Design of On-Line Measurement System of Film Thickness Based on Infrared Technology

摘要

The thickness of the plastic film is an important physical index to the production of plastic. The measurement reslut relates directly to the companies' economic benefit. This paper mainly introduces the digital signal processing in the detection system of film thickness. Through a perfect processing, the system can improve its SNR and finally get a high precision. Firstly, the principle and scheme was presented. After that, this paper mainly introduces the hardware implementation of the system. It includes analog filter circuit, AD sampling and digital filter. With the experimental verification, the system realizes the measurement of the film thickness on-line which can get the precision of micrometer. At present, the equipment has a ready put into use by some companies.