Patent ID: 11898919
Assignee: INTELLIGENT FIBER OPTIC SYSTEMS CORPORATION
Field: Measurement (Instruments)
Classification: CPC G | IPC G

Claim 0:
1. A method for measuring pressure applied to a first surface of a diaphragm, the diaphragm comprising a common sidewall of a first aperture and a second aperture parallel to the first aperture, the diaphragm having a second surface opposite the first surface, the method operative on a first optical fiber with a first fiber Bragg grating (FBG) attached to a region of changed strain of the second surface upon application of pressure to the first surface of the diaphragm, the second surface having a region of unchanged strain upon application of pressure to the first surface of the diaphragm, the region of unchanged strain thermally coupled to the region of changed strain, the region of unchanged strain also having a second FBG attached to the second surface, the method comprising:
application of a pressure to the diaphragm sufficient to cause a change in a reflected or transmitted wavelength of the first FBG;
measuring a first FBG wavelength and a second FBG wavelength;
converting the first FBG wavelength and the second FBG wavelength into a pressure measurement, and optionally a temperature measurement;
where the converting the first FBG wavelength and the second FBG wavelength into a pressure measurement comprising Pml or Pm2 is one of:

Pm1=C1λ1m1−C1λ01+C2λ2m1−C2λ02 

Pm2=C1λ1m2−C1λ01+C2λ2m2−C2λ02 

where:
C1, C2, λ01 , and λ02 are calibration constants.