Influence Of Samarium Filter On The Performance Of Nd:YAG, Cr:Nd:GSGG and Er:YAG-Lasers

Since solid state laser, especially Nd:YAG laser, find more and more applications in the medical and industrial field, methods to improve the efficiencies of these systems are under discussion again. Among these, cavities and flow-tubes made of so called "fluorescence-converting" materials face some special attraction. They can be used without a major redesign or reconstruction of the laser head, just replacing the corresponding parts. In our work the performance of Samarium doped glass is evaluated, which has absorption bands in the UV spectral region and fluorescence bands in the visible region, close by or at the absorption bands of Nd:YAG laser crystals. In this way unused or even harmfull UV radiation could be transferred and should intensify the pumping. By measuring the relevant spectra of flashlamps and arclamps with and without the Samarium doped filter glass in a laser cavity we try to clarify this process. We examine the thermal lensing of the different laser rods (Nd:YAG, Cr:Nd:GSGG and Er:YAG) under both conditions and determine the output power or energy for different pump powers or energies respectively.