Development Of The Film Thickness Measuring Instrument Based On Infrared

Polyvinyl chloride, polyethylene, polypropylene and the other plastic films are widely used in industry, agriculture and food packaging and so on, which have many different specifications. The thickness of the finished product is an important indicator of the physical, directly impacting on quality and yield of product, the costs of production and economic benefits. Therefore, On-line System for measuring the thickness of the production in the production process is the important question which is concerned by people, so measurement of the thin film thickness is a base test case on manufacturing industry of thin film.As an instrument of On-line measurement thickness, the ray thickness gauge is the most widely used, but it has shortcomings: radioactive hazard, statistical error , expensiveness and others. But infrared thickness gauge has low price,safeness and reliableness compared to theβ-ray thickness gauge. So in recent years, domestic and international people use infrared technology continuing to develop infrared thickness measurement. In this paper, we use infrared technique to measure the film thickness.The main subject of the work consists of three parts: design of hardware, design of software, debugging and testing. The system is based on principles of infrared transmission method to measure the thickness of film. This includes: the hardware part consists of the measurement component and actuator: the measurement part receives the power values which is through the film; the actuator part make the power meter and light source go along the guide and provide information. The part of software is written by using VC++6.0, it includes: the calibration, parameter setting, measurement, data playback, system maintenance and other functional modules to receive the data from the lower place machine to process and display on the computer.Through the analysis of standard samples of experimental data, we verify the system has some good points including: fast response time, small dynamic error, good accuracy, repeatability and stability; also has advantage of fast response, simple operation and easy maintenance. It brokers through a lot compared with the performance of similar devices and structures, achieves the expected goals. And it totally can achieved industrial production standards.