System and method for determining changes of an optical fibre
AssigneeSaab AB
InventorsRoy Josefsson, Daniel Eckerström
Life of this patent
Estimating the term…
Abstract
Embodiments of the present invention relate to determining temperature, pressure, strain, or other changes of an optical fibre (250) having Fiber Bragg Grating (FBG) patterns provided in at least one portion (Portion 1) of said optical fibre (250), said optical fibre (250) being connected between a first detector arrangement (210) and a second detector arrangement (220).
Claims17
A method for determining strain changes of an optical fibre (250) having Fiber Bragg Grating (FBG) patterns provided in at least one portion (Portion 1) of said optical fibre (250), said optical fibre (250) being connected between a first detector arrangement (210) and a second detector arrangement (220), wherein said first detector arrangement (210) comprises a first light emitting device (231), a first light detecting device (232) and a first control arrangement (233;
- 500), wherein said second detector arrangement (220) comprises a second light emitting device (241), a second light detecting device (242) and a second control arrangement (243;
- 500), the optical fibre (250) comprises a core and a casing, wherein the length of the core of the optical fibre (250) is longer than the casing of the optical fibre (250);
- the method comprising the steps of:
- emitting (s410) light into said optical fibre (250) in a first direction (D1) from said first detector arrangement (210), receiving reflections from said FBG patterns of such emitted light by said first detector arrangement (210), and processing said reflections for determining a current strain change related to said optical fibre (250);
- on the basis of predetermined criteria, emitting (s440) light into said optical fibre (250) in an opposite, second, direction (D2) from said second detector arrangement (220), receiving reflections from said FBG patterns of such emitted light by said second detector arrangement (220), and processing said reflections for determining a current strain change related to said optical fibre (250).
A system (289) for determining strain changes of an optical fibre (250) having Fiber Bragg Grating (FBG) patterns provided in at least one portion (Portion 1) of said optical fibre (250), the system comprising:
- a first detector arrangement (210) and a second detector arrangement (220) wherein said first detector arrangement (210) and second detector arrangement (220) being connected by said optical fibre (250);
- said first detector arrangement (210) comprises a first light emitting device (231), a first light detecting device (232) and a first control arrangement (233;
- 500);
- said first light emitting device (231) being arranged for emitting light into said optical fibre (250) in a first direction (D1) from said first detector arrangement (210), said first light detecting device (232) being arranged for receiving reflections from said FBG patterns of such emitted light by said first detector arrangement (210), and said first control arrangement (233;
- 500) being arranged for processing said reflections for determining a current strain change related to said optical fibre (250);
- said second detector arrangement (220) comprises a second light emitting device (241), a second light detecting device (242) and a second control arrangement (243;
- 500);
- said second light emitting device (241) being arranged for, on the basis of predetermined criteria, emitting light into said optical fibre (250) in an opposite, second, direction (D2) from said second detector arrangement (220), said second light detecting device (242) being arranged for receiving reflections from said FBG patterns of such emitted light by said second detector arrangement (220), and said second control arrangement (243;
- 500) being arranged for processing said reflections for determining a current strain change related to said optical fibre (250);
- the optical fibre (250) comprises a core and a casing, wherein the length of the core of the optical fibre (250) is longer than the casing of the optical fibre (250).
Dependencies are inferred from the claim text.