【摘要】 通过控制平台移动速度来控制紫外曝光量和2次曝光的方法实现任意变迹光纤布拉格光栅的制备.该方法采用连续氩离子激光作为紫外光源,不需要光强掩模板,通过对移动平台速度的编程控制可以获得任意的光栅结构参数,如长度、变迹包络、平均折射率改变量等.在2次曝光过程中,由于对2次紫外曝光量的精确控制,整个光栅的总平均折射率变化保持不变,从而避免了由此引起的啁啾而可以获得无旁瓣窄带宽的反射光栅.采用该方法制备了一根2cm长的高斯变迹光栅,其反射带宽达到了0.15nm,反射率约为95%.更多还原

【Abstract】 A double-exposure fabrication method without any intensity shadow mask to fabricate arbitrarily apodized fiber Bragg gratings(FBGs)with narrow bandwidth is demonstrated by controlling the total ultra violet(UV) irradiation along the grating by varying the speed of a translation stage.The UV source used is a stable continuous intracavity frequency-doubled argon-ion laser.The parameters(such as length,apodization profile,average index change)of FBGs can be easily changed with this method.The total UV irradiation is kept constant in the double-exposure process because of the precise control of the exposure time,which ensures that the apodized FBG’s bandwidth can be extremely narrow.The full width at half maximum(FWHM) bandwidth of the 2-cm-long apodized FBG fabricated by this method is 0.15 nm with a maximum reflectivity of more than 95%.更多还原