Measuring device and method for producing and using the same
AssigneeFraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V.
InventorsWolfgang Schade, Martin Angelmahr, Jannis Koch
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Abstract
A measuring device is provided having at least one substrate, which contains or consists of a polymer or a glass, at least one optical waveguide being written in the substrate, in which at least one Bragg grating with a predeterminable grating constant is arranged, wherein the measuring device further includes an evaluation device, which is configured to determine a deformation of the substrate and/or a force acting on the substrate from a change in the grating constant and/or a change in the refractive index of the Bragg grating.
Claims19
A measuring device comprising:
- at least one substrate, which comprises a polymer or a glass, wherein at least one optical waveguide is written into the substrate, in which at least one Bragg grating having a grating constant is arranged;
- and
- an evaluation device configured to determine a deformation of the substrate and/or a force acting on the substrate from a change in the grating constant and/or a change in the refractive index of the Bragg grating, wherein the Bragg grating or the waveguide or both have an elliptical cross-section, and a longer axis of symmetry of the elliptical cross-section is arranged at a fixed angle to the normal vector of the plane defined by the substrate.
A method for detecting a deformation and/or an acting force, the method comprising:
- providing at least one substrate, the at least one substrate comprising a polymer or a glass, wherein at least one optical waveguide is integrated in the substrate and wherein at least one Bragg grating having a grating constant is arranged in the waveguide, wherein the Bragg grating or the waveguide or both have an elliptical cross-section, and a longer axis of symmetry of the elliptical cross-section is arranged at a fixed angle to the normal vector of the plane defined by the substrate;
- applying a force to the substrate;
- and
- detecting a deformation of the substrate and/or a magnitude of the force acting on the substrate from a change of the grating constant of the at least one Bragg grating.
A method for producing a measuring device having at least one substrate which comprises a polymer or a glass, wherein at least one optical waveguide is written into the substrate, in which at least one Bragg grating having a grating constant is arranged, wherein the Bragg grating or the waveguide or both have an elliptical cross-section, and a longer axis of symmetrie of the elliptical cross-section is arranged at a fixed angle to the normal vector of the plane defined by the substrate,
- said method comprising:
- providing a substrate having a first refractive index, irradiating the substrate with laser radiation forming a focal point in the substrate and having a pulse length from about 50 fs to about 500 fs;
- moving the substrate perpendicular to the laser beam to carry out a first irradiation, said first irradiation creating a waveguide core in the irradiated volume of the substrate, said waveguide core having an increased refractive index compared to the first refractive index;
- re-irradiating a part of the waveguide core with said laser radiation so that a plurality of partial volumes are formed in the waveguide, which have an increased refractive index compared to the waveguide core and which form a Bragg-grating.
Dependencies are inferred from the claim text.