Optical pressure sensor with temperature correction

摘要

An optical pressure sensor is disclosed having a pressure sensing optical cavity 22. A temperature sensing optical cavity 24 at the sensor head is used by an interrogator to obtain a pressure signal corrected for effects of temperature. This arrangement provides the advantage that the temperature value to be applied for compensating the sensed pressure is determined at approximately the same location as the determined pressure. The optical cavities may be, for example, Fabry Perot cavities in the sensor head. The pressure sensing cavity and the temperature sensing cavity may be arranged opposite or adjacent to each other and there may be more than one temperature sensing cavity. Multiple optical analysers may be used to detect individually the responses of the pressure and temperature sensing cavities and may operate across multiple wavelengths. The temperature corrected pressure signal may be obtained by iteratively revising first estimates of pressure and temperature.