数字滤波在光学镀膜宽光谱监控中的应用

使用CCD(电荷耦合器件)进行光学镀膜宽光谱监控过程中,监测信号受外界杂散光干扰、真空室内背景辐射等因数影响,信噪比低,难于准确监控。在对系统前端光路改造的基础上,采用了数字滤波技术对后期数据进行处理,达到信号压噪目的。实验证明该宽光谱膜厚监控系统具有稳定性好、精度较高、响应速度快等优点。

Application of digital filter in optical coating signal monitoring with wideband spectrum

In the monitoring procedure of optical coating with wideband spectrum based on CCD(charge couple device),the signal-to-noise ratio of monitoring signal is too low to accurately be monitored because it is interfered by the factors of stray light,background radiation in vacuum chamber,etc.By rebuilding the beam path of the system and processing the data by digital filter,noise is depressed so that the system of monitoring optical film thickness with wideband spectrum is more stable,more accurate and response faster.