红外反射式光电传感器弱光检测系统

Infrared reflective photoelectric sensor low light detection system

针对当前弱光检测系统存在的灵活性和抗干扰性差、时延高的问题,提出并设计红外反射式光电传感器弱光检测系统。系统主要功能模块为光采集单元、温湿度采集单元、滤波单元、实时时钟单元和计算机系统,当光源射在红外反射式光电传感器上,其就会依据不同的光强度,输出不同电压,实现弱光数据的采集。温湿度传感器SHT75将弱光检测环境采样之后的模拟量,经A/D转换单元转换为数字量,对数字量进行修正,再利用总线完成和外部数据之间进行交换,实现温湿度采集与共享。利用二阶滤波器作为滤波单元主滤波器,根据动态频谱跟踪法将有效频段之外的噪声实时滤除。采用实时时钟DS1 340对弱光检测系统各个单元运行进行监测。系统开始运行时,计算机向弱光检测系统各个模块发送复位信号,系统各个组成单元进入初始化阶段,光源调整自身强度,达到设定值。光采集单元和温湿度单元分别采集光数据和温湿度数据,通过滤波单元去除干扰信号,最后将采集到的弱光数据返回到计算机系统,完成一次弱光检测。实验结果表明,该系统运行灵活性系数平均为0. 97、抗干扰能力强、时延低,具有可行性。

Aiming at the problems of poor flexibility,anti-interference and high delay of current low-light detection systems,an infrared-reflective photoelectric sensor low-light detection system is proposed and designed. The main functional modules of the system are light collection unit,temperature and humidity acquisition unit,filtering unit,real-time clock unit and computer system. When the light source is incident on the infrared reflective photoelectric sensor,it will output different voltages according to different light intensities,achieving weak Collection of optical data. The temperature and humidity sensor SHT75 converts the analog quantity after the low light detection environment is sampled into a digital quantity by the A/D conversion unit,corrects the digital quantity,and then exchanges with the external data by using the bus to realize temperature and humidity collection and sharing. The second-order filter is used as the main filter of the filtering unit,and the noise outside the effective frequency band is filtered out in real time according to the dynamic spectrum tracking method. The real-time clock DS1340 is used to monitor the operation of each unit of the weak light detection system. When the system starts running,the computer sends a reset signal to each module of the weak light detection system,and each component of the system enters the initialization phase,and the light source adjusts its own strength to reach the set value. The light collecting unit and the temperature and humidity unit respectively collect optical data and temperature and humidity data,remove the interference signal through the filtering unit,and finally return the collected weak light data to the computer system to complete a weak light detection. The experimental results show that the system has an average operating flexibility coefficient of 0. 97,strong anti-interference ability and low delay,which is feasible.