OPTICAL HIGH PRESSURE SENSOR

PRESSURE SENSORS WHICH ARE CURRENTLY AVAILABLE FOR MECHANICAL RESPONE MEASUREMENTS OF PROTECTIVE STRUCTURES EXPOSED TO SEVERE BLAST AND SHOCK ENVIRONMENT HAVE LIMITED BANDWIDTH, ARE SUSCEPTIBLE TO EMI, AND MAY FAIL TO SURVIVE. DIRECT OPTICAL PRESSURE MEASUREMENT COMBINED WITH FIBER OPTIC SIGNAL TRANSMISSION OFFERS THE POSSIBILITY OF AN IMPROVED PRESSURE SENSOR WITH INCREASED BANDWIDTH, EMI IMMUNITY, AND ENHANCED SURVIVABILITY. THE RUBY PRESSURE SENSOR HAS LONG BEEN USED FOR STATIC HIGH PRESSURE MEASUREMENT. IN THIS WORK, WE SEEK TO DEMONSTRATE THE FEASIBILITY OF DYNAMIC HIGH PRESSURE MEASUREMENTS IN RUBY USING THE PRESSURE DEPENDENT SPECTRAL SHIFT OF THE R LINE FLUORESCENCE EVEN THOUGH RUBY MAY NOT BE THE BEST MATERIAL TO USE. THE SENSOR IS INTENDED TO MEASURE DYNAMIC PRESSURE TO 10 KBAR WITH A 1 MHZ BANDWIDTH. THE MAJOR PROBLEM IS TO FIND A WAY TO ACCOUNT FOR TEMPERATURE CHANGES IN THE SENSOR WHICH ALSO AFFECT THE FLUORESCENCE SPECTRUM. THE APPROACH IS TO MEASURE THE FLUORESCENCE AT SEVERAL WAVELENGTHS SIMULTANEOUSLY SO THAT ENOUGH INFORMATION ABOUT THE LINESHAPE IS OBTAINED TO DETERMINE THE PRESSURE AND TEMPERATURE.