Efficient optically coupled GaAlAs diode pumped Nd: YAG laser

We report a novel approach for increasing GaAlAs diode optical power output efficiency by utilizing a solid half cylinder for diode index matching and as a pumping cavity reflector. The solid half cylinder is 5cm in diameter and 6.5 cm long and has a refractive index, n = 1.82. Its outside and end surfaces have been optically polished and gold coated. There are two grooves parallel to the diameter separated 5mm apart for bonding diode array and laser rod. The interfaces between the cylinder and diodes were filled by either low melting point high index glass (n = 2.2) or Lens Bond adhesive (n = 1.55). Laser rods were glued on the cylinder by Lens Bond. The use of these adhesive reduces the Fresnel reflection between interfaces and increase diode efficiency. The theoretical improvements for laser pumping rate are 323 percent for n = 1.55 and 517 percent for n = 2.2.