Visible diode laser systems, apparatus and methods of use

1. A high power laser source for generating high power beams in situ in a borehole, the laser source comprising:

a. a downhole assembly having an outer housing, the outer housing defining a first cavity, a length and an axis;

b. a cooling assembly in thermal contact with the first cavity:

c. a semiconductor laser module assembly located in the first cavity, the semiconductor laser module assembly comprising: an outer wall defining a second cavity;

d. a plurality of laser units located in the second cavity, each laser unit in thermal contact with the cooling assembly; each laser unit comprising a plurality of diode lasers;

e. the laser diodes configured in the laser units, wherein the laser diodes are capable of generating a plurality of initial laser beamlets, wherein the initial laser beamlets from the laser units have substantially parallel beamlet paths and a spacing between the beamlet paths;

f. the laser units configured in the second cavity, whereby the substantially parallel beamlet paths are directed toward a beam transformation system;

g. the beam transformation system containing optics, wherein the beamlet paths are directed in a direction substantially parallel to the axis, and wherein the spacing between the beamlet paths is reduced; and,

h. a focusing optics package, wherein an operation laser beam is formed.

2. The laser source of claim 1 , wherein the laser beamlets from each laser unit have a total power of greater than 10W, a wavelength from about 400 nm to about 900 nm, and an M 2 of less than 100.

3. The laser source of claim 2 , wherein the operational beam has a power of greater than 5 kW and an M 2 of less than 50.

4. The laser source of claim 2 , wherein the operational beam has a power of greater than 10 kW and an M 2 of less than 20.

5. The laser source of claim 2 , wherein the operational beam has a power of greater than 10 kW and an M 2 of less than 20, and a wavelength from about 400 nm to about 500 nm.

6. The laser source of claim 2 , wherein the operational beam has a power of greater than 10 kW and an M 2 of less than 20, and a wavelength from about 500 nm to about 600 nm.

7. The laser source of claim 1 , wherein the laser beamlets have a power of greater than 0.25 W, a wavelength from about 400 nm to about 900 nm, and an M 2 of less than 50.

8. The laser source of claim 7 , wherein the operational beam has a power of greater than 5 kW and an M 2 of less than 20.

9. The laser source of claim 1 , wherein the initial beamlet paths are substantially normal to the axis.

10. The laser source of claim 1 comprising a source of electrical power, wherein the electrical power source lowers an incoming voltage and increases an current to provide a transformed electrical power to the laser units.

11. The laser source of claim 7 comprising a source of electrical power, wherein the electrical power source lowers an incoming voltage and increases a current to provide a transformed electrical power supply to the laser units; wherein the incoming voltage is from about 400V to 1,000V and the incoming current is from about 40 A to 100 A; and the transformed electrical power supply has a voltage of from about 80V to 300V and a current of from about 80 A to 300 A.

12. A system for generating a high power operational laser beam in situ in a borehole, the system comprising:

a. a mobile field unit, the mobile field unit comprising a control unit, a cooling system, conveyance structure, the conveyance structure having a proximal end and a distal end;

b. the conveyance structure comprising a line structure, a cooling fluid delivery line, and an electrical power line;

c. a downhole assembly in mechanical, fluid and electrical association with the distal end of the conveyance structure, whereby electrical power and cooling fluid can be supplied to the downhole assembly;

d. the downhole assembly having an outer housing, the outer housing defining a first cavity, a length and an axis;

e. a cooling assembly located in the first cavity, the cooling assembly having a cooling fluid flow channel, the fluid flow channel in fluid communication with the conveyance structure fluid delivery line;

f. a semiconductor laser module assembly located in the first cavity, the semiconductor laser module assembly comprising: an outer wall defining a second cavity;

g. a plurality of laser units located in the second cavity, each laser unit in thermal contact with the cooling assembly; each laser unit comprising a plurality of diode lasers;

h. the laser diodes configured in the laser units, wherein the laser diodes are capable of generating a plurality of initial laser beamlets, wherein the initial laser beamlets from the laser units have substantially parallel beamlet paths and a spacing between the beamlet paths;

i. the laser laser units configured in the second cavity, whereby the substantially parallel beamlet paths are directed toward a beam transformation system;

j. the beam transformation system containing optics, wherein the beamlet paths are directed in a direction substantially parallel to the axis, and wherein the spacing between the beamlet paths is reduced; and,

k. a focusing optics package, wherein an operation laser beam is formed.

13. The laser source of claim 12 , wherein the laser beamlets from each laser unit have a total power of greater than 10 W, a wavelength from about 400 nm to about 900 nm, and an M 2 of less than 100.

14. The laser source of claim 12 , wherein the operational beam has a power of greater than 10 kW and an M 2 of less than 20, and a wavelength from about 400 nm to about 500 nm.

15. The laser source of claim 12 , wherein the operational beam has a power of greater than 10 kW and an M 2 of less than 20, and a wavelength from about 500 nm to about 600 nm.

16. The laser systems of claim 12 , wherein the cooling system comprises an aqueous coolant, and has the capability to flow the coolant at a flow rate of at least about 2 gpm.