采用幅度掩模和程控扫描曝光技术在经过氢载敏化处理的普通单模光纤上研制出了可用于实现掺铒光纤放大器增益谱平坦化的长周期光纤光栅器件。 该器件使掺铒光纤放大器在30 nm带宽上的增益谱波动从±3 dB减小为±0.3 dB, 器件的附加损耗小于0.3 dB。

The erbium doped fiber amplifier (EDFA) gain flattening filters were fabricated by writing long period gratings in hydrogen-loaded standard single-mode fibers using amplitude masks and a properly designed program controlled scanning exposure system. The gain variation of ±3 dB in an EDFA is reduced to ±0.3 dB over a bandwidth of 30 nm and the total extra insertion loss of the device is less then 0.3 dB.