叶绿素荧光检测电路设计  

Design of Chlorophyll Fluorescence Detection Circuit

作　　者：尚云[1] 黄启俊[1] 常胜[1] 马启明[1] 罗军[1] 张晓[1] 

机构地区：[1]武汉大学物理科学与技术学院,湖北武汉430072

出　　处：《测控技术》2015年第3期9-12,共4页Measurement & Control Technology

基　　金：中央高校基本科研业务费专项资金项目(2012202020204);大学生创新创业训练项目(1210486027)

摘　　要：荧光检测法测叶绿素溶液浓度含量具有实时、快速和原位检测等优点。以1 kHz方波作为载波信号,对激发光源进行调制,光源照射叶绿素溶液发出荧光,经光电转换后通过高信噪比的前级放大、二阶带通滤波器、后级放大、有效值检波和16位AD采样,得到的信号再经单片机处理。实验表明叶绿素浓度与荧光强度具有很好的相关性(相关系数R^2>0.99),满足叶绿素溶液浓度检测要求。Fluorescence detection is an effective method in monitoring the content of chlorophyll, which has the advantages of fast detection speed, real time and in situ testing. 1 kHz square wave is used as the carrier signal to modulate excitation light source. After light source irradiation, chlorophyll emits fluorescence. The whole process includes photoelectric conversion, preamp with high SNR （ signal to noise ratio）, second-order band- pass filter, post-amp, RMS value detector, 16-bit AD conversion and microcontroller processing. Experiment in- dicates that the concentratcon of chlorophyll has a good correlation with fluorescence intensity （ coefficient R^2 〉 0.99）, which meets the requirement of chlorophyll potency detection.

关 键 词：荧光检测 叶绿素浓度 小信号放大 信噪比 

分 类 号：TP216[自动化与计算机技术—检测技术与自动化装置]