【摘要】：近年來,為應對日益嚴峻的水質(zhì)安全問題、食品藥品安全問題以及環(huán)境污染問題,滿足水質(zhì)檢測和環(huán)境監(jiān)測等領域?qū)Ω哽`敏度、低成本的微型便攜式生化傳感器的迫切需求,科研工作者們對光學生化傳感器展開了深入研究。光學生化傳感器除了具有靈敏度高、響應速度快、抗電磁干擾能力強等優(yōu)點,還能工作在傳統(tǒng)生化傳感器無法工作的高溫、高濕、易燃、易爆等惡劣環(huán)境之下,因此引起了廣泛關注。根據(jù)檢測原理和器件結(jié)構(gòu)的不同,光學生化傳感器可分為標記型和非標記型兩類。標記型光學生化傳感器在對檢測物進行標定時很可能會引入不必要的污染或標定物的檢測活性受到影響,從而干擾了測量結(jié)果,并且測試時間較長,設備復雜昂貴。非標記型光學生化傳感器可避免標定物對被檢測物的干擾,且能夠?qū)崟r在線監(jiān)測分析過程。非標記型光學生化傳感器的研究主要集中在光纖生化傳感器、光流控生化傳感器和平面光波導生化傳感器。本文首次提出將待測液體作為長周期波導光柵包層的聚合物長周期波導光柵折射率傳感器,使其作為非標記型傳感器工作。文章首先討論了光波導的研究方法、模式耦合理論以及長周期波導光柵的工作原理,特別是芯層模式和包層模式之間的耦合;其次,針對聚合物長周期波導光柵折射率傳感器的工作特性,分析了芯層傳輸?shù)纳⑶�,推導出芯層波導的單模傳輸條件,仿真計算出芯層模式與包層模式之間的耦合系數(shù),確定長周期波導光柵的周期和長度等參數(shù);再次,在實驗室利用紫外曝光、顯影、磁控濺射、感應離子刻蝕等工藝制作出傳感器樣品;最后,搭建光學測試平臺,利用寬帶光源(1520nm-1610nm)作為輸入,改變作為長周期光柵包層的液體材料折射率,檢測出輸出光譜中不同折射率對應的中心波長漂移量,從而得到傳感器的傳感靈敏度,同時測試了傳感器的溫度敏感特性。實驗結(jié)果顯示:待測液體每改變0.002的折射率,相應的中心諧振波長移動18.75nm,器件的傳感靈敏度為9375nm/RIU;針對溫度敏感特性,環(huán)境溫度每改變1℃,某一固定待測液體的中心諧振波長會移動1.47nm。
[Abstract]:In recent years, in order to cope with the increasingly serious problems of water quality safety, food and drug safety and environmental pollution, and meet the urgent needs of high sensitivity and low cost micro portable biochemical sensors in the fields of water quality detection and environmental monitoring, Researchers have carried out in-depth research on optical biochemical sensors. In addition to the advantages of high sensitivity, high response speed and strong ability to resist electromagnetic interference, optical biochemical sensors can also work in harsh environments such as high temperature, high humidity, flammability, explosive and so on, which cannot be worked by traditional biochemical sensors. As a result, wide attention has been paid. According to the detection principle and device structure, optical biochemical sensors can be divided into two types: labeled and unlabeled. The labeled optical biochemical sensor may introduce unnecessary contamination or the detection activity of the calibration object will be affected when calibrating the detection object, which will interfere with the measurement results, and the testing time is longer and the equipment is complicated and expensive. The unlabeled optical biochemical sensor can avoid the interference of the calibrated object to the detected object and can monitor the analysis process online in real time. The research of unlabeled optical biochemical sensor is mainly focused on optical fiber biochemical sensor, optical fluidic biochemical sensor and planar optical waveguide biochemical sensor. In this paper, a polymer long-period waveguide grating refractive index sensor using the liquid to be measured as the cladding layer of the long-period waveguide grating is proposed for the first time, so that it can work as a non-labeled sensor. Firstly, the research method of optical waveguide, mode coupling theory and the working principle of long-period waveguide grating are discussed, especially the coupling between core mode and cladding mode. Secondly, according to the working characteristics of polymer long-period waveguide grating refractive index sensor, the dispersion curve of core layer propagation is analyzed, the single mode transmission condition of core layer waveguide is deduced, and the coupling coefficient between core layer mode and cladding mode is calculated by simulation. The period and length of the long-period waveguide grating are determined. Thirdly, the sensor samples are fabricated by ultraviolet exposure, development, magnetron sputtering and induced ion etching in the laboratory. Finally, the optical testing platform is built, and the refractive index of liquid material as a long period grating cladding is changed by using broadband light source (1520nm-1610nm) as input, and the central wavelength drift corresponding to different refractive index in output spectrum is detected. The sensitivity of the sensor is obtained and the temperature sensitivity of the sensor is tested. The experimental results show that the corresponding central resonant wavelength shifts 18.75 nm with the change of refractive index of 0.002, and the sensor sensitivity of the device is 9375 nm / r IU. According to the temperature sensitivity, for each change of ambient temperature 1 鈩，

本文編號：2295287