Optical fiber mode scrambler

Patent metadata

Field	Value
Publication number	US-10401567-B2
Application number	US-201716074937-A
Country	US
Kind code	B2
Filing date	Feb 3, 2017
Priority date	Feb 5, 2016
Publication date	Sep 3, 2019
Grant date	Sep 3, 2019

Abstract

An optical fiber mode scrambler adapted to give a determined bending to an optical fiber inserted in the mode scrambler, the mode scrambler having a general extension direction X, the mode scrambler having a morphology adapted to give the optical fiber a direction along X at the entry of the scrambler, and then to bend the fiber to bring the fiber substantially in the X, Y plan in the −X and Y directions, before bringing the fiber in a rotation around the X axis substantially in the Y, Z plan in the anti clockwise direction for one full rotation, and then bending the fiber to bring the fiber substantially in the X, Y plan in the −X and −Y directions, and then bending the fiber to give the optical fiber a direction along X at the exit of the scrambler.

First claim

The invention claimed is:

1. An optical fiber mode scrambler adapted to give a determined bending to an optical fiber inserted in the mode scrambler,
the mode scrambler having a general extension direction X,
the mode scrambler having a morphology adapted:
to give the optical fiber a direction along X at the entry of the scrambler,
and then to bend the fiber to bring the fiber substantially in the X, Y plane in the −X and Y directions,
before bringing the fiber in a rotation around the X axis substantially in the Y, Z plane in the anti-clockwise direction for one full rotation,
and then bending the fiber to bring the fiber substantially in the X, Y plane in the −X and −Y directions,
and then bending the fiber to give the optical fiber a direction along X at the exit of the scrambler,

the mode scrambler comprising:
a central portion having a peripheral wall,
a first lateral flange and a second lateral flange,

the central portion being positioned between the two lateral flanges,
each lateral flange comprising:
a plate with a first side and a second side, the second sides facing each other and facing the central portion,
a cylindrical hub extending from the first side of each plate in a direction substantially perpendicular to the plate and which is parallel to the extension direction, the hub having a wall and an end opposed to the first side, the end of the hub being partially clogged with a hole,
a first through bore being provided in the wall of the hub,
a second through bore being provided in the plate, the second through bore being located radially outward of the plate around the hub.

2. The mode scrambler according to claim 1 , wherein the central portion is a cylinder, with two extremities, each extremity of the cylinder being brought into contact with a second side of a plate, the central portion being mounted between the two flanges by fixing the two flanges together.

3. The mode scrambler according to claim 1 , wherein there is an adjustable clearance for the mounting of the central portion with the two flanges adapted to tune the optical characteristics of the mode scrambler device.

4. The mode scrambler according to claim 1 , wherein the first flange comprises several screw through bores, the second flange comprises at least the same number of screw through bores at the corresponding positions in the plane, the central portion comprising at least the same number of screw through bores in positions in the plane adapted to be aligned with the screw through bores of the first flange and of the second flange, in order that screw and nuts could be used to fix together the two flanges and the central portion.

5. The mode scrambler according to claim 1 , wherein the first flange and the second flange are set together around the central portion by interlocking.

6. The mode scrambler device according to claim 1 , wherein the first through bore and the second through bore projected in the plane of the plate are angularly separated with respect to the hub axis by an angle comprised between 45 and 180 degrees.

7. The mode scrambler device according to claim 1 , wherein the first through bore is elongated along the X direction.

8. The mode scrambler device according to claim 1 , wherein the plate of the flange is circular, the hub extending from the center of the plate, the second through bore being elongated along the circumference direction of the plate.

9. The mode scrambler device according to claim 1 , wherein the hub is closed off by a plug, the hole being open in the plug.

10. The mode scrambler device according to claim 1 , wherein the device has at least one of the following features:
the dimension of the diameter of the plate of the flange is between 6 cm and 8 cm,
the diameter of the hub is between 1.5 cm and 2.5 cm, and
the hub is between 4 and 5 cm long along the X direction.

11. The mode scrambler device according to claim 1 , wherein the central portion is between 0.3 cm and 0.7 cm thick.

12. System adapted to transform a Gaussian light profile in a top-hat light profile, the system comprising:
a mode scrambler device according to claim 1 ,
an optical fiber having a proximal end and a distal end opposed to the proximal end,
a laser light source adapted to deliver a Gaussian light profile,

the proximal end of the optical fiber being connected to the laser in such a way that at least part of the light emitted by the laser enters the optical fiber, wherein the distal end of the fiber enters through the hole of the first flange inside the hub along the X direction, goes from the inside of the hub toward the outside of the hub through the first through bore, before being bent to be inserted in the second through bore toward the cylindrical central portion, the fiber rotating along the peripheral wall of the central portion, the fiber being bent to go through the second through bore of the second flange and then through the first through bore in the hub and then in the hole to exit from the hub along the X direction, the position of the second through bores being such that the optical fiber does one full turn along the wall of the cylindrical central portion.

13. System according to claim 12 also comprising a detector.

14. The mode scrambler device according to claim 6 , wherein angle is about 90 degrees.

15. The system of claim 13 , wherein the detector is a beam profiling camera connected on the optical fiber, the beam profiling camera being adapted to capture the spatial intensity profile of the laser beam at a particular plane transverse to the beam propagation path.

Assignees

• Inst Nat Sante Rech Med
• Univ Lille Ii Droit & Sante
• Centre Hospitalier Regional Et Univ De Lille Chru
• Univ Lille

Inventors

• Mordon Serge
• Delepôrte Pascal
• Betrouni Nacim

Classifications

• H04B10/2581

  Multimode transmission · CPC title

• G02B6/14 Primary

  Mode converters · CPC title