几种新型LD泵浦Nd∶YAG双频激光器

介绍了几种LD泵浦Nd∶YAG双频激光器 ,均应用双折射原理实现。一类是利用自然双折射效应 ,在激光谐振腔内加入自然双折射元件 ;另一类则是对YAG晶片加压力 ,使YAG晶片本身成为应力双折射元件。由于双折射效应使激光在谐振腔内产生偏振方向互相垂直的寻常光 (o光 )和非寻常光 (e光 )两种成分。因为o光和e光在双折射元件中有着不同的折射率 ,因此一个激光谐振腔变成了具有两个物理长度的谐振腔 ,从而产生双频激光。改变自然双折射元件或对YAG晶片施加的压力 ,可调谐频差。实验中获得 10 9Hz量级的大频差 ,合成波长可到几十毫米 ,适用于绝对距离干涉测量

Several kinds of novel dual-frequency Nd∶YAG lasers pumped by LD

Several kinds of novel dual-frequency Nd∶YAG lasers pumped by LD are described, in which two birefringence principles are applied respectively. One is by inserting natural birefringence elements in the laser cavity to generate double frequencies. The other is by imposing force on Nd∶YAG directly and converting the YAG crystal into a birefringence element to generate the same result. Due to the effect of birefringence, the ordinary light ( o light) and the extraordinary light (e light) which are orthogonally polarized are generated and the phenomenon of laser frequency splitting is resulted. The tunable frequency difference can be obtained by changing the parameters of the natural birefringence elements or changing the force imposed on the YAG crystal. The large frequency difference of 10 9Hz order was obtained in the experiment and composite wavelength of tens of millimeters was gained, so they can be used as the light source for the absolute distance interferometry.