用相位掩模法,在圆形掺Yb³⁺双包层光纤上制作了Bragg光纤光栅,并用它作为双包层光纤激光器的输出腔镜,在光栅反射中心波长1055.2nm位置得到了窄线宽的激光输出,FWHM为0.271nm,信噪比约为40dB.这种结构的双包层光纤激光器,在双包层增益光纤和后腔镜间没有连接损耗,减小了双包层光纤激光器体积.用自行制作的等强度梁对作为输出腔镜的光纤光栅做双向应力调谐,实现了激光波长无啁啾调谐输出,调谐范围1051.1～1060.04nm,调谐量达8.9nm,调谐过程中激光3dB线宽基本无变化.

Using the phase mask method ,a fiber Bragg grating is fabricated in the circle shape inner cladding Yb 3+ doped double clad fiber(CDCF).By use of this grating as the output mirror of the CDCFL,the narrow linewidthlaseroperatingwavelength1055.2nmatthereflectcenterofthegratingispresented,FWHMis0.271nmand near 40 dB signal to noise ratio. There isn′t splice lose between CDCF and output mirror,and the bulk of CDCFL is reduced . Using a beam of uniform strength, which is fabricated by ourselves, bi direction chirp free tuning of center wavelengths of the fiber grating is realized, the tuning range up to 8.9 nm is obtained from 1051.1 nm to 1060.04 nm, the output laser 3 dB linewidths didn′t obviously change.