to identify the energy detection boundary and to assess environmental survivability. Results of these tests are reported in this paper.