Complete optical fiber polarization type pressure measurement method and sensing device

Abstract

The invention relates to a full optical fiber polarization type pressure measuring method and a sensing device, which belongs to the optical fiber sensing field. The method comprises the following steps that: the light emitted from a measuring light source passing through an optical fiber for sensing after becoming a linearly polarized light beam and being divided into two orthogonal light beams in polarization; applying pressure on the optical fiber to enable the optical fiber to produce birefringence related with the pressure; respectively measuring the light intensities of the two light beams; determining the size of the pressure on the optical fiber according to the changes of the light intensities of the two light beams. The method provided by the invention introduces the conventional single-mode fiber as a sensing body and adopts a light polarization beam splitter as a polarization characteristic element, thereby simplifying a measuring device, reducing material cost and insertion loss. The device provided by the invention adopts a full optical fiber light path system outside a probe to carry out long-distance signal transmission and ensure the measuring safety.

Description

technical field [0001] The invention belongs to the technical field of optical fiber sensing and industrial automation control; in particular, it relates to the use of laser or light-emitting diode light source, the use of ordinary optical fiber in pressure stress birefringence characteristics, through optical polarization splitting and optical detector measurement, and other optical path devices and circuit analysis systems , complete pressure measurement and pressure sensing. Background technique [0002] Optical fiber sensing technology is a new type of sensing technology that uses light as the carrier and optical fiber as the medium to perceive and transmit external signals (measured). [0003] The principle of optical fiber sensor is actually to study the principle that light is modulated by external parameters. External signals may cause changes in the intensity, wavelength, frequency, phase, and polarization state of light, thereby forming a fiber optic sensor with m...

AI Technical Summary

Problems solved by technology

[0010] 1. The system has many spatial optical devices, complex assembly, large insertion loss, and high error rate;

[0011] 2. The measurement information will be affected by the stress of the optical fiber, so it needs to be transmitted by polarization-maintaining optical fiber, which has high cost and short transmission distance

[0012] 3. It is difficult to separate the probe from the active components;

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