在实际使用中,喇曼激光器工作4 年至5 年,其红外激光输出功率会明显下降(下降幅度可达到50% rv 70%) 。本文在理论上阐述了工作气体甲院的漏气现象以及气体光分解反应是激光输出功率下降的主要原因。实验表明,随着甲炕气压的增高,喇曼频移中高阶斯托克斯光将会增强,从而押制一阶斯托克斯光,同时甲炕气体在实验中产生光分解反应并在喇曼窗口产生沉淀污染,这些均极大地降低了输出激光的效率。针对以上问题,考虑提高喇曼盒的制作工艺以提高其密封性能,减少漏气现象,同时加入缓冲气体(如H2 , He , Ar) 以在一定程度上抑制甲院的光分解反应。

In the pratical u前, the output power of an infrared Raman la启er will be decreased obviously(up to 50% ~ 70%) after it is used for four or 且ve years. In this paper, it is declared theoretically that the leakage and photolysis reaction of the methane gas used are the the main reasons why the laser output power is decreaβed. The experiment shows that with the increaβe of the pressure of the methane gas, the high order Stokes light will be enhanced and the first order Stokes light will be inhibited in the Raman shift. At the same time, the photolysis reaction of the methane g副can result in the precipitation at the Raman window. To solve these problems, it is necessary to improve the sealing performance of the Raman laser and add buffer gas (e.g. H2 , He, Ar) in the laser so as to i出ibit the pl时olysis reaction of the methane gas to a certain extent.