毕业设计（论文）-基于光电位置敏感器新型浓度检测系统的设计.doc

毕业设计(论文)
题目: 基于光电位置敏感器
新型浓度检测系统的设计
学院:电气与电子工程学院
专业:电子信息科学与技术
学生姓名:
指导教师:
毕业设计(论文)时间:二ОО年三月五日~ 六月二十三日共十六周
摘要
目前,实时在线液体浓度检测技术还比较落后,研究开发新型的液体浓度检测系统具有重要意义。浓度的变化会引起液体折射率的变化,对于固定的入射光线,折射率的变化会导致出射光线发生偏移,利用光电位置敏感器件检测出光线偏移量的大小,便可得到液体的折射率,进而计算出液体浓度。基于以上理论,本文首次提出一种双隔离窗的光透射方法应用于液体浓度的检测。
基于光电位置敏感器新型浓度检测系统主要由半导体激光器、光学系统、PSD信号调理电路、单片机系统、A/D转换电路和显示电路组成。由激光器发出激光,经过光学系统照射在一维PSD上,PSD信号调理电路将输出的电流信号进行调理,再由A/D转换电路将模拟量转换为数字量,通过适当接口将其送入8051单片机,单片机对数据处理后,由显示电路显示出待测液体的浓度。
新型浓度检测系统检测方法的准确性在理论分析和实验仿真中得到了验证,一些影响检测结果的主要因素也在本文中作了细致的分析。实验表明,温度漂移和光源强度对本系统的影响非常小。该系统具有结构简单、灵敏度高、稳定性好、响应时间快以及自动化程度高等优点,能够方便、准确地实现液体浓度的实时在线检测。
本浓度检测系统可广泛应用在化工、制糖、食品、制药等诸多行业,是一种具有广阔发展前景的浓度检测系统。
关键词:位置敏感器件(PSD),半导体激光器,液体浓度,8051单片机
Abstract
At present, real-time on-line liquid concentration detection technology is still relatively backward. Research and development of a new type of liquid concentration detection system is of great significance. Changes in concentration can make changes of refractive index in liquid, which will cause exit ray excursion as to the fixed incident ray. Therefore, refractive index will result from ray excursion, whose size can get from using photo-electric position sensitive detectors to detect, thus calculating the concentration of the liquid. Based on the above-mentioned theory, this paper firstly presents light transmission liquid concentration detection system using a double isolated optical transmittance window.
Based on PSD, the new concentration detection system mainly includes the semiconductor laser diode, optical system, and the PSD signal conditioning circuit, SCM system, and A/D converter circuit and display system. Laser issued by the laser machine, via optical system irradiates on the single dimension PSD, then after PSD signal conditioning circuit recuperating the current output signal, the A/D converter circuit will transfer analog into digital, through an appropriate interface into 8051 single chip. After data processing, the display system finally shows the con