光电式传感器中英文对照外文翻译文献
光电式传感器论文中英文资料对照外文翻译
附件1：外文资料翻译译文光电式传感器的应用与发展摘要目前,光电式传感器的应用范围越来越广,这大大促进了光电式传感器的发展。
光电式传感器结构简单而且形式多样。
它具有精度高，响应速度快，非接触等优点。
在本文中，我们分析了光电式传感器的工作原理,介绍了光电式传感器的分类,然后重点介绍了光电式传感器的应用和使用原理,分析了光电式传感器的现状和未来的发展趋势。
关键词光电式传感器，光电式传感器的应用，光电式传感器的发展1 引言光电式传感器是一种将光学元件和电子元件作为检测部分的传感器。
光电检测技术具有精度高，响应速度快，非接触式等优点。
该传感器结构简单，形式灵活多样。
因此，光电式传感器被广泛运用于控制和测试领域。
它可用于检测由于光量变化导致的非电量变化，如光强，辐射温度，气体成分等等。
它也可以通过光的传输，阻隔，反射，干扰来测量各种物理量，如物体的大小，位移，速度，温度等。
所以它是一个具有广泛应用前景的至关重要的灵敏器件。
当使用光电式传感器时，光电式传感器不直接与被测物体接触，光束质量几乎为零，在测量过程中不存在摩擦力，且在被测物体上几乎没有任何压力。
因此，光电传感器在很多应用方面都比其他传感器具有明显的优势。
然而，它的缺点是在某些应用场合中光学器件和电子设备是比较昂贵的，而且在测量过程中对环境条件的要求较高。
近年来，新型光电子器件的不断涌现为光电式传感器的进一步应用开创了新的一页尤其是CCD图像传感器的出现。
2 光电传感器的原理光电传感器是以光电器件作为转换元件的传感器。
该光电传感器的原理是把被测量的变化转换成光信号的变化，然后借助光电元件进一步将光信号转换成电信号的光电组件。
光电传感器一般由光源、光学通路和光电元件三部分组成。
光电传感器的工作过程如图1所示。
图1 光电式传感器的工作过程光电器件的作用是将光信号转换成基于光电效应的电信号。
光电效应是一种物理现象，光照射到某些物质，并导致物体电性质发生重大改变。
光电传感器英文和译文
Progress in Materials ScienceV olume 46, Issues 3–4, 2001, Pages 461–504The selection of sensorsJ Shieh,J.E Huber,N.A Fleck, ,M.F AshbyDepartment of Engineering, Cambridge University, Trumpington Street, Cambridge CB2 1PZ, UK Available online 14 March 2001./10.1016/S0079-6425(00)00011-6, How to Cite or Link Using DOI Permissions & ReprintsAbstractA systematic method is developed to select the most appropriate sensor for a particular application.A wide range of candidate sensors exist, and many are based on coupled electrical and mechanical phenomena, such as the piezoelectric, magnetostrictive and the pyro-electric effects. Performance charts for sensors are constructed from suppliers data for commercially available devices. The selection of an appropriate sensor is based on matching the operating characteristics of sensors to the requirements of an application. The final selection is aided by additional considerations such as cost, and impedance matching. Case studies illustrate the selection procedure.KeywordsSensors;Selection;Sensing range;Sensing resolution;Sensing frequency1. IntroductionThe Oxford English Dictionary defines a sensor as “a device which detects or measures some condition or property, and records, indicates, or otherwise responds to the information received”. Thus, sensors have the function of converting a stimulus into a measured signal. The stimulus can be mechanical, thermal, electromagnetic, acoustic, or chemical in origin (and so on), while the measured signal is typically electrical in nature, although pneumatic, hydraulic and optical signals may be employed. Sensors are an essential component in the operation of engineering devices, and are based upon a very wide range of underlying physical principles of operation.Given the large number of sensors on the market, the selection of a suitable sensor for a newapplication is a daunting task for the Design Engineer: the purpose of this article is to provide a straightforward selection procedure.The study extends that of Huber et al. [1] for the complementary problem of actuator selection. It will become apparent that a much wider choice of sensor than actuator is available: the underlying reason appears to be that power-matching is required for an efficient actuator, whereas for sensors the achievable high stability and gain of modern-day electronics obviates a need to convert efficiently the power of a stimulus into the power of an electrical signal. The classes of sensor studied here are detailed in the Appendices. 2. Sensor performance chartsIn this section, sensor performance data are presented in the form of 2D charts with performance indices of the sensor as axes. The data are based on sensing systems which are currently available on the market. Therefore, the limits shown on each chart are practical limits for readily available systems, rather than theoretical performance limits for each technology. Issues such as cost, practicality (such as impedance matching) and reliability also need to be considered when making a final selection from a list of candidate sensors.Before displaying the charts we need to introduce some definitions of sensor characteristics; these are summarised in Table 1.1 Most of these characteristics are quoted in manufacturers' data sheets. However, information on the reliability and robustness of a sensor are rarely given in a quantitative manner.Table 1. Summary of the main sensor characteristicsRange maximum minus minimum value of the measured stimulusResolution smallest measurable increment in measured stimulusSensing frequency maximum frequency of the stimulus which can be detectedAccuracy error of measurement, in% full scale deflectionSize leading dimension or mass of sensorOpt environment operating temperature and environmental conditionsReliability service life in hours or number of cycles of operationDrift long term stability (deviation of measurement over a time period)Cost purchase cost of the sensor ($ in year 2000)Full-size tableIn the following, we shall present selection charts using a sub-set of sensor characteristics: range, resolution and frequency limits. Further, we shall limit our attention to sensors which can detect displacement, acceleration, force, and temperature.2 Each performance chart maps the domain of existence of practical sensors. By adding to the chart the required characteristics for a particular application, a subset of potential sensors can be identified. The optimal sensor is obtained by making use of several charts and by considering additional tabular information such as cost. The utility of the approach is demonstrated in Section 3, by a series of case studies.2.1. Displacement sensorsConsider first the performance charts for displacement sensors, with axes of resolution δversus range R, and sensing frequency f versus range R, as shown in Fig. 1 and Fig. 2, respectively.Fig. 1. Resolution versus sensing range for displacement sensors. View thumbnail imagesFig. 2. Sensing frequency versus sensing range for displacement sensors.View thumbnail images2.1.1. Resolution —sensing range chart (Fig. 1)The performance regime of resolution δversus range R for each class of sensor is marked by a closed domain with boundaries given by heavy lines (see Fig. 1). The upper limit of operation is met when the coarsest achievable resolution equals the operating range δ=R. Sensors of largest sensing range lie towards the right of the figure, while sensors of finest resolution lie towards the bottom. It is striking that the range of displacement sensor spans 13 orders of magnitude in both range and resolution, with a large number of competing technologies available. On these logarithmic axes, lines of slope +1 link classes of sensors with the same number of distinctmeasurable positions, . Sensors close to the single position line δ=R are suitable as simple proximity (on/off) switches, or where few discrete positions are required. Proximity sensors are marked by a single thick band in Fig. 1: more detailed information on the sensing range and maximum switching frequency of proximity switches are summarised in Table 2. Sensors located towards the lower right of Fig. 1 allow for continuous displacement measurement, with high information content. Displacement sensors other than the proximity switches are able to provide a continuous output response that is proportional to the target's position within the sensing range.Fig. 1 shows that the majority of sensors have a resolving power of 103–106 positions; this corresponds to approximately 10–20 bits for sensors with a digital output.Table 2. Specification of proximity switchesProximity switch typeMaximum switching distance (m) Maximum switchingfrequency (Hz) Inductive6×10−4–1×10−1 5–5000 Capacitive1×10−3–6×10−2 1–200 Magnetic 3×10−3–8.5×10−2 400–5000 Pneumatic cylinder sensors (magnetic) Piston diameter 8×10−3–3.2×10−1300–5000 Ultrasonic1.2×10−1–5.2 1–50 Photoelectric 3×10−3–300 20–20,000Full-size tableIt is clear from Fig. 1 that the sensing range of displacement sensors cluster in the region 10−5–101 m. To the left of this cluster, the displacement sensors of AFM and STM, which operate on the principles of atomic forces and current tunnelling, have z-axis-sensing ranges on the order of microns or less. For sensing tasks of 10 m or above, sensors based on the non-contacting technologies of linear encoding, ultrasonics and photoelectrics become viable. Optical linear encoders adopting interferometric techniques can achieve a much higher resolution than conventional encoders; however, their sensing range is limited by the lithographed carrier (scale).A switch in technology accounts for the jump in resolution of optical linear encoders around the sensing range of 0.7 m in Fig. 1.Note that “radar ”, which is capable of locating objects at distances of several thousand kilometres,3 is not included in Fig. 1. Radar systems operate by transmitting high-frequency radio waves and utilise the echo and Doppler shift principles to determine the position and speed of the target. Generally speaking, as the required sensing range increases, sensors based on non-contact techniques become the most practicable choice due to their flexibility, fast sensing speed and small physical size in relation to the length scale detected. Fig. 1 shows that sensors based on optical techniques, such as fibre-optic, photoelectric and laser triangulation, cover the widest span in sensing range with reasonably high resolution.For displacement sensors, the sensing range is governed by factors such as technology limitation, probe (or sensing face) size and the material properties of the target. For example, the sensing distance of ultrasonic sensors is inversely proportional to the operating frequency; therefore, a maximum sensing range cut-off exists at about R=50 m. Eddy current sensors of larger sensing face are able to produce longer, wider and stronger electromagnetic fields, which increase their sensing range. Resolution is usually controlled by the speed, sensitivity and accuracy of the measuring circuits or feedback loops; noise level and thermal drift impose significant influences also. Sensors adopting more advanced materials and manufacturing processes can achieve higher resolution; for example, high-quality resistive film potentiometers have a resolution of better than 1 μm over a range of 1 m (i.e. 106 positions) whereas typical coil potentiometers achieve only 103 positions.2.1.2. Sensing frequency — sensing range chart (Fig. 2)When a displacement sensor is used to monitor an oscillating body, a consideration of sensing frequency becomes relevant. Fig. 2 displays the upper limit of sensing frequency and the sensorrange for each class of displacement sensor. It is assumed that the smallest possible sensing range of a displacement sensor equals its resolution; therefore in Fig. 2, the left-hand side boundary of each sensor class corresponds to its finest resolution.4 However, sensors close to this boundary are only suitable as simple switches, or where few discrete positions are to be measured.Lines of slope −1 in Fig. 2 link classes of sensors with the same sensing speed, fR. For contact sensors such as the LVDT and linear potentiometer, the sensing speed is limited by the inertia of moving parts. In contrast, many non-contact sensors utilise mechanical or electromagnetic waves and operate by adopting the time-of-flight approach; therefore, their maximum sensing speed is limited by the associated wave speed. For example, the maximum sensing speed of magnetostrictive sensors is limited by the speed of a strain pulse travelling in the waveguide alloy, which is about 2.8×103 m s−1.The sensing frequency of displacement sensors is commonly dependent on the noise levels exhibited by the measuring electronic circuits. Additionally, some physical and mechanical limits can also impose constraints. For example, the dynamic response of a strain gauge is limited by the wave speed in the substrate. For sensors with moving mass (for example, linear encoder, LVDT and linear potentiometer), the effects of inertial loading must be considered in cyclic operation. For optical linear encoders the sensing frequency increases with range on the left-hand side of the performance chart, according to the following argument. The resolution becomes finer (i.e. δdecreases in an approximately linear manner) with a reduced scan speed V of the recording head. Since the sensor frequency f is proportional to the scan speed V, we deduce that f increases linearly with δ, and therefore f is linear in the minimum range of the device.2.2. Linear velocity sensorsAlthough velocity and acceleration are the first and second derivatives of displacement with respect to time, velocity and acceleration measurements are not usually achieved by time differentiation of a displacement signal due to the presence of noise in the signal. The converse does not hold: some accelerometers, especially navigation-grade servo accelerometers, have sufficiently high stability and low drift that it is possible to integrate their signals to obtain accurate velocity and displacement information.The most common types of velocity sensor of contacting type are electromagnetic, piezoelectric and cable extension-based. Electromagnetic velocity sensors use the principle of magnetic induction, with a permanent magnet and a fixed geometry coil, such that the induced (output) voltage is directly proportional to the magnet's velocity relative to the coil. Piezo-velocity transducers (PVTs) are piezoelectric accelerometers with an internal integration circuit which produces a velocity signal. Cable extension-based transducers use a multi-turn potentiometer (or an incremental/absolute encoder) and a tachometer to measure the rotary position and rotating speed of a drum that has a cable wound onto it. Since the drum radius is known, the velocity and displacement of the cable head can be determined.5Optical and microwave velocity sensors are non-contacting, and utilise the optical-grating or Doppler frequency shift principle to calculate the velocity of the moving target. Typical specifications for each class of linear velocity sensor are listed in Table 3.Table 3. Specification of linear velocity sensorsSensor class Maximum sensingrange (m/s)Resolution (number ofpositions)Maximum operatingfrequency (Hz)Magnetic induction 25–360 5×104–5×105 100–1500Sensor class Maximum sensingrange (m/s)Resolution (number ofpositions)Maximum operatingfrequency (Hz)PVT 0.25–1.3 1×105–5×105 ∼7000Cable-extension 0.7–15 1×105–1×106 1–100Optical andmicrowave13–165 ∼1×105 > 10,000目录1. 简介 (8)2. 传感器性能图表 (9)2.1．位移传感器 (10)2.1.1．分辨率- 感应范围图（图1） (11)2.1.2.检测频率–检测范围图（图2） (12)2.2．线性速度传感器 (12)问题3-4，2001年第46卷，页461-504传感器的选择J Shieh,J.E Huber,N.A FleckM.F Ashby剑桥大学工程系，英国剑桥CB2的1PZ，，Trumpington街________________________________________摘要对于一个特定的应用系统来说要选择最为合适的传感器。
光学传感器毕业论文中英文文献及翻译
英文文献及中文翻译一种精确测量倾斜角度的光学传感器摘要本文主要介绍了一种新型光学传感器，它可以同时准确地测量倾斜角或两轴倾斜角度。
这种传感器是基于激光干涉原理，因此具有很高的精度。
设计制作了一个传感器的模型来论证这个新的方法，这是一个光电传感器,传感器中没有移动的部分。
由正交于铅垂面的流动水平面提供参考面。
传感器和绝对水平面之间的角度随着被测量的物体倾斜而改变，这些变化反映在条纹图案的中心位置的转移方式。
不同的干涉条纹的中心位置随倾斜角的变化而改变。
干涉条纹图案进行记录和处理，转化为两轴、水平和垂直倾斜角度。
当使用1024*1024像素的传感器时，测量范围为700弧秒，其精度可高达+/ - 1弧秒。
关键词：倾斜角度传感器，倾斜仪，激光干涉I 介绍市场上目前有几种类型的商业倾斜角度测量传感器。
有些是角度传感器，有些是倾斜仪，它们的工作原理不同。
电解液体、电容和钟摆是现在大多数倾斜角度传感器和倾斜仪的三个主要工作原理。
在这里，我们提出了一种新的光学方法，建立了一个用激光、光学元件和图像传感器的光电传感器，它可以同时做精确的倾斜角度测量，不需要进行机械的移动，其工作原理是基于光学干涉，相干激光作为光源。
光线通过一个装满液态油的玻璃油盒。
由正交于铅垂面的流动水平面提供参考面。
当激光束穿过油箱有两束光线反射回来，一束是液体的表面产生的，另一束是容器玻璃产生的，干涉条纹就是由这两条光线形成的，条纹图案将随着倾斜角度的变化产生相应的变化，条纹图案采集和处理后将反映倾斜角度信息，光学工作原理使它不受磁场的影响。
该传感器可以同时测量两轴倾角。
流动的水平面确保了参考面是一个绝对的水平面。
高灵敏度光学干涉测量原理，保证了较高的精度。
II 原理图1说明了工作原理示意图，O点是光线扩大镜头的焦点，O点可以看作是点光源，它发出球面波。
由于地球重力的影响，液体油面始终保持水平，因此用油面作为参考平面。
该容器是玻璃材料的。
当传感器被放在目标表面时，其底部表面将连同目标对象一起倾斜。
传感器技术论文中英文对照资料外文翻译文献
传感器技术论文中英文对照资料外文翻译文献Development of New Sensor TechnologiesSensors are devices that can convert physical。
chemical。
logical quantities。
etc。
into electrical signals。
The output signals can take different forms。
such as voltage。
current。
frequency。
pulse。
etc。
and can meet the requirements of n n。
processing。
recording。
display。
and control。
They are indispensable components in automatic n systems and automatic control systems。
If computers are compared to brains。
then sensors are like the five senses。
Sensors can correctly sense the measured quantity and convert it into a corresponding output。
playing a decisive role in the quality of the system。
The higher the degree of n。
the higher the requirements for sensors。
In today's n age。
the n industry includes three parts: sensing technology。
n technology。
and computer technology。
传感器外文翻译文献
传感器外文翻译文献(文档含中英文对照即英文原文和中文翻译)译文：传感器的基础知识传感器是一种将能量转化为光的、机械的或者更为普遍的电信号，这种能量转换发生的过程称之为换能作用。
按照能量转换的复杂程度和控制方式，传感器被分为不同的等级，用来测量位移的电阻式传感器被分类为电阻式位移传感器，其他的分类诸如压力波纹管、压力膜和压力阀等。
1、传感器元件大多数的传感器是由感应元件，转换元件、控制元件、当然也有例外，例如：震动膜、.波纹管、应力管和应力环、低音管和悬臂都是敏感元件。
对物理量作出反应，将物理的压力和力转换为位移，这些转换量可以被用作电参数，如电压、电阻、电容或者感应系数。
机械式和电子式元件合并形成机电式传感设备或传感器。
相似量的结合可以作为能量输入例如：热的、光的、磁的、化学的相互结合产生的热电式、光电式、电磁式和电化学式传感器。
2、传感器灵敏度通过校正测量系统获得的被测物理量和传感器输出信号的关系叫做传感器灵敏度K1=输出信号增量∕被测量的增量，实际上，传感器的灵敏度是已知的通过测量输出信号，输入量由下式决定，输入量=输出信号的增量∕k1。
3、理想传感器的性能特点：a)高保真性：传感器的输出波形式对被测量的真实展现，并且失真很小。
b)被测量干扰最小，任何情况下传感器的精度不能改变。
c)尺寸：必须将传感器正确的放在所需要的场所。
d)被测量和传感器信号之间要有线性关系。
e)传感器对外部变换由很小的灵敏度,例如：压力传感器常常受到外部震动和环境温度的影响f)传感器的固有频率应能够避开被测量的频率和谐波。
4、电传感器电传感器由很多理想特性，它们不仅实现远程测量和显示，还能提供高灵敏度。
电传感器可分为如下两大类。
这些传感器依靠外界电压刺激来工作。
A、变参数型包括：ⅰ）电阻式ⅱ）电容式ⅲ）感应式ⅳ）自感应式ⅴ）互感应式B、自激型包括:ⅰ)电磁式；ⅱ）热电式ⅲ）光栅式；ⅳ）压电式。
这些传感器都是自己产生输出电压来反映被测量的输入并且这些过程是可逆的;例如，一般的电子传感器通常能产生出输出电压来反映晶体材料的性能，.然而，如果在材料上加一个自变电压，传感器可以通过变形或与变电压同频率的振动来体现可逆效应。
传感器的基础知识中英文对照外文翻译文献
中英文对照外翻译Basic knowledge of transducersA transducer is a device which converts the quantity being measured into an optical, mechanical, or-more commonly-electrical signal. The energy-conversion process that takes place is referred to as transduction.Transducers are classified according to the transduction principle involved and the form of the measured. Thus a resistance transducer for measuring displacement is classified as a resistance displacement transducer. Other classification examples are pressure bellows, force diaphragm, pressure flapper-nozzle, and so on.1、Transducer ElementsAlthough there are exception ,most transducers consist of a sensing element and a conversion or control element. For example, diaphragms,bellows,strain tubes and rings, bourdon tubes, and cantilevers are sensing elements which respond to changes in pressure or force and convert these physical quantities into a displacement. This displacement may then be used to change an electrical parameter such as voltage, resistance, capacitance, or inductance. Such combination of mechanical and electrical elements form electromechanical transducing devices or transducers. Similar combination can be made for other energy input such as thermal. Photo, magnetic and chemical,giving thermoelectric, photoelectric,electromaanetic, and electrochemical transducers respectively.2、Transducer SensitivityThe relationship between the measured and the transducer output signal is usually obtained by calibration tests and is referred to as the transducer sensitivity K1= output-signal increment / measured increment . In practice, the transducer sensitivity is usually known, and, by measuring the output signal, the input quantity is determined from input= output-signal increment / K1.3、Characteristics of an Ideal TransducerThe high transducer should exhibit the following characteristicsa) high fidelity-the transducer output waveform shape be a faithful reproduction of the measured; there should be minimum distortion.b) There should be minimum interference with the quantity being measured; the presence of the transducer should not alter the measured in any way.c) Size. The transducer must be capable of being placed exactly where it is needed.d) There should be a linear relationship between the measured and the transducer signal.e) The transducer should have minimum sensitivity to external effects, pressure transducers,for example,are often subjected to external effects such vibration and temperature.f) The natural frequency of the transducer should be well separated from the frequency and harmonics of the measurand.4、Electrical TransducersElectrical transducers exhibit many of the ideal characteristics. In addition they offer high sensitivity as well as promoting the possible of remote indication or mesdurement. Electrical transducers can be divided into two distinct groups:a) variable-control-parameter types,which include:i)resistanceii) capacitanceiii) inductanceiv) mutual-inductance typesThese transducers all rely on external excitation voltage for their operation.b) self-generating types,which includei) electromagneticii)thermoelectriciii)photoemissiveiv)piezo-electric typesThese all themselves produce an output voltage in response to the measurand input and their effects are reversible. For example, a piezo-electric transducer normally produces an output voltage in response to the deformation of a crystalline material; however, if an alternating voltage is applied across the material, the transducer exhibits the reversible effect by deforming or vibrating at the frequency of the alternating voltage.5、Resistance TransducersResistance transducers may be divided into two groups, as follows:i) Those which experience a large resistance change, measured by using potential-divider methods. Potentiometers are in this group.ii)Those which experience a small resistance change, measured by bridge-circuit methods. Examples of this group include strain gauges and resistance thermometers.5.1 PotentiometersA linear wire-wound potentiometer consists of a number of turns resistance wire wound around a non-conducting former, together with a wiping contact which travels over the barwires. The construction principles are shown in figure which indicate that the wiperdisplacement can be rotary, translational, or a combination of both to give a helical-type motion. The excitation voltage may be either a.c. or d.c. and the output voltage is proportional to the input motion, provided the measuring device has a resistance which is much greater than the potentiometer resistance.Such potentiometers suffer from the linked problem of resolution and electrical noise. Resolution is defined as the smallest detectable change in input and is dependent on thecross-sectional area of the windings and the area of the sliding contact. The output voltage is thus a serials of steps as the contact moves from one wire to next.Electrical noise may be generated by variation in contact resistance, by mechanical wear due to contact friction, and by contact vibration transmitted from the sensing element. In addition, the motion being measured may experience significant mechanical loading by the inertia and friction of the moving parts of the potentiometer. The wear on the contacting surface limits the life of a potentiometer to a finite number of full strokes or rotations usually referred to in the manufacture’s specification as the ‘number of cycles of life expectancy’, a typical value being 20*1000000 cycles.The output voltage V0 of the unload potentiometer circuit is determined as follows. Let resistance R1= xi/xt *Rt where xi = input displacement, xt= maximum possible displacement, Rt total resistance of the potentiometer. Then output voltage V0= V*R1/(R1+( Rt-R1))=V*R1/Rt=V*xi/xt*Rt/Rt=V*xi/xt. This shows that there is a straight-line relationship between output voltage and input displacement for the unloaded potentiometer.It would seen that high sensitivity could be achieved simply by increasing the excitation voltage V. however, the maximum value of V is determined by the maximum power dissipation P of the fine wires of the potentiometer winding and is given by V=(PRt)1/2 .5.2 Resistance Strain GaugesResistance strain gauges are transducers which exhibit a change in electrical resistance in response to mechanical strain. They may be of the bonded or unbonded variety .a) bonded strain gaugesUsing an adhesive, these gauges are bonded, or cemented, directly on to the surface of the body or structure which is being examined.Examples of bonded gauges arei) fine wire gauges cemented to paper backingii) photo-etched grids of conducting foil on an epoxy-resin backingiii)a single semiconductor filament mounted on an epoxy-resin backing with copper or nickel leads.Resistance gauges can be made up as single elements to measuring strain in one direction only,or a combination of elements such as rosettes will permit simultaneous measurements in more than one direction.b) unbonded strain gaugesA typical unbonded-strain-gauge arrangement shows fine resistance wires stretched around supports in such a way that the deflection of the cantilever spring system changes the tension in the wires and thus alters the resistance of wire. Such an arrangement may be found in commercially available force, load, or pressure transducers.5.3 Resistance Temperature TransducersThe materials for these can be divided into two main groups:a) metals such as platinum, copper, tungsten, and nickel which exhibit and increase in resistance as the temperature rises; they have a positive temperature coefficient of resistance.b) semiconductors, such as thermistors which use oxides of manganese, cobalt, chromium, or nickel. These exhibit large non-linear resistance changes with temperature variation and normally have a negative temperature coefficient of resistance.a) metal resistance temperature transducersThese depend, for many practical purpose and within a narrow temperature range, upon the relationship R1=R0*[1+a*(b1-b2)] where a coefficient of resistance in ℃-1,and R0 resistance in ohms at the reference temperature b0=0℃ at the reference temperature range ℃.The international practical temperature scale is based on the platinum resistance thermometer, which covers the temperature range -259.35℃ to 630.5℃.b) thermistor resistance temperature transducersThermistors are temperature-sensitive resistors which exhibit large non-liner resistance changes with temperature variation. In general, they have a negative temperature coefficient. For small temperature increments the variation in resistance is reasonably linear; but, if large temperature changes are experienced, special linearizing techniques are used in the measuring circuits to produce a linear relationship of resistance against temperature.Thermistors are normally made in the form of semiconductor discs enclosed in glass vitreous enamel. Since they can be made as small as 1mm,quite rapid response times are possible.5.4 Photoconductive CellsThe photoconductive cell , uses a light-sensitive semiconductor material. The resistance between the metal electrodes decrease as the intensity of the light striking the semiconductor increases. Common semiconductor materials used for photo-conductive cells are cadmium sulphide, lead sulphide, and copper-doped germanium.The useful range of frequencies is determined by material used. Cadmium sulphide is mainly suitable for visible light, whereas lead sulphide has its peak response in the infra-red regionand is, therefore , most suitable for flame-failure detection and temperature measurement. 5.5 Photoemissive CellsWhen light strikes the cathode of the photoemissive cell are given sufficient energy to arrive the cathode. The positive anode attracts these electrons, producing a current which flows through resistor R and resulting in an output voltage V.Photoelectrically generated voltage V=Ip.RlWhere Ip=photoelectric current(A),and photoelectric current Ip=Kt.BWhere Kt=sensitivity (A/im),and B=illumination input (lumen)Although the output voltage does give a good indication of the magnitude of illumination, the cells are more often used for counting or control purpose, where the light striking the cathode can be interrupted.6、Capacitive TransducersThe capacitance can thus made to vary by changing either the relative permittivity, the effective area, or the distance separating the plates. The characteristic curves indicate that variations of area and relative permittivity give a linear relationship only over a small range of spacings. Thus the sensitivity is high for small values of d. Unlike the potentionmeter, the variable-distance capacitive transducer has an infinite resolution making it most suitable for measuring small increments of displacement or quantities which may be changed to produce a displacement.7、Inductive TransducersThe inductance can thus be made to vary by changing the reluctance of the inductive circuit. Measuring techniques used with capacitive and inductive transducers:a)A.C. excited bridges using differential capacitors inductors.b)A.C. potentiometer circuits for dynamic measurements.c) D.C. circuits to give a voltage proportional to velocity for a capacitor.d) Frequency-modulation methods, where the change of C or L varies the frequency of an oscillation circuit.Important features of capacitive and inductive transducers are as follows:i)resolution infiniteii) accuracy+- 0.1% of full scale is quotediii)displacement ranges 25*10-6 m to 10-3miv) rise time less than 50us possibleTypical measurands are displacement, pressure, vibration, sound, and liquid level.8、Linear Variable-differential Ttransformer9、Piezo-electric Transducers10、Electromagnetic Transducers11、Thermoelectric Transducers12、Photoelectric Cells13、Mechanical Transducers and Sensing Elements传感器的基础知识传感器是一种把被测量转换为光的、机械的或者更平常的电信号的装置。
光电传感器(中英文对照版)
Photoelectric sensorKey word: photoelectric effect photoelectric element photoelectric sensor classification sensor application characteristics .Abstract: in the rapid development of science and technology in the modern society, mankind has into the rapidly changing information era, people in daily life, the production process, rely mainly on the detection of information technology by acquiring, screening and transmission, to achieve the brake control, automatic adjustment, at present our country has put detection techniques listed in one of the priority to the development of science and technology. Because of microelectronics technology, photoelectric semiconductor technology, optical fiber technology and grating technical development makes the application of the photoelectric sensor is growing. The sensor has simple structure, non-contact, high reliability, high precision, measurable parameters and quick response and more simple structure, form etc, and flexible in automatic detection technology, it has been widely applied in photoelectric effect as the theoretical basis, the device by photoelectric material composition. Text:First, theoretical foundation - photoelectric effectPhotoelectric effect generally have the photoelectric effect, optical effect, light born volts effect.The light shines in photoelectric material, according to the electronic absorption material surface energy, if absorbed energy large enough electronic electronic will overcome bound from material surface and enter the outside space, which changes photoelectron materials, this kind of phenomenon become the conductivity of the photoelectric effectAccording to Einstein's photoelectron effect, photon is moving particles, each photon energy for hv (v for light frequency, h for Planck's constant, h = 6.63 * 10-34 J/HZ), thus different frequency of photons have different energy, light, the higher the frequency, the photon energy is bigger. Assuming all the energy photons to photons, electronic energy will increase, increased energy part of the fetter, positive ions used to overcome another part of converted into electronic energy. According to the law of conservation of energy:Type, m for electronic quality, v for electronic escaping the velocity, A microelectronics the work done.From the type that will make the optoelectronic cathode surface escape the necessary conditions are h > A. Due to the different materials have different escaping, so reactive to each kind of cathode materials, incident light has a certain frequency is restricted, when the frequency of incident light under this frequency limit, no matter how the light intensity, won't produce photoelectron launch, this frequency limit A -h m 212νν=called "red limit". The corresponding wavelength for type, c for the speed of light, A reactive for escaping.When is the sun, its electronic energy, absorb the resistivity reduce conductive phenomenon called optical effects. It belongs to the photoelectric effect within. When light is, if in semiconductor electronic energy big with semiconductor of forbidden band width, the electronic energy from the valence band jump into the conduction band, form, and at the same time, the valence band electronic left the corresponding cavities. Electronics, cavitation remained in semiconductor, and participate in electric conductive outside formed under the current role.In addition to metal outer, most insulators and semiconductor have photoelectric effect, particularly remarkable, semiconductor optical effect according to the optoelectronics manufacturing incident light inherent frequency, when light resistance in light, its conductivity increases, resistance drops. The light intensity is strong, its value, if the smaller, its resistance to stop light back to the original value. Semiconductor produced by light illuminate the phenomenon is called light emf, born volts effect on the effect of photoelectric devices have made si-based ones, photoelectric diode, control thyristor and optical couplers, etc.Second, optoelectronic components and characteristicsAccording to the outside optoelectronics manufacturing optoelectronic devices have photoelectron, inflatable phototubes and photoelectric times once tube.1. Phototubes phototubes are various and typical products are vacuum phototubes and inflatable phototubes, light its appearance and structure as shown in figure 1 shows, made of cylindrical metal half cathodic K and is located in the wires cathodic axis of anode in A package of smoke into the vacuum, when incident light within glass shell in the cathode, illuminate A single photon took all of its energy transfer to the cathode materials A free electrons, so as to make the freedom electronic energy increase h. When electrons gain energy more than escape of cathode materials, it reactive A metal surface constraints can overcome escape, form electron emission. This kind of electronic called optoelectronics, optoelectronic escaping the metal surface for after initial kinetic energyPhototubes normal work, anode potential than the cathode, shown in figure 2. In one shot more than "red light frequency is premise, escape from the optoelectronic cathode surface by positive potential attracted the anode in photoelectric tube forming space, called the current stream. Then if light intensity increases, the number of photons bombarded the cathode multiplied, unit of time to launch photoelectron number are also increasing, photo-current greatens. In figure 2 shows circuit, current and resistance is the voltage drop across the only a function of light intensity relations, so as to achieve a photoelectric conversion. When the LTT optoelectronic cathode K, electronic escape from the cathode surface, and was the photoelectric anode is an electric current, power plants absorb deoxidization device in the load resistance - I, the voltagePhototubes photoelectric characteristics fig.03 shows, from the graph in flux knowable, not too big, photoelectric basic characteristics is a straight line.2. Photoelectric times had the sensitivity of vacuum tube due to low, so with people developed has magnified the photomultiplier tubes photo-current ability. Figure 4 is photomultiplier tube structure schematic drawing.图4光电倍增结构示意图From the graph can see photomultiplier tubes also have A cathode K and an anode A, and phototubes different is in its between anode and cathode set up several secondary emission electrodes, D1, D2 and D3... They called the first multiply electrode, the second multiply electrode,... Usually, double electrode for 10 ~ 15 levels. Photomultiplier tubes work between adjacent electrode, keeping a certain minimum, including the cathode potential potentials, each multiply electrode potential filtering increases, the anode potential supreme. When the incident light irradiation, cathodic K escape from the optoelectronic cathode multiplied by first accelerated, by high speed electrode D1 bombarded caused secondary electron emission, D1, an incident can generate multiple secondary electron photonics, D1 emit of secondary electron wasD1, D2 asked electric field acceleration, converged on D2 and again produce secondary electron emission... So gradually produce secondary electron emission, make electronic increased rapidly, these electronic finally arrived at the anode, form a larger anode current. If a n level, multiply electrodes at all levels for sigma, the multiplication of rate is the multiplication of photomultiplier tubes can be considered sigma n rate, therefore, photomultiplier tube has high sensitivity. In the output current is less than 1mA circumstances, it in a very wide photoelectric properties within the scope of the linear relationship with good. Photomultiplier tubes this characteristic, make it more for light measurement.3 and photoconductive resistance photoconductive resistance within the working principle is based on the photoelectric effect. In semiconductor photosensitive material ends of mount electrode lead, it contains transparent window sealed in the tube and shell element photoconductive resistance. Photoconductive resistance properties and parameters are:1) dark resistance photoconductive resistance at room temperature, total dark conditions stable resistance called dark resistance, at the current flow resistance is called dark current.2) light resistance photoconductive resistance at room temperature and certain lighting conditions stable resistance measured, right now is called light resistance of current flow resistance is called light current.4, volt-ampere characteristics of both ends photoconductive resistance added voltage and current flows through photoconductive resistance of the relationship between called volt-ampere characteristics shown, as shown in figure 5. From the graph, the approximate linear volt-ampere characteristics that use should be limited, but when the voltage ends photoconductive resistance, lest than shown dotted lines of power consumption area5, photoelectric characteristics photoconductive resistance between the poles, light when voltage fixed the relationship between with bright current photoelectric characteristics. Called Photoconductive resistance photoelectric characteristics is nonlinear, this is one of the major drawback of photoconductive resistance.6, spectral characteristics is not the same incident wavelength, the sensitivity of photoconductive resistance is different also. Incidence wavelength and photodetector the relationship between relative sensitivity called spectral characteristics. When used according to the wavelength range by metering, choose different material photoconductive resistance.7, response time by photoconductive resistance after photo-current need light, over a period of time (time) rise to reach its steady value. Similarly, in stop lightphoto-current also need, over a period of time (down time) to restore the its dark current, this is photoconductive resistance delay characteristics. Photoconductive resistance rise response time and falling response time about 10-1 ~ 10-3s, namely the frequency response is 10Hz ~ 1000Hz, visible photoconductive resistance cannot be used in demand quick response occasion, this is one of the main photoconductive resistance shortcomings.8 and temperature characteristic photoconductive resistance by temperature affects greatly, temperature rise, dark current increase, reduced sensitivity, which is another photoconductive resistance shortcomings.9, frequency characteristic frequency characteristics refers to an external voltage and incident light, strong must be photo-current I and incident light modulation frequency, the relationship between the f, photoelectric diode is the frequency characteristic of the photoelectric triode frequency characteristics, this is because of the photoelectrictriode shot "yankees there capacitance and carrier base-combed need time's sake. By using the principle of the photoelectric efficiency of optoelectronics manufacturing frequency characteristics of the worst, this is due to capture charge carriers and release charge need a certain time's sake.Three, photoelectric sensorsPhotoelectric sensor is through the light intensity changes into electrical signal changes to achieve control, its basic structure, it first figure 6 by measuring the change of change of converting the light signal, and then using photoelectric element further will light signals into electrical signal by photoelectric sensor general. Illuminant, optical path and optoelectronics. Three components of photoelectric detection method has high precision, fast response, non-contact wait for an advantage, but measurable parameters of simple structure, sensors, form flexible, therefore, photoelectric sensor in the test and control is widely used.By photoelectric sensor generally is composed of three parts, they are divided into: transmitter and receiver and detection circuit shown, as shown in figure 7, transmitter aimed at the target launch beam, the launch of the beam from semiconductor illuminant, general light emitting diode (LED), laser diode and infrared emission diode. Beam uninterrupted launch, or change the pulse width. Receivers have photoelectric diode, photoelectric triode, composed si-based ones. In front of the receiver, equipped with optical components such as lens and aperture, etc. In its back is detection circuit, it can filter out effective signal and the application of the signal. In addition, the structural components in photoelectric switch and launch plate and optical fiber, triangle reflex plate is solid structure launch device. It consists of small triangle cone of reflective materials, can make a beam accurately reflected back from plate, with practical significance. It can be in with the scope of optical axis 0 to 25, make beams change launch Angle from a root almost after launch line, passes reflection or from the rotating polygon.some basic returns.图7Photoelectric sensor is a kind of depend on is analyte and optoelectronics and light source, to achieve the relationship between the measured purpose, so the light source photoelectric sensor plays a very important role, photoelectric sensor power if a constant source, power is very important for design, the stability of the stability of power directly affect the accuracy of measurement, commonly used illuminant have the following kinds:1, leds is a change electric energy into light energy semiconductor devices. It has small volume, low power consumption, long life, fast response, the advantages of high mechanical strength, and can match and integrated circuits. Therefore, widely used in computer, instruments and automatic control equipment.2, silk light bulb that is one of the most commonly used illuminant, it has rich infrared light. If chosen optoelectronics, constitutes of infrared sensor sensitive colour filter can be added to the visible tungsten lamps, but only filter with its infrared does illuminant, such, which can effectively prevent other light interference.3, compared with ordinary light laser laser with energy concentration, directional good, frequency pure, coherence as well as good, is very ideal light sources.The light source, optical path and photoelectric device composition photoelectric sensor used in photoelectric detection, still must be equipped with appropriate measurement circuit. The photoelectric effect to the measurement circuit of photoelectric element of widerange caused changes needed to convert the voltage or current. Different photoelectric element, the measurement circuit required is not identical also. Several semiconductor introduces below optoelectronic devices commonly used measurement circuit.Semiconductor photoconductive resistance can through large current, be in so usually, need not equipped with amplifier. In the output power of demand is bigger, can use figure 8 shows circuit.Figure 9 (a) with temperature compensation given the photosensitive diode bridge type measuring circuit. When the incident light intensity slow change, the reverse resistance photosensitive diode is the slow change, the change of the temperature will cause the bridge output voltage, must compensate. Drift Picture a photosensitive diode as the test components, another into Windows, in neighboring bridge, the change of the temperature in the arms of the influence of two photosensitive diode, therefore, can eliminate the same output with temperature bridge road drift.Light activated triode incident light in work under low illumination, or hope to getbigger output power, also can match with amplifying circuit, as shown in figure 9 shows.Because even in the glare photosensitive batteries, maximum output voltage also only 0.6 V, still cannot make the next level 1 transistor have larger current output, so must add positive bias, as shown in figure 9 (a) below. In order to reduce the transistor circuit impedance variations, base si-based ones to reduce as much as possible without light, when the reverse bias inherit in parallel a resistor si-based ones at both ends. Or like figure 9 (b) as shown by the positive ge diode produces pressure drop and test the voltage produced when exposed to light, make silicon tube e stack, b the voltage between actuators than 0.7 V, and conduction work. This kind of circumstance also can use silicon light batteries, as shown in figure 10 (c) below. Semiconductor photoelectric element of photoelectric circuit can also use integrated operational amplifier. Silicon photosensitive diode can be obtained by integratingop-amp larger output amplitude, as shown in figure 11 (a) below. When light is produced, the optical output voltage in order to guarantee photosensitive diode isreverse biased, in its positive to add a load voltage. Figure 11. (b) give the photocell transform circuit, because the photoelectric si-based ones short-circuit current and illumination of a linear relationship between, so will it up in the op-amp is,inverse-phase input, using these two potential difference between the characteristicsof close to zero, can get better effect. In the picture shows conditions, the output voltageThe photoelectric element by flux the role of different made from the principle of optical measurement and control system is varied, press the photoelectric element (optical measurement and control system) output nature, namely, can be divided into second analog photoelectric sensor and pulse (switch) photoelectric sensor. Analog photoelectric sensors will be converted into continuous variation of the measure, it is measured optical with a single value relations between analog photoelectric sensor. According to be measured (objects) method detection of target can be divided into transmission (absorption) type, diffuse type, shading type (beam resistance gears) three categories. So-called transmission style means the object to be tested in optical path in constant light source, the light energy through things, part of being measured by absorption, transmitted light onto photoelectric element, such as measured liquid, gas transparency and photoelectric BiSeJi etc; speed.gratifying The so-called diffuse style means the constant light by the light onto the analyte from the object to be tested, and projected onto surfaces reflect on after optoelectronic devices, such as photoelectric colorimetric thermometer and light gauge etc; The so-called shading style means the when illuminant issued by the flux of light analyte covered by a part Jing optoelectronics, make projection on the flux change, change the object to be tested and extent of the position with the light path, such as vibration measurement, the size measurement; And in pulse photoelectric sensor in the sensors, photoelectric element acceptable optical signal is intermittent change, therefore photoelectric element in switch work of the state, the current output it is usually only two steady state of the signal, the pulse form used for photoelectric counting and photoelectric speed measurement and so on.And infrared photoelectric sensor classification and working way generally have thefollowing kinds:1, groove photoelectric sensor put a light emitter and a receiver in a slot face-to-face outfit are on opposite sides of the photoelectric groove. Lighter emits infrared light or visible light, and in unimpeded cases light receptors can receive light. But when tested objects from slot zhongtong obsolete, light occluded, photoelectric switches and action. Output a switch control signal, cut off or connect load current, thus completing a control movement. Groove switch is the overall of detection distance because general structure limits only a few centimeters.2, DuiShe type optoelectronic sensor if you put lighter and receive light is separated, can make the detection distance increase. By a lighter and an inbox light sensor into a photoelectric switch is called DuiShe separate photoelectric switches, referred to DuiShe photoelectric switch. Its detection distance can reach a few meters and even a dozen meters. When using light-emitting device and receive light device are installed in test object through the path of the sides, test object by blocking light path, accept light implement action output a switch control signals.3, reflex plate.it photoelectric switch light-emitting device type and receive light device into the same device inside, in its front pack a reflex plate.the using the reflection principle of complete photoelectric control function is called reflex plate.it reflex (or reflector reflex) photoelectric switch. Under normal circumstances, lighter the light reflected by reflex plate.it is received by accept light; Once the light path be test object to block, accept light, the light is not receive photoelectric switch is action, output a switch control signals.4, diffusion reflective photoelectric switches its detection head with a lighter and also an inbox light ware, but no reflex plate.it ahead. Normally lighter for the light collect light is not found. When test object by blocking the light, and the light reflected light, receive part implement received light signals, output a switch signals.Four, I'm the idea of photoelectric sensorWith the development of science and technology people on measuring accuracy had the higher request, this has prompted the pace with The Times photoelectric sensor have updated, improve the main means photoelectric sensor performance is the application of new materials, new technology manufacturing performance is more superior photoelectric element. For example, today the prototype of the photoelectric sensor is a small metal cylindrical equipment, with a calibration lens, transmitter into receiver focused light, the receiver out of cable to the device got a vacuum tube amplifiers in metal cylinder on the incandescent light bulb inside a small as the light source a strong incandescent lamp sensor. Due to the sensor various defects existing in the fields, gradually faded. To appear, because of it of fiber of excellent performance, then appeared with sensors supporting the use of optical passive components, another fiber without any interference of electromagnetic signal, and can make the sensor of the electronic components and other electrical disturbance in isolation. Have a piece of plastic optical fiber core or glass light core, light outside a metallic core skins and bread this layer metal cortical density lower than light core, so low, the beam refraction in the two materials according to the border (incident Anglewithin a certain range, reflected), is all. Based on optical principle, all beams can be made by optical fiber to transmission. Two incident beam Angle in an Angle (along the fiber length direction within) by multiple reflections from the other end after injection, another incident angles than accept the incident light in metal skin, loss. This accept Angle within the biggest incident Angle than two times, this is because fiber slightly larger from air into density larger fiber materials hitting may have a slight refraction. In light of the optical fiber transmission from inside the influence of fiber bending (whether more than bending radius minimal bending radius). Most optical fiber is flexible, easy to install in the narrow space. Photoelectric sensor is a kind of non-contact measurement small electronic measurement equipment, rely on detect its receives the light intensity change, to achieve measurement purposes, andit's also a vulnerable to external disturbance and lose the measurement accuracy of the device. When be being designed so besides the choice optoelectronic components, still must set GSCC signal and temperature compensating measures used to weaken or eliminate the impact of these factors.Photoelectric sensor must pass a light modulation, like radio waves of light modulation of sends and receives, the radio to a station, can ignore other radio signal sensors without modulation long-focal-length only through the use of mechanical shielded, scenes that receiver transmitter only can receive the emission of light, can make its energy becomes very high. In contrast, through modulation transceivers can ignore ambient light, only to own light or with the same modulation frequencies of light without modulation response. The sensor used to test the infrared rays or around the radiation, if just baked red bottle, in this application situation if use other sensor, may be incorrect actions.Photoelectric sensor due to non-contact, high reliability, etc, and to change in measurement, damage the object to be testedSo since its invention in fields since play a significant role, at present it has been widely used in measuring mechanical quantity, thermal quantity, weight, intelligent vehicle system into etc. Now it in power system automatically grid device plays a very important role, because generator input power grid operation often USES accurate with law, must meet: three-phase line sequence is consistent, frequency, phase agree unanimously, voltage amplitude equal, one of the conditions in system design has been satisfied, after three conditions must also meet to grid, of course, artificially grid is more difficult, photoelectric grid is easier.The development of times, science and technology in the update, photoelectric sensor types are increasing and application domain more and more widely, such as a recent kind of infrared already in intelligent vehicle electrical sensors in to the application, one of which had based on infrared sensor is the core of intelligent vehicle, reflective type infrared sensor using reflex infrared sensor design path detection module and speed monitoring module; Another method based on infrared sensor using the car tracing is to collect infrared sensor data.Photoelectric sensor has cannot be replaced by other sensors superiority, so it development foreground is very good, the application will also become more widespread.光电传感器关键字：光电效应 光电元件 光电特性 传感器分类 传感器应用 摘要：在科学技术高速发展的现代社会中，人类已经入瞬息万变的信息时代，人们在日常生活，生产过程中，主要依靠检测技术对信息经获取、筛选和传输，来实现制动控制，自动调节，目前我国已将检测技术列入优先发展的科学技术之一。
传感器英文文献翻译-光电传感器
———光电传感器 报告人: 学 号： 专 业： 老 师：
Photoelectric sensor
Key word: photoelectric effect photoelectric element photoelectric sensor classification sensor application characteristics . Abstract: in the rapid development of science and technology in the modern society, mankind has into the rapidly changing information era, people in daily life, the production process, rely mainly on the detection of information technology by acquiring, screening and transmission, to achieve the brake control, automatic adjustment, at present our country has put detection techniques listed in one of the priority to the development of science and technology. Because of microelectronics technology, photoelectric semiconductor technology, optical fiber technology and grating technical development makes the application of the photoelectric sensor is growing. The sensor has simple structure, non-contact, high reliability, high precision, measurable parameters and quick response and more simple structure, form etc, and flexible in automatic detection technology, it has been widely applied in photoelectric effect as the theoretical basis, the device by photoelectric material composition.
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中英文对照翻译译文:光电式传感器的应用与发展摘要目前,光电式传感器的应用范围越来越广,这大大促进了光电式传感器的发展。
光电式传感器结构简单而且形式多样。
它具有精度高，响应速度快，非接触等优点。
在本文中，我们分析了光电式传感器的工作原理,介绍了光电式传感器的分类,然后重点介绍了光电式传感器的应用和使用原理,分析了光电式传感器的现状和未来的发展趋势。
关键词光电式传感器，光电式传感器的应用，光电式传感器的发展1 引言光电式传感器是一种将光学元件和电子元件作为检测部分的传感器。
光电检测技术具有精度高，响应速度快，非接触式等优点。
该传感器结构简单，形式灵活多样。
因此，光电式传感器被广泛运用于控制和测试领域。
它可用于检测由于光量变化导致的非电量变化，如光强，辐射温度，气体成分等等。
它也可以通过光的传输，阻隔，反射，干扰来测量各种物理量，如物体的大小，位移，速度，温度等。
所以它是一个具有广泛应用前景的至关重要的灵敏器件。
当使用光电式传感器时，光电式传感器不直接与被测物体接触，光束质量几乎为零，在测量过程中不存在摩擦力，且在被测物体上几乎没有任何压力。
因此，光电传感器在很多应用方面都比其他传感器具有明显的优势。
然而，它的缺点是在某些应用场合中光学器件和电子设备是比较昂贵的，而且在测量过程中对环境条件的要求较高。
近年来，新型光电子器件的不断涌现为光电式传感器的进一步应用开创了新的一页尤其是CCD图像传感器的出现。
2 光电传感器的原理光电传感器是以光电器件作为转换元件的传感器。
该光电传感器的原理是把被测量的变化转换成光信号的变化，然后借助光电元件进一步将光信号转换成电信号的光电组件。
光电传感器一般由光源、光学通路和光电元件三部分组成。
光电传感器的工作过程如图1所示。
图1 光电式传感器的工作过程光电器件的作用是将光信号转换成基于光电效应的电信号。
光电效应是一种物理现象，光照射到某些物质，并导致物体电性质发生重大改变。
它可分为外光电效应和内光电效应。
外光电效应是物体内的电子在光的作用下逸出物体表面的物理现象。
光子是量子“粒子”来描述可见光波的形式。
光子的能量为hv，h是普朗克常数，v是光的频率。
光子通量的光强度相对应。
Einstein方程所描述的外部光电效应：hv=1/2*mv0^2其中m是电子质量，V0是电子逃逸速度。
当光子的能量等于或大于功函数时，就会产生外光电效应。
因此，每个对象都有一个相应的光电临界频率，被称为红色极限频率。
如果它超过了入射光频率的红色极限频率，那么外源的光电流与光强度成比例。
当光照射到物体上，它可以导致电导率发生改变或产生光生电动势，这就是所谓的内部光电效应。
内部光电效应分为光生伏特效应和光电导效应。
光伏效应的作用是使对象在光的影响下具有一定力的方向。
在该作用下的光电子器件是光敏二极管，晶体管，太阳能电池；光电效应是在光线的作用下，电子吸收光子的能量从粘合状态过渡到自由状态，从而导致材料电导率的变化。
光敏电阻器等器件就是基于这样的效果的光电子器件。
3 光电式传感器的分类光电传感器的分类是多种多样的。
光电传感装置根据外光电效应分为光电管和光电倍增管。
根据光电导效应制成了光敏电阻。
根据光电传感器的阻隔效果分为光电二极管和光电晶体管。
根据光电效应的相反过程制成了反向光电二极管。
光电式感应器根据信号的形式可以分为模拟光学传感器和数字光学传感器。
光电式传感器还包括光纤传感器，固态图像传感器等。
图2所示为常见的光电传感器。
图2 常见的光电传感器4 光电传感器的应用随着技术的发展，光电式传感器使用越来越多。
光电传感器在日常生活，工业生产和信息技术中的应用越来越多。
4.1 光源是被测物体的应用光照度E的单位为勒克斯（lux），这是光度学中常用的单位之一，这意味着照明系统的物理对象的曝光程度，它可以被用来测量照度计。
1）红外辐射温度计红外辐射温度计经常应用于非接触式温度测量。
红外辐射温度计即可用于为高温度测量也可用于低于冰点的低温度测量，这也是辐射温度计的趋势。
市售红外测温仪温度范围从-30℃〜3000℃，中间被分成几个不同的规格，你可以根据需要选择合适的型号。
图3所示为红外辐射温度计的形状。
图3 红外辐射温度计的形状2）热电型红外线传感器热电型红外线传感器可以检测到人或动物发送的红外光并输出相应的电信号。
热电型红外线检测装置已被广泛用于红外光谱法，红外遥感和辐射探测器中。
它也可用于能产生远红外辐射的人体检测和报警中。
如防盗门，酒店大堂的自动门，自动灯光控制。
例如：当没有人在房间里时，它会自动关闭空调，饮水机；电视可以判断当没有人在看或有人睡眠时自动关闭电路。
图4所示为热电型红外线传感器的形状。
图4 热电型红外线传感器的形状4.2 被测物体吸收光能的应用在此应用中，被测物体可以吸收光能，根据目标的光能量的减弱程度来实现目标的分析和测量。
1）光电浊度仪光电浊度仪是基于传输衰减和红外光散射的衰减与悬浮泥沙浓度密切相关的原则来实现污泥的浓度和悬浮物测量。
不同类型的污泥和悬浮物有不同的红外光的衰减，我们可以调整发送频率，并使用不同的算法，以满足不同的应用。
2）烟雾报警器没有烟雾时，光敏元件能接收到一个恒定的红外信号。
一旦发生火灾，烟雾进入房间，并阻止一些红外光，光电晶体管输出信号被削弱，这是判断的阈值电路，发出报警信号。
图5所示为烟雾报警器。
图5 烟雾报警器4.3 被测物体反射光通量的应用该传感器采用漫反射的原理。
在这种传感器中，发射器和接收器安装在同一设备上。
由发射器发射的光被目标对象所反射，并充满了各个方向，反射光的一部分反射到接收器，所以可以检测出目标对象。
1）反射式光烟报警器在没有烟雾的情况下，由于红外管垂直于内部涂满了黑色的烟雾吸收材料，所以红外光无法到达红外光敏晶体管。
当烟雾进入烟室，烟产生的固体颗粒对红外光的漫反射，使部分的红外光到达红外光敏晶体管并输出光电流。
2）光电式转速表光电式转速表是反射的光电式传感器，它可以从与被测物体外部相差几十毫米的地方无接触的测量速度。
3）颜色传感器色彩传感器被用于检测一个特定的颜色或对象的位置，它测量颜色时通过与没有颜色的区域进行比较，而不是直接测量。
4.4 被测物体遮光的应用遮光式光电传感器需要两个独立的条件，发光装置安装在一个机箱内，接收机安装在另一个机箱。
发射出来的光从发射装置注入到接收装置，当目标对象遮挡了光的传播，接收器的输出将会改变。
带钢偏差的光电检测器。
当带钢偏移正确的位置时，边缘往往与发送机碰撞，造成钢材的浪费。
当带材处于正确的位置（中间位置）时，放大器的输出电压为零，当带材进入左侧，遮光面积减小，输出电压反映条形的方向和大小的偏差。
带钢偏差的光电检测器，如图6所示。
图6 带钢偏差的光电检测器5 光电式传感器的发展随着半导体技术在60年代的迅速发展，光敏半导体器件发展迅猛。
在此期间，各种光学材料已被充分研究和广泛使用。
人们通过对光电效应及其设备的研究已经开发出多种适合不同场合的光电器件。
再加上由于薄膜技术，表面处理技术和大规模集成电路技术的发展，光电式传感器的制造过程也达到了一个较高的水平，大大降低了产品成本。
在过去的几十年中，红外传感器和其他光学传感设备在航空航天和国防领域获得了广泛的应用。
在未来几年中，主要的传感器技术将在灵敏度，分辨率和整体性能上实现突破。
光电式传感器的应用已经扩展到纺织业，造纸业，印刷，医疗，环保。
传统领域的研究有了新的发展，如红外探测，辐射测量，光纤通信，自动控制等。
红外传感器和微光传感器是使用最广泛的光电式传感器。
红外传感器分辨率的增加，且对制冷的需求降低提高了其可靠性。
微光传感器依赖于传统的图像增强器的提高以及传感器的模拟信号转换为数字信号。
这两种技术的发展趋势是各种多光谱传感器技术的整合，这可以最大限度地发挥个人技术的表现，越来越多的应用到手持设备和无人驾驶汽车等领域。
结合几种不同的光电传感器的长处会发现有很多的优点，但只有它被用来在适当的场合时才可以发挥这些优势。
例如，微光传感器更适合在夜间观察大面积，但不足以检测静态隐藏在树林里的人。
在这种情况下，如果我们用长波红外相机融合微光传感器，那么隐藏在树林里的人将是可见的。
如果我们用另一种短波红外传感器与之融合，那么我们甚至可以识别隐藏在树林里的人的面部特征。
此外，在光电式传感器的另一个主要趋势是增加像素焦平面阵列的数目。
原文:The Application and Development of Photoelectric Abstract: At present, the application of photoelectric sensors are more and more extensive, it also promotes the development of photoelectric sensors. Photoelectric sensor has simple structure and diversity. It has high precision, fast response, non-contact and other advantages. In this paper, we analyze the principle of photoelectric sensors, introduce the classification of photoelectric, and then highlight introduce the application of photoelectric sensors and the use of the principle of photoelectric sensors, analyze the current and future development of photoelectric sensors.Keywords:Photoelectric sensor, the application of photoelectric sensor, the development of photoelectric sensor.1 IntroductionPhotoelectric sensor is the sensor to use the electronic and optical element as the detection component. Photoelectric detection has high precision, fast response, noncontact advantages and so on. The sensor has simple structure, flexible and diverse forms. Therefore, the photoelectric sensor is widely used in the field of control and testing. It can be used to detect the non-electricity which can cause changes in the amount of light, such as light intensity, radiation temperature, gas composition. It can also use light transmission, occlusion, reflection, interference and others to measure a variety of physical quantities, such as object size, displacement, velocity, temperature, etc. So it is an important and sensitive device which has a very wide application. When using the photoelectric sensor, it doesn't directly contact with the measured object and the beam quality is nearly zero, there is no friction in the measurement and almost no pressure on the measured object. Therefore, photoelectric sensors has obvious advantages than other sensors in many applications. However, its drawback is that optical devices and electronic devices are more expensive in some applications, and environmentalconditions require higher on the measurement. In recent years, new optoelectronic devices are been emerging, particularly the birth of CCD image sensor, that creates a new field for the further application of photoelectric sensors.2 The Principle of Photoelectric SensorPhotoelectric sensors use photoelectric elements as sensor conversion devices. The principle of photoelectric sensor is to reflect the measured objects changes by light signal, and then convert the light signal into electrical signals by optoelectronic components. Usually the photoelectric sensor is composed by light source, optical access and optical components. The working process of photoelectric sensor is shown in Figure 1.Fig. 1. The working process of photoelectric sensorThe role of optoelectronic devices is to convert the optical signal into electrical signal, which is based on the photoelectric effect. Photoelectric effect is a physical phenomenon that the light shines on certain substances and causes the material to change in the electrical characteristics. It can be divided into external and internal photoelectric effect.External photoelectric effect is the physical phenomena that the object's electron escape surface of the object and emits outside under the influence of light. Photon is in the form of quantum "particles" to describe visible light waves. Photon energy is hv, h is the Planck constant, v is the optical frequency. Photon flux corresponds to light intensity. External photoelectric effect is described by the Einstein equation:hv=1/2*mv0^2Where m is electron quality, v0 is electronic escape velocity. When the photon energy is equal to or greater than the work function, the external photoelectric effect can be generated. So each object has a corresponding effect on the photoelectric threshold frequency of light, known as the red limit of frequency. For more than the red limit of theincident light frequency, exogenous photocurrent is proportional to light intensity.When light shines on the object, it can cause the resistivity to change or generate photo-emf which is called the internal photoelectric effect. The internal photoelectric effect is divided into photovoltaic effect and photoconductivity effect. Photovoltaic effect is the phenomenon that makes objects have a certain direction of the force under the influence of light. Optoelectronic devices based on the effects are photosensitive diodes, transistors, photovoltaic cells; photoconductive effect is that under the influence of light, electrons absorb the photon energy from the bonding state of transition to a free state, which leads to material changes in conductivity. Optoelectronic devices based on this effects are photosensitive resistor and so on.3 The Classification of Photoelectric SensorPhotoelectric sensor classification is varied. Photoelectric sensing devices based on external photoelectric effect are photoelectric tubes and photomultiplier tubes. Photoelectric sensors based on photoconductive effects are photoresistors. Photoelectric sensors based on barrier effects are based on photodiodes and phototransistors. Photoelectric sensors based on reverse side of the photoelectric effect are reverse photodiodes. Photoelectric sensors can be classified into analog optical sensors and digital optical sensors by signal forms. Photoelectric sensors also include fiber optic sensors, solid image sensors and so on. Figure 2 shows common photoelectric sensors.Fig. 2. Common photoelectric sensors4 The Application of Photoelectric SensorWith the development of technology, the use of photoelectric sensors is more and more. Photoelectric sensors have a growing number of applications in everyday life, industrial production and information technology.4.1 The Application that Light Source Is the Measured ObjectThe unit of light illumination E is lx (lux), which is one of the units commonly used in photometry, it means the degree of exposure of the illuminated physical object, it can be used to measure the illuminance meter.1)The infrared radiation thermometerInfrared radiation thermometer has many applications in non-contact temperature measurement. Infrared radiation thermometer can be used for both high temperature measurement and below freezing temperature measurement, this is also the trend of radiation thermometer. Commercially available infrared thermometer temperature is range from -30 ℃ ~ 3000 ℃, the middle is divided into several different specifications, you can select the appropriate model according to the need. Figure 3 shows the shape of the infrared radiation thermometer.2) Pyroelectric sensorPyroelectric infrared sensor can detect infrared light transmitted by person or animal and output corresponding electric signal. Pyroelectric infrared detection devices have been widely used in infrared spectroscopy, infrared remote sensing and radiation detectors.Fig. 3. The shape of the infrared radiation thermometerIt is also used in human detection, alarm, which can produce farinfrared radiation, such as security doors, hotel lobby automatic doors, automatic light control. For example: it will automatically turn off air conditioners, drinking fountains when no one is in the room; TV can judge that no one is watching or person has to sleep and automatically shutdown the circuit. Figure 4 is the shape of the pyroelectric sensor.Fig. 4. The shape of the pyroelectric sensor4.2 The Application That the Measured Object Absorbs Light EnergyIn this application, the measured object can absorb light energy, according to the weakening degree of light energy to achieve the target analyte measurement.1) Photoelectric turbidimeterPhotoelectric turbidimeter is based on the principle that the transmission attenuation and scattering attenuation of infrared light are relate to the suspended sediment concentration to achieve the concentration of sludge and suspended solids measurements. Different types of sludge and suspended matter have different attenuation to infrared light, we can adjust the transmission frequency and use different algorithms to meet different applications.2) Smoke alarmNo smoke, a photosensitive element receives a constant infrared LED transmitter. In the event of fire, smoke comes into the testing room and blocks some of the infrared light, the phototransistor output signal is weakened, it is judging by the threshold circuit, an alarm signal is occured. Figure 5 is smoke alarms.Fig. 5. Smoke alarms4.3 The Application That the Measured Object Reflects FluxThis sensor uses the principle of diffuse reflection. In such sensors, emitter and receiver mounted on the same device. The light emitted by the emitter is reflected by the target object, the reflected light is in all directions, part of the reflected light reflects into the receiver, so that can detect the target object.1) Reflective smoke alarmIn the absence of smoke, due to infrared tube is perpendicular to the interior and painted black smoke absorption material, so infrared LED infrared light can not reach the infrared phototransistor. When the smoke comes into the smoke chamber, solid particles of the smoke produce diffuse reflection towards infrared light, so that part of the infrared light reaches the phototransistor and light current output.2) Photoelectric tachometerPhotoelectric tachometer is reflective photoelectric sensor, which can be tens of millimeters away from the measured object outside and measure the speed without contact.3) Color sensorsColor sensors are used to detect a specific color or spot on the object, it measures the color by comparing with the zone without color, rather than direct measures color. 4.4 The Application That Measured Object Blocks the LightThe shading photoelectric sensor needs two separate cases, light-emitting device is installed in a chassis, receiver is installed in another chassis. The light emited from emitter injects to the receiver, when the target object blocks the light, the receiver's output will change.The photoelectric detector of strip deviation. When the strip goes wrong road, the edge often collides with the sending machine, resulting in waste. When the strip is in the correct position (center position), the amplifier output voltage is zero; when the strip goes left-side, the shading area is reduced, the output voltage reflects the deviation of strip direction and size. The photoelectric detector of strip deviation is shown in Figure 6.Fig. 6. The photoelectric detector of strip deviation5 The Development of Photoelectric SensorPhotosensitive semiconductor devices rapidly develop with the development of semiconductor technology in the 60's. During this period, a variety of optical materials have been fully studied and widely used. People have developed a variety of optoelectronic devices suitable for different occasions by the research about the principle of the photoelectric effect and device. Photoelectric sensor manufacturing process also achieves a high level with the development of film technology, surface technology and large scale integrated circuit technology, and the cost of the product is greatly reduced. In the past few decades, infrared sensors and other optical sensing devices access to a wide range of applications in the field of aerospace and defense. In the next few years, the main sensor technology will be breakthroughs in the sensitivity, resolution and overall performance. Photoelectric sensor applications has been extended to the textile, paper making, printing, medical, and environmental protection. The study of traditional areas has a new development, such as infrared detection, radiation measurement, optical fiber communication, automatic control and so on.Infrared sensor and low light level sensor are two of the most widely used photoelectric sensors. The resolution of infrared sensors is increasing, and the reliability is improved with reducing the demand for cooling. Low light level sensors rely on the traditional image intensifier to improve, and the sensor's analog signals convert to digital signals. The development trend of the two technologies is the integration of a variety of multispectral sensors technology that can maximize the performance of individual technologies, more and more have applied to handheld devices and unmanned vehiclesand other fields.Combination of several different photoelectric sensors' strong points has many advantages, but only it is used in an appropriate forum that can play these advantages. For example, low light level sensors are more suitable for observing a wide area at night, but are insufficient to detect static person hidden in the woods. In this case, if we fuse long-wave infrared camera with low light level sensors, the staff after trees will be visible. If we fuse another short-wave infrared sensor, we can even identify the person's facial features after trees.In addition, another major trend of the photoelectric sensor is to increase the number of pixels focal plane arrays.。