The program objectives are to develop a reliable, compact, flexible, erbium garnet (Er:YAG) laser for surgery. The Er:YAG laser operates at 2.94 micron wavelength, an ideal wavelength for laser ablation of tissues since it matches the hydroxyl absorption. Past research on the Er:YAG laser in the Soviet Union, where it was invented, coupled with subsequent US work, has shown Er:YAG crystals are easily grown and optimized for laser performance. However, problems still exist in damage to optical components by the 2.94 micron laser beam, excessive heat produced by flashlamps requiring external water cooling, and pulse control of the laser. We propose an Er:YAG laser system operating in a continuous (CW) mode pumped by semiconductor laser diodes, instead of the bulky and inefficient flashlamps. This design improves the efficiency, size, weight and reliability of the Er:YAG laser design will eliminate infrared fiber delivery, and external water cooling. CW operation of this system enhances coagulation by the Er:YAG laser and eliminates laser damage to optical components. This laser has significant applications in delicate surgeries, where small cut depths and volumes are important, and has direct commercial application as a medical product.
