Apparatuses for coupling radiation out of an optical fiber

Patent metadata

Field	Value
Publication number	US-10830953-B2
Application number	US-201916720270-A
Country	US
Kind code	B2
Filing date	Dec 19, 2019
Priority date	Jun 21, 2017
Publication date	Nov 10, 2020
Grant date	Nov 10, 2020

Abstract

An apparatus for coupling out radiation from an optical fiber, includes a housing, and a stop having a stop opening for delimiting an output coupling angle of radiation that is coupled out of an output end of the optical fiber to a maximum output coupling angle with respect to a central axis of the stop opening, wherein the stop is arranged in the housing. The stop has a stop body made from a transparent material, the stop body has a first total internal reflection face for reflecting radiation that is coupled out of the output end of the optical fiber with greater output coupling angles than the maximum output coupling angle, and the stop body has a second total internal reflection face for reflecting radiation that propagates opposite to the radiation coupled out of the output end and is reflected back by a workpiece.

First claim

What is claimed is:

1. An apparatus for coupling out radiation exiting an optical fiber, the apparatus comprising:
a housing; and
a stop within the housing, the stop comprising:
a stop opening configured to delimit an output coupling angle of radiation that exits an output end of the optical fiber in a propagation direction to a maximum output coupling angle with respect to a central axis of the stop opening, and
a stop body made from a transparent material, wherein the stop body comprises a first total internal reflection face configured to reflect radiation that exits the output end of the optical fiber with greater output coupling angles than the maximum output coupling angle, and a second total internal reflection face configured to reflect radiation that propagates opposite to the propagation direction.

2. The apparatus of claim 1 , wherein the first total internal reflection face of the stop body forms a beam entry face for the radiation propagating in the opposite direction, and wherein the second total internal reflection face of the stop body forms a beam entry face for the radiation that exits the optical fiber.

3. The apparatus of claim 2 , wherein the first total internal reflection face and the second total internal reflection face adjoin one another at a tip of the stop body that delimits the stop opening.

4. The apparatus of claim 1 , wherein the first total internal reflection face is upstream of the second total internal reflection face in the propagation direction of the radiation exiting the optical fiber.

5. The apparatus of claim 4 , wherein the stop body comprises:
a first beam entry face, located opposite the first total internal reflection face, for the entry of the radiation from the output end of the optical fiber into the stop body, and
a second beam entry face opposite the second total internal reflection face for the entry of radiation that propagates in the opposite direction into the stop body,
wherein one or both of the first beam entry face and the second beam entry face extend in a plane perpendicular to the central axis of the stop opening.

6. The apparatus of claim 5 , wherein the first total internal reflection face and the first beam entry face adjoin one another at a first tip of the stop body and the second total internal reflection face and the second beam entry face adjoin one another at a second tip of the stop body.

7. The apparatus of claim 1 , wherein the stop body has a first stop component having the first total internal reflection face and a second stop component having the second total internal reflection face, wherein the two stop components adjoin one another.

8. The apparatus of claim 1 , wherein the stop body is configured in one piece.

9. The apparatus of claim 1 , wherein one or both of the first and the second total internal reflection faces extend rotation-symmetrically with respect to the central axis of the stop opening.

10. The apparatus of claim 9 , wherein one or both of the first and the second total internal reflection faces form a conical face.

11. The apparatus of claim 10 , wherein the first total internal reflection face has a first angle with respect to a plane perpendicular to the central axis of the stop opening of between 10° and 40°.

12. The apparatus of claim 10 , wherein the second total internal reflection face has a second angle with respect to a plane perpendicular to the central axis of the stop opening of between 20° and 60°.

13. The apparatus of claim 1 , wherein the maximum output angle is less than 20°.

14. The apparatus of claim 13 , wherein the maximum output angle is less than 10°.

15. The apparatus of claim 1 , wherein the stop body has at least one beam exit face located radially outside the central axis of the stop opening for the exit from the stop body of radiation reflected at one or both of the first and the second total internal reflection face.

16. The apparatus of claim 15 , wherein the beam exit face is at least partially surrounded by an absorber mounted in the housing.

17. The apparatus of claim 15 , wherein the beam exit face has a scattering effect on the radiation exiting through the beam exit face.

18. The apparatus of claim 1 , wherein the radiation that propagates opposite to the propagation direction results from back reflection by an obstacle.

19. A fiber-optic cable, comprising:
an apparatus for coupling out radiation exiting an optical fiber, the apparatus comprising:
a housing; and
a stop within the housing, the stop comprising:
a stop opening configured to delimit an output coupling angle of radiation that exits an output end of the optical fiber in a propagation direction to a maximum output coupling angle with respect to a central axis of the stop opening, and
a stop body made from a transparent material, wherein the stop body comprises a first total internal reflection face configured to reflect radiation that exits the output end of the optical fiber with greater output coupling angles than the maximum output coupling angle, and a second total internal reflection face configured to reflect radiation that propagates opposite to the propagation direction, wherein the housing forms a connector housing of the fiber-optic cable in which the output end of the optical fiber is at a specified distance from the stop.

20. A processing head for processing workpieces, comprising:
an apparatus for coupling out radiation exiting an optical fiber, the apparatus comprising:
a housing; and
a stop within the housing, the stop comprising:
a stop opening configured to delimit an output coupling angle of radiation that exits an output end of the optical fiber in a propagation direction to a maximum output coupling angle with respect to a central axis of the stop opening, and
a stop body made from a transparent material, wherein the stop body comprises a first total internal reflection face configured to reflect radiation that exits the output end of the optical fiber with greater output coupling angles than the maximum output coupling angle, and a second total internal reflection face configured to reflect radiation that propagates opposite to the propagation direction, wherein the housing forms a processing head housing having a connector holder for holding a connector of a fiber-optic cable, wherein the connector holder is configured for holding the output end of the optical fiber at a specified distance from the stop.

Assignees

• Trumpf Laser Gmbh

Inventors

• Huber Rudolf
• Fuchs Stefan
• Hezel Marius
• Hellstern Julian
• Maier Dominik

Classifications

• G02B5/003

  Light absorbing elements · CPC title

• G02B6/262 Primary

  Optical details of coupling light into, or out of, or between fibre ends, e.g. special fibre end shapes or associated optical elements · CPC title

• G02B5/005

  Diaphragms (for cameras G03B9/02) · CPC title

• B23K26/066

  by using masks · CPC title

• G02B6/4203

  Optical features · CPC title