초록 ▼

A system and method for initializing and calibrating a fiber optic pressure transducer so that a measured intensity of light which varies as a function of pressure can be accurately translated to the value of pressure which produces that value of light intensity. The transducer includes an enclosed

A system and method for initializing and calibrating a fiber optic pressure transducer so that a measured intensity of light which varies as a function of pressure can be accurately translated to the value of pressure which produces that value of light intensity. The transducer includes an enclosed sensor tip having a diaphragm which is exposed to atmospheric pressure on the inside and the pressure to be determined on the outside as measurements are taken, the resulting pressure differential producing a related attenuation in light intensity. Calibration according to the present invention is performed by exposing the diaphragm to atmospheric pressure on the outside and sub-atmospheric pressure on the inside while transmitting light through the fiber in the usual manner. The sub-atmospheric pressure is changed gradually as simultaneous measurements are made of the intensity of light returned through the fiber and the actual value of the sub-atmospheric pressure at a number of discrete times. The paired values are stored in a look-up table which is subsequently used to determine unknown pressures from matched values of measured light intensity.

대표청구항 ▼

In a fiber optic pressure measurement system having one or more optical fibers extending from a proximal end to a distal end within an enclosed sensor tip, means for directing light of known intensity through the fiber(s) from the proximal to and through the distal end, reflecting means within the s

In a fiber optic pressure measurement system having one or more optical fibers extending from a proximal end to a distal end within an enclosed sensor tip, means for directing light of known intensity through the fiber(s) from the proximal to and through the distal end, reflecting means within the sensor tip for directing at least a portion of the light back through the fiber(s) to the proximal end, and means for attenuating the intensity of the reflected light as a function of the pressure differential across the outside and inside of the sensor tip, means for calibrating the measurement system to establish a known relationship between the intensity of reflected light and pressure differential the calibrating means comprising: (a) means for applying a pressure differential across the outside and inside of said sensor tip; (b) means for varying said pressure differential continuously from a first to a second value over a time period; (c) means for measuring the value of said pressure differential at a plurality of discrete times during said time period; (d) means for measuring the value of the intensity of reflected light at said plurality of discrete times; and (e) means for storing said measured values of pressure differential and intensity of reflected light, whereby a known pressure value may be determined after calibration of the pressure measurement system by matching a measured value of reflected light intensity with the corresponding stored value of pressure differential.