Fiber optic pressure sensor systems

摘要

The invention is related to numerous improvements for fiber optic measuring systems, and principally those utilizing a deformable diaphragm for sensing pressure. One feature of the invention is particularly oriented to automotive engine combustion chamber pressure measurement. For that application, a sensing tip shielding technique is described using a sintered metal porous plug, which reduces temperature fluctuations experienced at the sensing tip and shields the sensing tip from corrosive materials. A technique for compensation of a fiber optic pressure sensor is also described. In that method, a referencing wavelength is partly reflected and partly transmitted past a filter coating at the sensing end of the optical filament. This technique of the sensor provides improved calibration.