色散补偿光栅切趾强度对光谱特性影响的研究

Study of the impact of apodization sharpness on spectral response for dispersion compensating gratings

切趾强度的概念证明了在线性啁啾色散补偿光栅中切趾强度对光谱特性的影响远大于切趾包络函数本身。将其用于典型的色散补偿系统,通过逐步改变切趾强度对比了三种切趾包络函数:余弦、柯西和汉明函数的光谱响应。研究发现,由于切趾强度的影响,所有的切趾包络函数都具有近似的趋势。当切趾强度参数约为0.75时,色散均值与理想色散之间的偏离量最小,群时延影响较小,反射带宽较大,且光栅长度较短。结果表明,最佳色散强度参数为0.75,此时有最好的光谱特性。

A apodization sharpness parameter is defined.The effect of different apodization sharpness on the spectral response is compared.It is demonstrated that the apodization sharpness parameter plays a more important role in the behavior of the mean dispersion,group delay ripple and some other spectral responses even than the type of apodization profile itself.The spectral response of three apodization function Cosine,Cauchy and Hamming are compared,with the apodization sharpness parameter is changed gradually.The results show that an apodization parameter is about 0.75 in better spectral response,minimum group delay ripple impact,minimum deviation from the required dispersion value.