Visible Diode Laser Systems, Apparatus and Methods of Use

Abstract

Systems, apparatus and methods for performing laser operations in boreholes and other remote locations, such operations including laser drilling of a borehole in the earth. Systems, apparatus and methods for generating and delivering high power laser energy below the surface of the earth and within a borehole. Laser operations using such downhole generated laser beams.

1 - 16 . (canceled) 
     
     
         17 . A method of generating a high power laser beam, the method comprising:
 a. providing electrical power to a plurality of laser units located in a borehole, each laser unit comprising a plurality of diode lasers;   b. the laser units located in a cavity defined within a laser source assembly;   c. the laser diodes 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 beamlets paths;   d. transmitting the initial laser beamlets along the laser beamlet paths into a beam transformation system;   e. the beam transforming system changing a direction of the initial laser beamlets;   f. the beam transforming system reducing the spacing between the initial laser beamlets;   g. cooling the laser units; whereby the laser units temperature during generation of the laser beamlets is kept below 80° C.,   h. forming an operational laser beam;   i. directing the operational laser beam to a target in the borehole to perform a downhole laser operation.   
     
     
         18 . The method of  claim 17 , 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 200. 
     
     
         19 . The method of  claim 17 , wherein the operational beam has a power of greater than 5 kW and an M 2  of less than 100. 
     
     
         20 . The method of  claim 17 , 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 100.