Title :
Scaling CW diode-end-pumped Nd:YAG lasers to high average powers
Author :
Tidwell, Steve C. ; Seamans, Jonathan F. ; Bowers, Mark S. ; Cousins, Ananda K.
Author_Institution :
STI Optronics Inc., Bellevue, WA, USA
fDate :
4/1/1992 12:00:00 AM
Abstract :
The authors analyze the scaling limits of diode-end-pumped Nd:YAG lasers imposed by pumping geometry, thermal distortion, birefringence, and fracture. A scalable 15-W output power diode-end-pumped laser which achieves a 60% slope efficiency is demonstrated. Thermal distortion in this laser is reduced from 2.6 waves to less than 0.15 waves with an aspheric laser rod. Depolarization is reduced by 40 times to less than 0.2% per pass using optical rotators. Modeling results, which accurately predict thermal distortion and birefringence, imply a thermal fracture-limited output power for short end-pumped rods less than 45 W. A dual rod design for an 80-W device is described. One of the four modules in this device has been assembled and tested, producing a CW output of 22.5 W
Keywords :
birefringence; neodymium; optical pumping; solid lasers; thermal stress cracking; 15 W; 60 percent; CW diode-end-pumped Nd:YAG lasers; aspheric laser rod; birefringence; continuous wave output; depolarization; dual rod design; modeling; optical rotators; pumping geometry; scaling limits; slope efficiency; thermal distortion; thermal fracture-limited output power; Birefringence; Diodes; Geometrical optics; Laser excitation; Laser modes; Laser noise; Optical distortion; Power generation; Power lasers; Pump lasers;
Journal_Title :
Quantum Electronics, IEEE Journal of
