Total internal reflection laser tools and methods

• US 9,242,309 B2
• Filed: 02/15/2013
• Issued: 01/26/2016
• Est. Priority Date: 03/01/2012
• Status: Active Grant

• Current Assignee: Foro Energy, Inc.
• Original Assignee: Foro Energy, Inc.
• Inventors: Zediker, Mark S., Faircloth, Brian O., Kolachalam, Sharath K., Grubb, Daryl L.
• Primary Examiner(s): Evans, Geoffrey S
• Application Number:
  US13/768,149
• Publication Number:
  US 20130228557A1
• Time in Patent Office: 1,075 Days
• US Class Current: 1/1
• CPC Class Codes: B23K 26/00 Working by laser beam, e.g. welding, cutting or boring
• CPC Class Codes: B23K 26/0652 comprising prisms
• CPC Class Codes: B23K 26/1462 Nozzles; Features related to nozzles
• CPC Class Codes: E21B 7/15 of electrically generated heat

Abstract

There is provided high power laser tools and laser heads that utilize total internal reflection (“TIR”) structures to direct the laser beam along a laser beam path within the TIR structure. The TIR structures may be a TIR prism having its hypotenuse as a TIR surface.

Claims

1. A total internal reflection high power laser tool, for use in hydrocarbon exploration, hydrocarbon production or the decommissioning of hydrocarbon wells, the tool comprising:

a. a beam tube, defining a tool axis, the beam tube comprising a laser beam path for transmitting a laser beam within the beam tube and a fluid path for transmitting a fluid;

b. a housing in fluid communication with the beam tube, the housing comprising a single and unitary total internal reflection polyhedron structure comprised of a material transmissive to the laser beam; and

, a passage defined in part by a total internal reflection surface of the total internal reflection polyhedron structure, the passage in fluid communication with the beam tube fluid path and removed from the laser beam path;

c. the laser beam path extending through a first surface of the total internal reflection polyhedron structure and into the material;

d. the laser beam path extending to and from the total internal reflection surface and forming an angle of incidence θ

_i on the total internal reflection surface that is greater than a critical angle θ

_c for the total internal reflection surface;

whereby the laser beam traveling along the laser beam path is reflected within the total internal reflection structure by total internal reflection from the total internal reflection surface; and

e. the laser beam path extending from the total internal reflection material and exiting the housing along a straight path;

the exiting laser beam path forming an angle of about 90°

or less with the beam tube axis.

2. The high power laser tool of claim 1, wherein the beam tube defines a beam tube passage and wherein the fluid and laser beam path are within the beam tube passage, whereby the laser beam is transmitted through the fluid in the beam tube passage.

3. The high power laser tool of claim 1, wherein the total internal reflection structure is a right angle prism having a hypotenuse comprising the total internal reflection surface.

4. The high power laser tool of claim 1, wherein the fluid has an index of refraction of n₂ and the material has an index of refraction of n₁, and wherein n₁ is greater than n₂.

5. The high power laser tool of claim 4, wherein the total internal reflection structure is a right angle prism having a hypotenuse and the total internal reflection surface is the hypotenuse.

6. The high power laser tool of claim 4, wherein the housing comprises a nozzle and the laser beam path from the total internal reflection surface extends through the nozzle.

7. The high power laser tool of claim 6, wherein the total internal reflection structure has a tilt of x degrees and the nozzle has tilt of two times 2x degrees.

8. The high power laser tool of claim 7, wherein x is 1.

9. The high power laser tool of claim 7, wherein the total internal reflection structure is a right angle prism having a hypotenuse comprising the total internal reflection surface.

10. A total internal reflection high power laser head for use with a high power laser tool, in hydrocarbon exploration, hydrocarbon production or the decommissioning of hydrocarbon wells, the laser head comprising:

a. the laser head defining a laser head axis;

a total internal reflection structure comprising a first face, a second face and a third face and having an index of refraction n₁ for a laser beam having predetermined beam parameters, the total internal reflection structure defining a total internal reflection structure axis;

b. a laser beam path along which the laser beam travels, the laser beam path parallel with the laser head axis extending through the first face, to the second face and through the third face;

wherein the total internal reflection structure axis is at least 1°

different than the laser head axis, and wherein the laser beam path through the third face forms an angle with the laser beam path through the first face of from about 87°

to about 93°

;

c. the second face comprising a total internal reflection surface; and

,

d. a fluid flow passage adjacent to the second face.

11. The total internal reflection high power laser head of claim 10, wherein the laser beam has a spot size on the first face of less than about 4 cm².

12. The total internal reflection high power laser head of claim 10, comprising a mount, the mount comprising a top window and a side window;

a first wall and a second wall defining a channel;

the channel containing a material having an index of refraction of n₂ for the laser beam;

the material in optical contact with the total internal reflection surface, wherein in n₁ is greater than n₂.

13. The total internal reflection high power laser head of claim 10, wherein the total internal reflection surface has a critical angle θ

_c and the laser beam path forms an angle of incidence θ

_i with the total internal reflection surface; and

wherein θ

_i is greater than θ

_c.

14. The high power laser tool of claim 10, wherein the total internal reflection structure is a right angle prism having a hypotenuse comprising the total internal reflection surface.

15. The total internal reflection high power laser head of claim 14, wherein the material is a air.

16. The total internal reflection high power laser head of claim 10, comprising a prism mount, the prism mount comprising a top window and a side window;

a first wall and a second wall defining a channel;

wherein the second wall comprises the second face;

the channel containing a material having an index of refraction of n₂ for the laser beam; and

the material in optical contact with the total internal reflection surface.

17. The total internal reflection high power laser head of claim 16, wherein n₁ is greater than n₂ and the material is a gas.

18. The total internal reflection high power laser head of claim 10, wherein the laser beam parameters comprise a wavelength of from about 400 nm to about 1,600 nm and a power of at least about 10 kW.

19. The total internal reflection high power laser head of claim 18, wherein the laser beam has a spot size on the first face of less than about 2 cm².

20. The total internal reflection high power laser head of claim 18, wherein the laser beam has a power of at least about 20 kW and the spot size on the first face is from about 0.5 cm² to about 0.08 cm².

21. The total internal reflection high power laser head of claim 20, wherein the material is a gas.

22. The total internal reflection high power laser head of claim 18, wherein the laser beam has a power of at least about 20 kW and wherein the laser beam has a spot size on the first face of at least about 0.08 cm².

23. The total internal reflection high power laser head of claim 22, wherein the material is a fluid.

24. The total internal reflection high power laser head of claim 22, wherein the total internal reflection surface has a critical angle θ

_c and the laser beam path forms an angle of incidence θ

_i with the total internal reflection surface; and

wherein θ

_i is greater than θ

_c.

25. A method of directing a high power laser beam within a laser tool, for use in hydrocarbon exploration, hydrocarbon production or the decommissioning of hydrocarbon wells, the method comprising:

a. directing a laser beam along a beam path to a first surface of a unitary total internal reflection structure in a laser tool;

b. the laser beam traveling along the laser beam path entering the unitary total internal reflection structure through the first surface and traveling along the laser beam path within the total internal reflection structure to a second surface of the total internal reflection structure;

c. the laser beam being reflected by total internal reflection from the second surface and traveling along the laser beam path within the total internal reflection structure to a third surface of the total internal reflection structure;

d. directing the laser beam along the laser beam path from the laser tool; and

,

e. wherein the laser travels along a beam tube, the beam tube comprising a laser beam path for transmitting a laser beam within the beam tube and a fluid path for transmitting a fluid.

26. The method of claim 25, wherein the total internal reflection structure has an index of refraction for the laser beam of n₁;

and comprising providing a fluid having an index of refraction of n₂ adjacent to the second surface, wherein n₁ is greater than n₂.

27. The method of claim 25, wherein the laser beam is transmitted through the fluid as the laser beam is directed from the laser tool.

28. The method of claim 27, wherein the laser beam is transmitted through the fluid as the laser beam is directed to the total internal reflection structure.

29. A total internal reflection high power laser tool, for use in hydrocarbon exploration, hydrocarbon production or the decommissioning of hydrocarbon wells, the tool comprising:

a. a beam tube, defining a tool axis, the beam tube comprising a laser beam path for transmitting a laser beam within the beam tube and a fluid path for transmitting a fluid;

b. a housing in fluid communication with the beam tube, the housing comprising a single and unitary total internal reflection polyhedron structure comprised of a material transmissive to the laser beam; and

, a passage defined in part by a total internal reflection surface of the total internal reflection polyhedron structure, the passage in fluid communication with the beam tube fluid path and removed from the laser beam path;

c. the laser beam path extending through a first surface of the total internal reflection polyhedron structure and into the material;

d. the laser beam path extending to and from the total internal reflection surface and forming an angle of incidence θ

_i on the total internal reflection surface that is greater than a critical angle θ

_c for the total internal reflection surface;

whereby the laser beam traveling along the laser beam path is reflected within the total internal reflection structure by total internal reflection from the total internal reflection surface; and

,

e. the laser beam path extending from the total internal reflection material and exiting the housing along a straight path;

the exiting laser beam path forming an angle of about 90°

or greater with the beam tube axis.