为了实现体布拉格光栅外腔半导体激光器(VBL)的外腔腔内光束合成,研究了长腔长VBL的激光输出特性。采用焦距为25mm的平凸柱透镜作为单管激光二极管(LD)的慢轴准直镜,同时快轴方向体布拉格光栅(VBG)离轴放置,使得VBL的外腔腔长达到约240mm,线宽从自由运转时的1.8nm压窄至0.14nm。在实验中,改变LD的偏振特性,VBL的激光输出特性不变。通过调节VBG温度,该长腔长VBL的激光中心波长从779.18nm到779.75nm连续可调,调谐过程中线宽基本不变。 In order to realize the beam synthesis in the outer cavity of a Bragg grating external cavity semiconductor laser (VBL), the laser output characteristics of the long cavity length VBL were studied. A plano-convex cylindrical lens with a focal length of 25 mm is used as a slow axis collimator for a single tube laser diode (LD) while a fast axis oriented volume Bragg grating (VBG) is placed off-axis so that the outer cavity length of the VBL reaches about 240 mm, Wide from 1.8nm when free-running to 0.14nm. In experiment, changing the polarization characteristic of LD, the laser output characteristic of VBL does not change. By adjusting the temperature of the VBG, the laser center wavelength of the long cavity length VBL is continuously adjustable from 779.18 nm to 779.75 nm, and the line width during tuning is substantially unchanged.