Composition And Testing Of Planner Waveguide Sensor Detection System

Informationization has become a main trend with the development of global Science and Technology. Integrated optics, as an important technigue of informationization is a field which draws intensive research attension both domestically and abroad. Planar optical waveguide, an important research branch of integrated optics provides more solutions in sensor applications.This paper intends to build sensing detection system with a high sensitivity and low cost based on silicon dioxide (SiO2) optical waveguides. The construction of our researches include the construction of testing system, the extraction and identification of measurement signals, which provides a test platform for the development and research of gas sensors, and also lays a foundation for further researches as well.Firstly, we use PECVD (Plasma Enhanced Chemical Vapor Deposition) technique to fabricate the five-layer planar optical waveguide chips. And then we put the optical waveguide chip is placed on the coupling stage, irradiated it with a laser to produce interference fringes, the fringes are measured by a linear CCD (Charge Coupled Device), and measurement data are achieved by curve-fitting running by a C++program.According to the measured results of the optical waveguides, we make the quantitative error analysis on the core thickness, the middle layer thickness, the far field the interference distance of the far field from the optical waveguides. We find that the core thickness and middle layer thickness make a same contribution to the gap of the interference fringes and the far field interference distance is the major factor to produce measurement error. Through the actual error analysis, more accurate results can be achieved by reducing the measurement error generated by the far field interference distance from the error analysis.