基于光电传感器的智能灯控系统的设计

文章设计了一种基于光敏电阻和光电传感器的智能灯控系统.本系统主要包括两部分,一部分是以光敏电阻为主要功能元件的模块,其作为检测系统的启动开关,另一部分则是检测系统,其在晚上对是否有人通过进出口进行探测,并控制灯的亮或熄.一旦光线强度足够低,检测系统启动,然后由光电传感器进行实时探测,并向微控制器发送信号,微控制器对其信...     

激光再制造粉末输送流量检测系统设计

为了检测粉末的流量,设计了一种激光再制造粉末输送流量检测系统,采用电容传感器来检测流量的变化并以2Cr13和H13金属粉末作为输送介质进行了测试试验.结果表明,输送介质为H1粉末的情况下获得较好的检测效果,在粉末的浓度变化大于10-1g/min时具有较好的分辨率.该系统可以用于送粉系统粉末流的检测.     

基于FPGA增量式编码器的接口设计与实现

光电增量式编码器,又称光电角位置传感器,是电气传动系统中用来测量电动机转速和转子位置的核心部件。分析了光电编码器4倍频原理,提出了一种基于可编程逻辑器件FPGA对光电增量式编码器输出信号4倍频、鉴相、计数的具体方法,它对提高编码器分辨率与实现高精度、高稳定性的信号检测及位置伺服控制具有一定的现实意义。经实际项目论证,该...     

感应式循迹小车的设计与实现

传统的循迹小车采用光电传感器作路面轨道检测,其工作可靠性受环境光线的影响很大,实际运行中经常要根据环境光线的变化对传感器的灵敏度进行调整。提出一种感应式循迹小车的设计方法,用金属铝箔胶带代替黑色轨道线,在小车上设置多只金属感应传感器,基于感应的方法来检测铝箔胶带路线的位置,把检测的结果送单片机处理,再由单片机输出相应控制信号驱动小车运行。所提出的方法能够完全消除环境光线对循迹小车的干扰,提高小车运行的可靠性。样品小车的测试结果表明,基于新方法设计的小车运行平稳,在长时间工作中没有出现脱轨现象,小车的整体性能良好。     

基于摩擦纳米发电机的气体流量传感器

气体流量是工农业生产及科学研究的重要控制参数,有必要进行实时测量.基于摩擦纳米发电机研制了一种具有自供电功能的气体流量传感器.传感器在气体流经时产生摩擦起电,从而输出与气体流量呈正比的摩擦电信号,实现自供电式传感,即传感器具有传感器和发电机的双重功能.对传感器的理论输出信号进行了推导建模.实验结果表明,传感器的测量范围...     

脉冲信号测速电路模块设计

基于51单片机的转速测量系统通过光电编码器对电机脉冲信号进行采集,实现对脉冲信号的产生、整形,完成对单片机处理后信息的输出和显示,可对电机转速进行远程控制。键盘模块调节设置初始转速上限,当转速大于上限则声光报警。由于采用了单片机和光电传感器,该系统具有硬件电路简单、测量精度高、性能稳定可靠等优点,适用于自动控制、自动检测及各种转速测量与控制领域。     

简易自动寻迹小车控制器设计

该文主要介绍一种基于单片机的简易自动寻迹小车控制器设计,其硬件主要包括光电传感器介绍与电路设计、两轮驱动介绍与硬件设计以及电源电路设计,软件主要介绍控制方法和策略。该小车采用RPR220光电发射接收一体式传感器根据光线对不同颜色反射红外线强度的不同,来区分白线和黑线,利用LL298N直流电机驱动芯片完成对小车轮的驱动。...     

高精度太阳能跟踪控制器

针对目前采用的传统太阳能跟踪控制器传感器形式单一、抗干扰性差、跟踪精度不高等问题,设计了一种基于可编程逻辑控制器(Programmable Logic Controller,PLC)的太阳能跟踪控制器系统。该系统将固定轨迹粗略跟踪方式与光电传感器精确跟踪方式有效地结合起来,并重点将光电传感器加以改进,从而有效地提高了太阳能利用率。由伺服电机作为执行机构控制太阳能板对太阳位置的跟踪,可以实现对太阳高度角和方位角的双自由度跟踪,使太阳能跟踪装置始终正对着太阳光线位置。通过对比实验表明,该跟踪控制器可以达到较高的跟踪精度。     

基于光电信号控制触发的四路高压脉冲源

给出了一种基于光电信号来作为四路高压脉冲源触发控制的设计原理和方法,采用光电信号作为前级控制触发脉冲,驱动后级高压半导体开关器件（IGBT）输出高压脉冲信号。设计了一台脉冲幅度为500 V~1 k V、脉冲宽度大于500 ns、脉冲前沿小于25 ns以及各通道之间输出的高压脉冲信号分散性小于10 ns的四路高压脉冲源。通过实验结果验证了所采用的设计原理及方法的可行性,给出了单次触发情况下四路高压脉冲输出的实验结果。     

压电微流量阀驱动电源的研究

研究了一种低纹波输出的压电陶瓷驱动电源,实现对压电驱动微流量阀的输出微流量的控制.利用单片机控制数字频率合成芯片来产生各种函数信号,研究了高低压稳压电路、小信号放大处理及功率放大电路,控制信号经滤波、放大及稳压等处理后,函数信号形成高压输出,驱动压电陶瓷,对微流量阀阀芯位移进行驱动,从而实现对微流量阀输出微流量的精密控制.通过对该电源输出特性的试验研究,结果表明,该电源具有良好的输入输出线性特性及低纹波特性,其线性度拟合相对误差仅为84 mV,高压输出纹波电压低于10 mV,这对提高微流量阀输出微流量的控制精度具有重要意义.     

可见光通信感知一体化芯片及关键技术

通信感知一体化是6G关键技术之一。氮化镓量子阱二极管的发射光谱和光探测谱存在重叠区,量子阱二极管光探测器能够吸收具有相同量子阱结构的光发射器件发出的短波长光子,生成光电流。该文基于该物理现象,研制同质集成光发射光接收器件的氮化镓光电子芯片,由于单个量子阱二极管芯片器件自身发光干扰导致感知外界光信号弱,但是收发分离芯片又存在效率低、紧凑性弱、鲁棒性差等问题,将具有相同量子阱结构的量子阱二极管器件制备在同一块芯片上,分别作为发光和接收器件,构建自由空间逆向光通信系统,探索可见光通信感知一体化芯片及关键技术。     

基于可见光通信的一对多视频广播系统

利用自主研发的软硬件搭建了基于可见光通信(VLC )的一对多视频广播系统。通过传输流(TS,transport stream)音视频数据流解决了通信信道 不可靠的问题,通过广播流量控制算法和控制指令的设计解决了多媒体数据广播传输时服务 器和客户端速率不匹配带来的超大缓存需求问题。可见光收发模块采用荧光型LED和PIN探测 器作为光源和探测器。系统拥有蜂窝网络结构,每个蜂窝可以有多个用户,客户可以同时接 收广播信号且不会相互干扰。通过实验实验证了系统的可行性。测试结果表明,本文系统支 持1对多的1080P视频数据光学无线广播传输,每个用户的接收带宽为 2Mbit/s,传输距离为2m。     

High-sensitivity and no-crosstalk pixel technology for embeddedCMOS image sensor

A high-photosensitivity and no-crosstalk pixel technology has been developed for an embedded active-pixel CMOS image sensor, by using a 0.35-μm CMOS logic process. To increase the photosensitivity, we developed a deep p-well photodiode and an antireflective film, consisting of Si₃N₄ film, for the photodiode surface. To eliminate the high voltage required for the reset transistor in the pixel, we used a depletion-type transistor as the reset transistor. The reset transistor also operates as an overflow control gate, which enables antiblooming overflow when excess charge is generated in the photodiode by high-illumination conditions. To suppress pixel crosstalk caused by obliquely incident light, a double-metal photoshield was used, while crosstalk caused by electron diffusion in the substrate was suppressed by using the deep p-well photodiode. A 1/3-in 330-k-pixel active-pixel CMOS image sensor was fabricated using this technology. A sensitivity improvement of 110% for 550-nm incident light was obtained by using the deep p-well photodiode, while an improvement of 24% was obtained by using the antireflective film. The pixel crosstalk was suppressed to less than 1% throughout the range of visible light     

Elimination or minimisation of optoelectronic crosstalk betweenphotodiodes and electronic devices in OEIC on Si

The optoelectronic crosstalk between photodiodes and electronic devices is observed and investigated in OEICs based on silicon. Results show that the phenomenon is closely related to the diffusion of minority carriers, generated by photon absorption. The crosstalk can be eliminated or minimised by either placing the electronic devices far from the photodiode, or by enclosing them with a reverse-biased guard ring diode     

Optical Data Link Employing Organic Light-Emitting Diodes and Organic Photodiodes as Optoelectronic Components

An optical interconnect solely using organic optoelectronic components is presented. The data link is based on an organic light-emitting diode as the transmitter and an organic photodiode as the receiver. Light is transmitted via a polymer optical fiber coupled to the active components. A digitized audio signal based on the Sony/Philips Digital Interface Format standard at a signal bit rate of 2.8224 Mbit/s (44.1-kHz sampling frequency) is successfully transmitted.     

室内可见光通信APD 探测电路的设计与实现

室内可见光无线通信技术是随着白光LED 照明技术的发展而兴起的无线光通信技术。在分析目前的可见光通信技术基础上,针对室内可见光通信系统的应用需求,设计了雪崩光电二极管(APD)探测电路组件。首先阐述了APD 探测电路的工作原理,其次详细设计并分析了系统各组成部分的电路结构及其功能,最后对所设计的用于室内可见光通信接收子系统的探测组件进行了相关实验测试。实验结果表明:设计有效可行,APD 探测电路具有增益高、带宽宽、温控可靠、稳定性好等优点,对室内可见光通信系统有很好的应用价值,为室内可见光通信系统进一步研究提供依据。     

A miniature hybrid reflection type optical sensor for measurementof hemoglobin content and oxygen saturation of whole blood

A reflection-type hybrid optical sensor was designed for continuous measurement of both hemoglobin content ([Hb]) and oxygen saturation (OS) of whole blood. The sensor was based on a theoretical model using the photon diffusion theory. The prototype sensor consists of a light emitting diode (LED) and photodiode chips mounted on a single substrate and cased in a TO-5 can with its surface covered with clear epoxy resin. The effect of hematocrit variation was eliminated. It was test in goat, calf, and human whole blood over hematocrit range of 20-45%. The modified ratio method reduced the effect of hematocrit variation of hemoglobin OS measurement with improvement in standard deviation of errors from about 7.0 to 2.0%. The standard errors in the estimation of hemoglobin content ranged from 1.5 to 0.5 gm%. The oxygen contents of whole blood derived from the prototype sensor correlated well (r=0.997) with those analyzed using a hemoximeter. The prototype sensors have been used for continuous measurement of oxygen delivery to, and oxygen consumption by, peripheral tissues in artificial heart animals for a duration of 40 days, demonstrating satisfactory performance     

Development of a dual function sensor system for measuring pressureand temperature at the tip of a single optical fiber

A dual function sensor system has been developed for measuring pressure and temperature at the tip of a single optical fiber. The sensor contains three parts: a filter band-edge shift temperature sensor, a short-wavelength-reflecting dichroic filter, and a diaphragm-based spectral modulation pressure sensor. The sensor system uses a separate and distinct light-emitting diode (LED) for interrogating each sensor, three 100/140 mm step-index fused couplers for managing light, and separate paired photodiode assemblies for analyzing the return light signal from each sensor. In bench tests, each sensor performed to specification and there was no crosstalk between sensors. This sensor design has potential catheter applications where catheter size must be kept to an absolute minimum     

Silicon photodiode as a photosensitive capacitance

In this paper the influence of light on the junction capacitance of a silicon photodiode is discussed. The analysis carried out deals with an open-circuited and reverse-biased photodiode. In this analysis the dependence of the photocurrent sensitivity and the differential conductance on an illumination and an applied voltage is included. The dependence of the open-circuit voltage on an illumination, with the d.c. performance of a silicon diode at low currents taken into consideration, is also derived. The presented analysis shows that the specific performance of a photodiode gives possibilities to use this element in detecting very low illuminations.     

Characterization of an Integrated Fluorescence-Detection Hybrid Device With Photodiode and Organic Light-Emitting Diode

A new integrated fluorescence-detection hybrid device with a photodiode and an organic light-emitting diode (OLED), and its characteristics are presented. To detect the fluorescent signal using OLED as a light source, a finger-type photodiode with low parasitic resistance was designed, which utilizes the side depletion region in the$hboxp^+hboxn$junction. In addition, OLED was designed to have the peak intensity at an excitation wavelength from rhodamine 6G. The integrated fluorescence-detection hybrid device fabricated had a background signal of 153 nA and a limit of detection of 1$muhboxM$, and was applied in the competitive assay.