Adhesive-assembled fiber-optic interferometer
OwnerRichard Van Neste, Claude Belleville +2inventors
InventorsRichard Van Neste, Claude Belleville, Ninon Belleville, Sylvain Bussiere
Life of this patent
Estimating the term…
Abstract
A method to assemble optical fiber devices and a fiber optic sensor is provided. It features a small adhesive joint between the fiber and a capillary tube by means of a small recess carved on the side of the fiber. This recess acts as a reservoir for the adhesive during the insertion of the fiber inside the tube. Then, the tube is heated so that the adhesive swells out of the recess to make the joint between the tube and the fiber. This method is used to assemble a fiber optic Fabry-Perot interferometer. This interferometer can be used as a sensor for the measurement of a number of physical parameters.
Claims35
An optical fiber device comprising:
- a tube having an inside diameter;
- a first optical fiber for inserting in said tube and having an outside diameter closely matching said inside diameter and a first recess on its outside surface, said first recess for carrying an adhesive material inside said tube;
- and
- said adhesive material for forming a first adhesive joint between said optical fiber and said tube, a location of said adhesive joint along said optical fiber being defined by a location of said recess.
An optical fiber interferometer sensing device for measuring a physical quantity and having a sensitivity comprising:
- a tube having a longitudinal strain to be sensitive to said physical quantity, said tube having an inside diameter;
- a first optical fiber for inserting in said tube and having an outside diameter closely matching said inside diameter, a first reflective surface on an end inside said tube and a recess on its outside surface, said recess for carrying an adhesive material inside said tube;
- said adhesive material for forming a first adhesive joint between said optical fiber and said tube, a location of said adhesive joint along said optical fiber being defined by a location of said recess and at least partly defining said sensitivity;
- and
- a second reflective surface mechanically connected to said tube, said first and said second reflective surfaces defining an interferometer cavity, a length of said interferometer cavity varying with said physical quantity as a result of said longitudinal strain.
A method for bonding an optical fiber in a tube comprising:
- providing a recess on an outside surface of said optical fiber;
- depositing an adhesive in said recess;
- inserting said optical fiber in said tube, an inside diameter of said tube closely matching an outside diameter of said fiber and said adhesive being highly viscous to solid;
- and
- heating said adhesive and an area of said optical fiber and an area of said tube adjacent to said adhesive in order that said adhesive swells out of said recess and creates a bond between said optical fiber and said tube.
An optical fiber interferometer for measuring a physical quantity, the optical fiber interferometer comprising a tube and two optical fibers, inserted in the tube and forming an interferometric cavity, each of the two optical fibers having an outside diameter that closely matches an inner diameter of the tube, and each of the two optical fibers having, at their periphery, a recess comprising an adhesive material, a quantity of the adhesive material being in contact with the fiber and another quantity of the adhesive material being in contact with the inner diameter of the tube, whereby the fiber is attached to the tube, wherein one of the optical fibers is for coupling light to the interferometric cavity.
Dependencies are inferred from the claim text.