讨论了介质薄膜滤波器的色散特点,并推导了单级全通滤波器的理论色散.比较理论色散曲线与实际测量色散曲线,两者吻合较好.但由于单级全通滤波器的色散带宽及斜率不能满足实际所需的色散补偿曲线,因此提出了多级全通滤波器,通过控制级连的单级全通滤波器的谐振波长及反射率,可以增大色散带宽,改善色散斜率,使之满足实用的要求.文中给出了四级全通滤波器的理论色散曲线.

this paper presents the characteristic of the dispersion introduced by thin-film filters, gives the dispersion formula of single-stage optical filter, and analyzes the effect of the structural parameter on the dispersion, and then, gives the tested dispersion graph of the sample, which are consistent approximately compared with the theoretical dispersion. It is concluded that the single-stage optical filter can not meet the demand. So, the multistage optical all-pass filter is brought forward. The theoretical dispersion graph of four-stage optical all-pass filter is presented. it is concluded that the multistage optical all-pass filter can compensate the dispersion introduced by thin-film filters.