Tunable-grating external cavity semiconductor laser based on prism beam expanding

The invention provides a tunable-grating external cavity semiconductor laser based on prism beam expanding. A technical scheme is characterized in that a laser diode, a collimating lens and a grating are included; and a prism beam expanding system formed by one or more than one triangular prisms is also included so that the prism beam expanding system carries out dispersion amplification on laser emitted by the laser diode after the laser passes through the collimating lens and before the laser passes through the grating. An incident light angle of each triangular prism is a Brewster angle corresponding to a laser diode wavelength. Emergent light of each triangular prism is vertical to an emergent edge of the triangular prism. In the invention, the prism beam expanding system is added so that a line width of the laser is further narrowed. 本发明提供种基于棱镜扩束的可调谐光栅外腔半导体激光器。技术方案是：包括激光二极管、准直透镜、光栅，其特征在于，还包括个或个以上三棱镜组成的棱镜扩束系统，使得激光二极管发出的激光经过准直透镜后，在经过光栅之前，被棱镜扩束系统进行色散放大。每个三棱镜的入射光角度均为激光二极管波长对应的布儒斯特角。每个三棱镜的出射光匀垂直于该三棱镜的出射棱边。本发明