Analysis About The Laser Loss Affected By Thermally Induced Birefringence

With the advantages of high quality beam, high reliability, compactstructure and high efficiency of electro-optic transferability, diode-pumpedsolid-state laser (DPSSL) has attractted widespread interest,and become thefocus of international research in the field of lasers.Especially,the thermallyeffect is the hot spot of the hot spot.Though the percentage of the thermallyinduced birefringence is low,a serious thermally induced birefringencephenomenon can still decrease the output-energy,damage the beam-qualityat high power,which limits the application and development of thehigh-power solid-state laser.By means of the stable heat conduction equation,this paper gives thetemperature distribution of the crystal, establishes the model,and corrects itwith the axial fixed factor,which is a quite factual model. On the basis ofthis,the variation rules of the temperature distribution along with thepumping power,the pumping light radius,the crystal absorption coefficientand the crystal radius is studied.Furthermore,the relationship between the index of refraction of the ordinarylight and that of the extraordinary light is got.Also,the change laws of theoutput-light power loss with the main coefficients of the laser is shown. Theresults showed that:the most important factor affectting the thermallyinduced birefringence is pumping power,and along with its increase thespeed of the laser loss will rise rapidly and then go slowly.The laser loss isthe minimum with a certain.pumping light radius,which is the optimumvalue.The raise of the crystal absorption coefficient will make the laser lossbigger.