A Study On The Multi-wavelength Drop Analyzer

The multi-wavelength drop analyzer(MWDA)is a new analytical instrument which can analyze the liquid synthetically. The analyzer can measure and discriminate liquids qualitatively and quantitatively by the affections of their physical and chemical parameters. The measurement is operated by monitoring the drop formation process under a certain measuring condition. Comparing with other liquid analysis instruments, MWDA gets more physical and chemical comprehensive parameters directly or indirectly simultaneously. MWDA is the ideal "green instrument" because there isn't any chemical reaction in the testing process; MWDA not only has the strong synthesis testing function, but it is easy for on-line measurement and will be very useful in the liquids measuring fields of environment protection, medicine, drink and so on.The project is supported by the NSTB-MOST Joint Research Program (Project Number: 003/101/04, where NSTB refers to the National Science and Technology Bureau of Singapore and MOST refers to the Ministry of Science and Technology of China). This project aims to design a multi-wavelength drop analyzer (MWDA) based on the fiber-capacitive drop analyzer (FCDA). The purpose of this paper is to advance the sensor configuration, signal acquisition and processing. The sensor configuration and processing circuit are redesigned. The multi-wavelength volume-based fiber drop trace (VFDT) can be shown on the screen of the MWDA, which including more characters of the tested liquid and making it easier when distinguish a liquid from others. On the other hand, it is a base of the MWDA with three or more input optical-source, which is able to improve the discriminating function for more characteristics of the liquid are included in. The main work includes:Improve the drop sensor construction, it conveniences the cleaning processing when the different liquids are tested continuously; the air bubbles in tested liquid are removed by the new construction, too; Modify the fiber signal processing circuit, the single signal optical path is replaced with a multi-optical path so that the more information can be collected and the serviceable range of VFDT is widened;Do experiments with some samples,the VFDT results of the tested liquids are analyzed qualitatively and comparatively.