膜厚宽带监控系统中背景噪声的抑制

Research on background noise control and operation technology of thin-film thickness wideband monitoring system

根据CCD器件只适于检测直流或缓变交流信号的特点,基于CCD膜厚监控系统和CCD探测器的强背景噪声环境,利用步进电机的可控、可知性,实现了步进电机与CCD数据采集卡的精确匹配,完成了信号在亮周期和暗周期中的精确采样。结果表明,背景噪声得到了有效的抑制,保证了实测光谱曲线的准确性。

According to CCD suiting to deal with direct current（DC） or slow change alternating current（AC） signal, based on CCD detector working under strong background noise condition in the thin-film thickness wideband monitoring system and the controllability and knowability of stepper motor, the accurate match of CCD data-grabbing-board with the stepper motor was achieved, and the signal of light and dark period was grabbed correctly. The background noise is controlled efficiently. This ensure that the practical spectrum curve is true.