传感器英文简介
（完整版）传感器专业名词英文解释
（完整版）传感器专业名词英⽂解释1. Briefly define the following terms1) TransducerA transducer is a device that converts a signal from one physicalform to a corresponding signal having a different physical form .2) SensorA sensor converts a physical signal into an electrical signal (i.e., amicrophone).3) ActuatorAn actuator is a device that converts electrical energy into physical energy (i.e.,a loudspeaker).4) LinearityThe linearity describes the closeness between the calibration curve and a specified straight line.5) SensitivityThe sensitivity is defined in terms of the relationship between input physicalsignal and output electrical signal. It is generally the ratio between a smallchange in electrical signal to a small change in physical signal. The sensitivity isthe slope of the calibration curve.6) HysteresisThe hysteresis refers to the difference between two output values thatcorrespond to the same input, depending on the direction (increasing ordecreasing) of successive input values. That is, similarly to the magnetizationin ferromagnetic materials, it can happen that the output corresponding to agiven input depends on whether the previous input was higher or lower than thepresent one.Some sensors do not return to the same output value when the input stimulus iscycled up or down. The width of the expected error in terms of the measuredquantity is defined as the hysteresis.7) RepeatabilityThe repeatability is the closeness of agreement between successive resultsobtained with the same method under the same conditions and in a short timeinterval.%100y σ)3~2(δFS ?=Rδ—sample standard deviation8) Strain (mechanical)Fractional change in length ΔL/L.9) Gage factorThe gage factor is defined as the fractional change in resistance divided by the strain.10) Piezoresistive effectThe change in resistivity as a result of a mechanical stress is called thepiezoresistive effect.11)direct piezoelectric effect.the phenomenon of generation of a voltage under mechanical stress is referred to as the piezoelectric effect.12)converse piezoelectric effect.The mechanical strain produced in the crystal under electric stress is called the converse piezoelectric effect.13)Numerical ApertureThe "acceptance cone" defines how much light will be accepted into the fiber andultimately how much remains in the fiber, and is referred to as the numerical aperture. 14)Extrinsic sensorThe optical fiber plays no part in achieving the modulating but simply acts as atransmission medium ; these are extrinsic sensors.15)Intrinsic sensors (fiber optic sensor)The optical fiber plays a major role in modulating the energy from the source; these are referred to as intrinsic sensors.16)Humiditya quantity representing the amount of water vapor in the atmosphere or a gas17)Absolute humidityAbsolute humidity is the mass of water vapor per unit volume of air.18)Relative humidityThe ratio of the actual vapor density to the theoretical maximum (saturation) vapordensity at the same temperature, expressed as a percentage. The relative humidity is the ratio of the actual vapor pressure to the saturation vapor pressure at given temperature. 19)Peltier effectWhen two dissimilar metals are connected together, a small voltage called athermojunction voltage is generated at the junction. This is called the Peltier effect.20)Law of Homogeneous ConductorsFor a given pair of homogeneous conductors forming a closed loop, the Seebeck emf depends only on the temperatures of the junctions, and not on the temperature distribution along the length of the conductors.21)Law of intermediate metalsA third (intermediate) metal wire can be inserted in series with one of the wires withoutchanging the voltage reading (provided that the two new junctions are at the sametemperature).If there is a third metal introduced into the thermocouple circuit , it will not adverselyeffect the reading, if and only if the two junctions of the third metal are at the sametemperatures .22)Bernoulli’s theoremBernoulli’s equation states that energy is approximately conserved across a constriction ina pipe.Bernoulli’s equation: P/(ρ?g) + ?v2/g + y = constant(ρ=density;g=acceleration of gravity ; v=fluid velocity; y=elevation )2. Describe the following devices and how they work1) Strain gageThe strain gauge usually consists of wire, baking, thinpaper, and lead welded. The wireis arranged in the form of a grid in order to obtain higher resistances.2) Parallel plate Capacitive SensorThe parallel plate Capacitive Sensor is a function of the distance d (cm) between theelectrodes of a structure, the surface area A (cm2) of the electrodes, and the permittivity ε0(F/m 1085.812-?for air) of the dielectric between the electrodes; therefore:d Ad AC 0r εεε==3) Differential Capacitive SensorA differential capacitor consists of two variable capacitors so arranged that they undergothe same change, but in opposite directions. The amplifier circuit, depending on itsconfiguration, can generate a voltage proportional to C1 - C2 or C1/C2 or (C1 - C2)/(C1 +C2).4) Variable Reluctance SensorsA typical single-coil variable-reluctance displacement sensor is illustrated in the Figurebelow. The sensor consists of three elements: a ferromagnetic core, a variable air gap, anda ferromagnetic plate.Based on change in the reluctance of a magnetic flux path. Self-inductance L of the coil is: Reluctance can be given as: 5) Variable-Reluctance TachogeneratorsIt consists of a ferromagnetic, toothed wheel attached to a rotating shaft, a coil and amagnet. The wheel rotates in close proximity to the pole piece, thus causing the flux linkedby thecoil to change. The sensors output depends on the speed of the rotation of the wheeland the number of teeth.6) LVDTAn LVDT consists of three coils, a form and a core. The coils are wound on a hollow form.The primary is excited by some ac source. Flux formed by the primary is linked to the twosecondary coils, inducing an ac voltage in each coil. A core is inside the former. It canslide freely through the center of the form.In many applications, the two secondary coils are connected in series opposition.Then the two voltages will subtract; that is, the differential voltage is formed. When thecore is centrally located, the net voltage is zero. When the core is moved to one side, thenet voltage will increase.7) Compression Mode Piezoelectric Accelerometers Upright compression designs sandwich the piezoelectric crystal between a seismic mass2m WL R =0m l R S µµ=and rigid mounting base. A pre- load stud or screw secures the sensing element to themounting base.When the sensor is accelerated, the seismic mass increases or decreases the amount of compression force acting upon the crystal, and a proportional electrical output results.8)Shear mode accelerometerShear mode accelerometer designs bond, or “sandwich,” the sensing material between a center post and seismic mass. A compression ring or stud applies a preload force required to create a rigid linear structure. Under acceleration, the mass causes a shear stress to be applied to the sensing material. This stress results in a proportional electrical output by the piezoelectric material. They represent the traditional or historical accelerometer design.9)PsychrometerA psychrometer contains two identical thermometers. One sensor, the dry bulb ,measures the ambient temperature. The other sensor, the wet bulb, is in a wetted condition.In operation, water evaporation cools the wetted thermometer, resulting in a measurable difference between it and the ambient, or dry bulb measurement. When the wet bulbreaches its maximum temperature depression, the humidity is determined by comparing the wet bulb/dry bulb temperatures on a psychrometric chart10)Dunmore sensorThe Dunmore sensor uses a dilute lithium chloride solution in a polyvinylacetate binder on an insulating substrate. The resistance of the sensor, measured between a bifilar grid, is a function of the r.h. of the surrounding air.11)MOS CapacitorCCDs are typically fabricated on a p-type substrate. In order to implement the “buried” channel a thin n-type region is formed on its surface. A insulator, in the form of a silicon dioxide layer is grown on top of the n-region. Thecapacitor is finished off by placing one or more electrodes, also called gates, on top of the insulating silicon dioxide.12)Full frame transfer (FFT)It consists of a parallel CCD shift register, a serial CCD shift register and a signal sensing output amplifierThe image pixel are vertically transferred into a horizontal serial register, and the charges are horizontally shifted out.13)Interline transfer (ILT)The readout regions are interspaced between the imaging regions, and are shielded from the light.At the end of the integration period, the charges are transferred horizontally to the vertical readout registers in parallel, and then read out line-by-line in a manner similar to FFT.ILT does avoid smear but with the cost of the sensitive imaging areas.14)Frame transfer (FT)The array is grouped into two sections: the image section and the storage section. These two sections are identical, except that the storage section is shielded from the light. During the readout, charges are transfered line-by-line into the storage section by applying the same clocking to both sections. At the end of the integration period, charges in the storagesection are transferred line-by-line a manner similar to FFT.15)proximity sensorsProximity sensors detect objects that are near but without touching them. These sensors are used for near-field robotic operations.16)Time-of-flight sensorsTime-of-flight sensors estimate the range by measuring the time elapsed between thetransmission and return of a pulse17)Triangulation sensorsTriangulation sensors measure range by detecting a given point on the object surface from two different points of view at a known distance from each other. Knowing this distance and the two view angles from the respective points to the aimed surface point, a simple geometrical operation yields the range.18)Thermal Infrared DetectorsThermal infrared detectors convert incoming radiation into heat, raising the temperature of the thermal detector.19)Photon-type detectorsPhoton-type detectors react to the photons emitted by the object. The infrared radiation causes changes in the electrical properties of photon-type detectors.There are two main types of photon infrared detectors. One is called Photoconductive detector, which exhibit increased conductivity with received radiation. Another is named as Photovoltaic detector, this device converts received radiation into electric current.20)shock tubeConstruction of a shock tube is quite simple: it consists of a long tube, closed at both ends, separated into two chambers by a diaphragm, as shown in the Fig. below. A pressure differential is built up across the diaphragm, and the diaphragm is burst, either directly by the pressure differential or initiated by means of an externally controlled probe. Rupturing of the diaphragm causes a shock wave.The shock tube provides the nearest thing to a transient pressure “standard.”21)ThermocoupleA thermocouple consists of two electrical conductors made of different metals that are joined at one end.Note particularly that two junctions are always required. In general, one sense the desired or unknown temperature; this one we shall call the hot or measuring junction. The second will usually be maintained at a known fixed temperature; this one we shall refer to as the cold or reference junction. When the two junctions are at different temperatures, a voltage is developed across the junction.22)Bimetallic strip thermometerTwo dissimilar metals are bonded together into what is called a bimetallic strip. Since two metals have different coefficient of thermal expansion, one metal will expands more than does another metal as temperature increases, causing the bimetallic strip to curl upwards as sketched.23)RTDA resistance temperature detector is basically either a long, small diameter metal wirewound in a coil or an etched grid on a substrate, much like a strain gage. The resistance ofan RTD increases with increasing temperature.24)Three-wire BridgeA clever circuit designed to eliminate the lead wire resistance error is called a three-wireRTD bridge circuit, as sketched to the right.If wires A and B are perfectly matched in length (wires A and B have the same length, and thus the same resistance,), their impedance effects will cancel because each is in anopposite leg of the bridge. The third wire, C, acts as a sense lead and carries no current.25)ThermistorA thermistor is similar to an RTD, but a semiconductor material is usedinstead of a metal. A change in temperature causes the electrical resistance of the semiconductor material to change. P ositive temperature coefficient (PTC) and and negative temperature coefficient (NTC) units are available.26)Seismic (Absolute) Acc eleration PickupsIt consistis of a mass, a spring, and a damper arrangement, as shown in the Figure below.Fig……..y(t）= the absolute displacement of the mass Mx(t）= the absolute displacement of the basez-y=)()(txtz —the relative motion between the mass and the basem —massc —damping constantk —spring constantSeismic (Absolute) Displacement PickupsThe relative displacement z (the output of the sensor) is proportional to the applied displacement. A low value of ωn is needed (ωn should be much less than the lowest vibration frequency for accurate displacement measurement. )Seismic AccelerometerThe relative displacement z ( the output of the sensor) is proportional to the appliedacceleration. a high ωn is needed to measure accurately high-frequency. Increasing ωn will increase the range of frequency for which the amplitude-ratio curve is relatively flat;27)Seismic Velocity Pickup (moving coil type)One type of velocity transducer is based on a linear generator. When a coil cuts the magnetic field lines around a magnet, a voltage is induced in the coil, and this voltage is dependent on the speed of the coil relative to the magnet. The velocity pickup is designed like a displacement pickup, to have a low value of wn and to operate at angular frequencies well above wn so that the motion of the seismic mass is virtually the same as that of the casing but (almost) opposite in phase.28)The Orifice Plate FlowmetersAn orifice plate is a restriction with an opening smaller than the pipe diameter which is inserted in the pipe; Because of the smaller area the fluid velocity increases, causing acorresponding decrease in pressure.The flow ratee can be calculated from the measured pressure drop across the orifice plate 29)Ultrasonic Flowmeters Ultrasonic Doppler Method:Doppler Equation :v f= K ? Δf ;Doppler ultrasonic flowmeters reflect ultrasonic energy from particles, bubbles and/or eddies flowing in the fluid.Ultrasonic Transit-Time Method：The time difference between ultrasonic energy moving upstream and downstream in the fluid is used to determine fluid Velocity.Because transmitter-receiver B is situated downstream withrespect to A, the sound wave train from A to B will arrive soonerthan the train from B to A . This implies that the execution timefrom A to B is shorter than that from B to A.30)Electromagnetic FlowmetersThe measurement principle is based on Faraday’s Law of Magnetic Induction :ahomogeneous magnetic field is built up. An electrically conducting liquid flowsthrough this magnetic field.By the movement of the electrical conductor (liquid) a current gets induced which isproportional to the average flow velocity and the magnet field strength.。
传感器英文
传感器英文SensorsIntroductionSensors are devices that detect and respond to physical or chemical stimuli in the environment, converting them into signals that can be processed by electronic systems. They are essential components of many modern technologies, including consumer electronics, industrial machinery, and environmental monitoring systems. The field of sensors is continually evolving, driven by advances in materials science, microfabrication techniques, and signal processing algorithms. This article provides an overview of the different types of sensors and their applications in various fields.Types of SensorsSensors can be classified based on the type of stimulus they detect, and the way they convert it into an electrical signal. The following are some of the most common types of sensors:Optical Sensors: These sensors detect light or other forms of electromagnetic radiation, such as infrared or ultraviolet radiation. They are used in applications such as proximity sensing, color detection, and machine vision.Temperature Sensors: These sensors measure changes in temperature and are used in applications such as HVAC systems, refrigeration, and medical devices.Pressure Sensors: These sensors measure changes in pressure, either absolute or relative, and are used in applications such as automotive systems, industrial machinery, and medical devices.Flow Sensors: These sensors measure the flow rate of fluids and are used in applications such as water meters, fuel flow meters, and medical devices.Acoustic Sensors: These sensors detect sound waves and are used in applications such as noise monitoring, speech recognition, and sonar systems.Chemical Sensors: These sensors detect changes in the chemical composition of gases or liquids and are used in applications such as gas detection, water quality monitoring, and medical diagnostics.Biological Sensors: These sensors detect changes in biological systems, such as the concentration of biomolecules or the electrical activity of cells. They are used in applications such as biosensors, drug discovery, and medical diagnostics.Motion Sensors: These sensors detect changes in motion, either acceleration or velocity, and are used in applications such as robotics, gaming, and sports performance analysis.In addition to the above categories, sensors can be further classified based on their operating principles, such as capacitive, resistive, inductive, or piezoelectric. Each type of sensor has its advantages and limitations, and the choice of sensor depends largely on the specific application requirements.Applications of SensorsSensors are used in a wide range of applications, from consumer electronics to industrial automation to environmental monitoring. Some of the most common applications of sensors are:Smartphones and Wearables: Modern smartphones incorporate a variety of sensors, including accelerometers, gyroscopes, magnetometers, and proximity sensors, to enable features such as motion sensing, face recognition, and augmented reality. Wearable devices, such as fitness trackers and smartwatches, also use sensors to monitor physical activity, heart rate, and sleep patterns.Automotive Systems: Sensors play a critical role in modern automobiles, helping to monitor and control various parameters such as engine performance, emissions, airbag deployment, and driver behavior. Advanced driver assistance systems (ADAS) use sensors such as cameras, radar, and lidar to enable features such as adaptive cruise control, lane departure warning, and collision avoidance.Industrial Automation: Sensors are used extensively in industrial machinery to monitor parameters such as temperature, pressure, flow rate, and vibration. They enable real-time monitoring and control of manufacturing processes, improving reliability, efficiency, and safety.Medical Devices: Sensors are used in a variety of medical devices, from blood pressure monitors to glucose meters to MRI machines. They enable precise measurement and monitoring of physiological parameters, improving diagnosis and treatment outcomes.Environmental Monitoring: Sensors are used to monitor air and water quality, weather conditions, and other environmental parameters. They enable early detection of pollution or hazardous conditions, and help to protect public health and safety.Security and Surveillance: Sensors are used in surveillance cameras, motion detectors, and access control systems to detect and respond to unauthorized activity. They provide an effective means of enhancing security and safety in public spaces and private property.ConclusionSensors are essential components of many modern technologies, enabling precise measurement and control of physical and chemical parameters in the environment. Their applications span a wide range of industries, from consumer electronics to industrial automation to environmental monitoring. As technologies continue to evolve, sensors are likely to play an even more significant role in shaping the world around us.。
传感器中英文介绍
传感器中英文介绍Company Document number：WTUT-WT88Y-W8BBGB-BWYTT-19998. sensorssensors(English name: transducer/sensor) is a kind of detection device, can feel the measured information, and will feel information transformation according to certain rule become electrical signal output, or other form of information needed to satisfy the information transmission, processing, storage, display, record and control requirements.Sensor's features include: miniaturization, digital, intelligent, multi-functional, systematic and network. It is the first step of automatic detection and automatic control. The existence and development of the sensor, let objects have sensory, such as touch, taste and smell let objects become live up slowly. Usually according to its basic cognitive functions are divided into temperature sensor, light sensor, gas sensor, force sensor, magnetic sensor, moisture sensor, acoustic sensor, radiation sensitive element, color sensor and sensor etc. 10 major categories.temperature transducerTemperature sensors (temperature transducer) refers to can feel temperature translates into usable output signal of the sensor. The temperature sensor is the core part of the temperature measuring instrument, wide variety. According to measuring methods could be divided into two types: contact and non-contact, according to the sensor material and electronic component features divided into two categories, thermal resistance and thermocouple.1 principle of thermocoupleThermocouple is composed of two different materials of metal wire, the welded together at the end. To measure the heating part of the environment temperature, can accurately know the temperature of the hot spots. Because it must have two different material of the conductor, so called the thermocouple. Different material to make the thermocouple used in different temperature range, their sensitivity is also each are not identical. The sensitivity of thermocouple refers to add 1 ℃ hot spot temperature changes, the output variation of potential difference. For most of the metal material support thermocouple, this value about between 5 ~ 40 microvolt / ℃.As a result of the thermocouple temperature sensor sensitivity has nothing to do with the thickness of material, use very fine material also can make the temperature sensor. Also due to the production of thermocouple metal materials have good ductility, the slight temperature measuring element has high response speed, can measure the process of rapid change.Its advantages are:(1)high precision measurement. Because of thermocouple direct contact with the object being measured, not affected by intermediate medium.(2)the measurement range. Commonly used thermocouple from 1600 ℃ to50 ℃ ~ + sustainable measurement, some special thermocouple minimum measurable to - 269 ℃ ., gold iron nickel chrome), the highest measurable to + 2800 ℃ (such as tungsten rhenium).(3) simple structure, easy to use. Thermocouple is usually composed of two different kinds of metal wire, but is not limited by the size and the beginning of, outside has protective casing, so very convenient to use. The thermocouple type and structure of the form.2. The thermocouple type and structure formation(1)the types of thermocoupleThe commonly used thermocouple could be divided into two types: standard thermocouple and non-standard thermocouple. Standard thermocouple refers to the national standard specifies its thermoelectric potential and the relationship between temperature, permissible error, and a unified standard score table of thermocouple, it has with matching display instrument to choose from. Rather than a standard thermocouple or on the order of magnitude less than the range to use standardized thermocouple, in general, there is no uniform standard, it is mainly used for measurement of some special occasions.Standardized thermocouple is our country from January 1, 1988, thermocouple and thermal resistance of all production according to IEC international standard, and specify the S, B, E, K, R, J, T seven standardization thermocouple type thermocouple for our country unified design.(2)to ensure that the thermocouple is reliable, steady work, the structure of thermocouple requirements are as follows:①of the two thermocouple thermal electrode welding must be strong;②two hot electrode should be well insulated between each other, in case of short circuit;③compensation wires connected to the free cod of a thermocouple to convenient and reliable;④protect casing thermal electrodes should be able to make sufficient isolation and harmful medium.3.The thermocouple cold end temperature compensationDue to the thermocouple materials are generally more expensive (especially when using precious metals), and the temperature measurement points are generally more far, the distance to the instrument in order to save materials, reduce cost, usually adopt the compensating conductor) (the free end of the cold junction of the thermocouple to the steady control of indoor temperature, connected to the meter terminals. It must be pointed out that the role of the thermocouple compensation wire extension hot electrode, so that only moved to the control room of the cold junction of the thermocouple instrument on the terminal, it itself does not eliminate the cold end temperature change on the influence of temperature, cannot have the compensation effect. So, still need to take some of the other correction method to compensate of the cold end temperature especially when t0 indicates influence on measuring temperature 0 ℃.Must pay attention to when using thermocouple compensating conductor model match, cannot be wrong polarity, compensation conductor should be connected to the thermocouple temperature should not exceed 100 ℃.传感器传感器（名称：transducer/sensor）是一种检测装置，能感受到被测量的信息，并能将感受到的信息，按一定规律变换成为电信号或其他所需形式的信息输出，以满足信息的传输、处理、存储、显示、记录和控制等要求。
传感器英文含义
o MK Sensors 传感器▪SENSOR-ACCELERATOR PEDAL POSITION 加速踏板位置传感器▪▪SENSOR-AMBIENT AIR TEMPERATURE 室外温度传感器▪▪SENSOR-CAMSHAFT POSITION 1 凸轮轴位置传感器1▪SENSOR-CAMSHAFT POSITION 2 凸轮轴位置传感器2▪▪SENSOR-CRANKSHAFT POSITION 曲轴位置传感器▪▪SENSOR-ENGINE COOLANT TEMPERATURE 冷却液温度传感器▪SENSOR-EVAPORATOR TEMPERATURE 蒸发器温度传感器▪▪SENSOR-FRONT IMPACT-LEFT 左前碰撞传感器▪SENSOR-FRONT IMPACT-RIGHT 右前碰撞传感器▪▪SENSOR-INFRARED 红外线传感器▪▪SENSOR-INPUT SPEED 输入速度传感器▪SENSOR-OUTPUT SPEED 输出速度传感器▪▪SENSOR-INTAKE AIR TEMPERATURE 进气温度传感器▪▪SENSOR-KNOCK 爆震传感器▪▪SENSOR-MANIFOLD ABSOLUTE PRESSURE 歧管绝对压力传感器▪SENSOR-OIL TEMPERATURE 油温传感器▪▪SENSOR-OXYGEN 1/1 氧传感器一排1▪SENSOR-OXYGEN 1/2 氧传感器一排2▪▪SENSOR-SIDE IMPACT-LEFT 1 侧碰撞传感器左1 ▪SENSOR-SIDE IMPACT-LEFT 2 侧碰撞传感器左2 ▪▪SENSOR-SIDE IMPACT-RIGHT 1 侧碰撞传感器右1 ▪SENSOR-SIDE IMPACT-RIGHT 2 侧碰撞传感器右2 ▪▪SENSOR-WHEEL SPEED-ABS-LEFT FRONT 左前ABS轮速传感器▪SENSOR-WHEEL SPEED-ABS-LEFT REAR 左后ABS轮速传感器▪▪SENSOR-WHEEL SPEED-ABS-RIGHT FRONT 右前ABS轮速传感器▪SENSOR-WHEEL SPEED-ABS-RIGHT REAR 右后ABS轮速传感器▪▪TRANSDUCER-A/C PRESSURE 空调压力传感器。
sensor 翻译
sensor 翻译sensor 翻译为传感器，是一种能够感知和测量环境中各种物理量和信号的装置或设备。
传感器通常用于将物理量转换为电信号，然后通过电子电路进行处理和分析。
它广泛应用于各个领域，包括工业自动化、医疗、交通、农业等。
以下是一些常见的传感器及其用法和中英文对照例句：1. 温度传感器 (Temperature Sensor)：用于测量环境或物体的温度。
- The temperature sensor accurately measures the room temperature. (温度传感器准确地测量室温。
)- The car's engine temperature sensor alerted the driver of overheating. (汽车引擎温度传感器提醒驾驶员发生过热。
)2. 光传感器(Light Sensor)：用于检测光照强度或光线的存在与否。
- The light sensor automatically adjusts the screen brightness based on ambient light. (光传感器根据环境光自动调节屏幕亮度。
)- The security system's light sensor triggered the outdoor lights when it detected movement. (安全系统的光传感器在检测到运动时触发室外灯光。
)3. 压力传感器 (Pressure Sensor)：用于测量物体或环境的压力。
- The pressure sensor in the car's tire warns the driver whenthe tire pressure is low. (汽车轮胎的压力传感器在轮胎压力过低时警告驾驶员。
)- The pressure sensor accurately measures the fluid pressure in the pipeline. (压力传感器准确测量管道中的流体压力。
ccd
CCD传感器及其应用CCD简介CCD，英文全称：Charge-coupled Device，中文全称：电荷耦合元件。
可以称为CCD图像传感器。
CCD是一种半导体器件，能够把光学影像转化为数字信号。
CCD上植入的微小光敏物质称作像素（Pixel）。
一块CCD上包含的像素数越多，其提供的画面分辨率也就越高。
CCD的作用就像胶片一样，但它是把图像像素转换成数字信号。
CCD上有许多排列整齐的电容，能感应光线，并将影像转变成数字信号。
经由外部电路的控制，每个小电容能将其所带的电荷转给它相邻的电容。
CCD广泛应用在数位摄影、天文学，尤其是光学遥测技术、光学与频谱望远镜，和高速摄影技术如Lucky imaging。
CCD 在摄像机、数码相机和扫描仪中应用广泛。
CCD功能特性CCD图像传感器可直接将光学信号转换为数字电信号，实现图像的获取、存储、传输、处理和复现。
其显著特点是：1.体积小重量轻；2.功耗小，工作电压低，抗冲击与震动，性能稳定，寿命长；3.灵敏度高，噪声低，动态范围大；4.响应速度快，有自扫描功能，图像畸变小，无残像；5.应用超大规模集成电路工艺技术生产，像素集成度高，尺寸精确，商品化生产成本低。
因此，许多采用光学方法测量外径的仪器，把CCD器件作为光电接收器。
CCD从功能上可分为线阵CCD和面阵CCD两大类。
线阵CCD通常将CCD内部电极分成数组，每组称为一相，并施加同样的时钟脉冲。
所需相数由CCD芯片内部结构决定，结构相异的CCD可满足不同场合的使用要求。
线阵CCD有单沟道和双沟道之分，其光敏区是MOS电容或光敏二极管结构，生产工艺相对较简单。
它由光敏区阵列与移位寄存器扫描电路组成，特点是处理信息速度快，外围电路简单，易实现实时控制，但获取信息量小，不能处理复杂的图像(线阵CCD见图1-3所示)。
面阵CCD的结构要复杂得多，它由很多光敏区排列成一个方阵，并以一定的形式连接成一个器件，获取信息量大，能处理复杂的图像。
传感器中英文介绍
. sensorssensors(English name: transducer/sensor) is a kind of detection device, can feel the measured information, and will feel information transformation according to certain rule become electrical signal output, or other form of information needed to satisfy the information transmission, processing, storage, display, record and control requirements.Sensor's features include: miniaturization, digital, intelligent, multi-functional, systematic and network. It is the first step of automatic detection and automatic control. The existence and development of the sensor, let objects have sensory, such as touch, taste and smell let objects become live up slowly. Usually according to its basic cognitive functions are divided into temperature sensor, light sensor, gas sensor, force sensor, magnetic sensor, moisture sensor, acoustic sensor, radiation sensitive element, color sensor and sensor etc. 10 major categories.temperature transducerTemperature sensors (temperature transducer) refers to can feel temperature translates into usable output signal of the sensor. The temperature sensor is the core part of the temperature measuring instrument, wide variety. According to measuring methods could be divided into two types: contact and non-contact, according to the sensor material and electronic component features divided into two categories, thermal resistance and thermocouple.1 principle of thermocoupleThermocouple is composed of two different materials of metal wire, the welded together at the end. To measure the heating part of the environment temperature, can accurately know the temperature of the hot spots. Because it must have two different material of the conductor, so called the thermocouple. Different material to make the thermocouple used in different temperature range, their sensitivity is also each are not identical. The sensitivity of thermocouple refers to add 1 ℃hot spot temperature changes, the output variation of potential difference. For most of the metal material support thermocouple, this value about between 5 ~ 40 microvolt / ℃.As a result of the thermocouple temperature sensor sensitivity has nothing to do with the thickness of material, use very fine material also can make the temperature sensor. Also due to the production of thermocouple metal materials have good ductility, the slight temperature measuring element has high response speed, can measure the process of rapid change.Its advantages are:(1)high precision measurement. Because of thermocouple direct contact with the object being measured, not affected by intermediate medium.(2)the measurement range. Commonly used thermocouple from 1600 ℃to 50 ℃ ~ + sustainable measurement, some special thermocouple minimum measurable to - 269 ℃ (e.g., gold iron nickel chrome), the highest measurable to + 2800 ℃ (such as tungsten rhenium).(3) simple structure, easy to use. Thermocouple is usually composed of two different kinds of metal wire, but is not limited by the size and the beginning of, outside has protective casing, so very convenient to use. The thermocouple type and structure of the form.2. The thermocouple type and structure formation(1)the types of thermocoupleThe commonly used thermocouple could be divided into two types: standard thermocouple and non-standard thermocouple. Standard thermocouple refers to the national standard specifies its thermoelectric potential and the relationship between temperature, permissible error, and a unified standard score table of thermocouple, it has with matching display instrument to choose from. Rather than a standard thermocouple or on the order of magnitude less than the range to use standardized thermocouple, in general, there is no uniform standard, it is mainly used for measurement of some special occasions.Standardized thermocouple is our country from January 1, 1988, thermocouple and thermal resistance of all production according to IEC international standard, and specify the S, B, E, K, R, J, T seven standardization thermocouple type thermocouple for our country unified design.(2)to ensure that the thermocouple is reliable, steady work, the structure of thermocouple requirements are as follows:①of the two thermocouple thermal electrode welding must be strong;②two hot electrode should be well insulated between each other, in case of short circuit;③compensation wires connected to the free cod of a thermocouple to convenient and reliable;④protect casing thermal electrodes should be able to make sufficient isolation and harmful medium.3.The thermocouple cold end temperature compensationDue to the thermocouple materials are generally more expensive (especiallywhen using precious metals), and the temperature measurement points are generally more far, the distance to the instrument in order to save materials, reduce cost, usually adopt the compensating conductor) (the free end of the cold junction of the thermocouple to the steady control of indoor temperature, connected to the meter terminals. It must be pointed out that the role of the thermocouple compensation wire extension hot electrode, so that only moved to the control room of the cold junction of the thermocouple instrument on the terminal, it itself does not eliminate the cold end temperature change on the influence of temperature, cannot have the compensation effect. So, still need to take some of the other correction method to compensate of the cold end temperature especially when t0 indicates influence on measuring temperature 0 ℃.Must pay attention to when using thermocouple compensating conductor model match, cannot be wrong polarity, compensation conductor should be connected to the thermocouple temperature should not exceed 100 ℃.传感器传感器（英文名称：transducer/sensor）是一种检测装置，能感受到被测量的信息，并能将感受到的信息，按一定规律变换成为电信号或其他所需形式的信息输出，以满足信息的传输、处理、存储、显示、记录和控制等要求。
传感器技术论文范文
传感器技术论文范文传感器(英文名称：transducer/sensor)是直接作用于被测量、并能按一定规律将其转化为同种或别种量值输出的器件。
这是店铺为大家整理的传感器技术论文范文，仅供参考!传感器技术论文范文篇一传感器及其概述摘要传感器(英文名称：transducer/sensor)是直接作用于被测量、并能按一定规律将其转化为同种或别种量值输出的器件。
目前，传感器转换后的信号大多是电信号，因而从狭义上讲，传感器是把外界输入的非电信号转换为电信号的装置。
【关键词】传感器种类新型1 前言传感器是测试系统的一部分，其作用类似于人类的感觉器官，也可以认为是人类感官的延伸。
人们借助传感器可以去探测那些人们无法用或不便用感官直接感知的事物，如用热电偶可以测量炽热物体的温度;用超声波换能器可以测海水深度;用红外遥感器可从高空探测地面形貌、河流状态及植被的分布等。
因此，可以说传感器是人们认识自然界事物的有力工具，是测量仪器与被测量物体之间的接口。
通常情况下，传感器处于测试装置的输入端，是测试系统的第一个环节，其性能直接影响着整个测试系统，对测试精度有很大影响。
2 传感器的分类按被测物理量的不同，可以分为位移、力、温度、流量传感器等;按工作的基础不同，可以分为机械式传感器、电气式传感器、光学式传感器、流体式传感器等;按信号变换特征可以分为物性型传感器和结构型传感器;根据敏感元件与被测对象直接的能量关系，可以分为能量转换型传感器与能量控制型传感器。
3 常见传感器介绍3.1 电阻应变式传感器电阻应变式传感器又叫电阻应变计，其敏感元件是电阻应变。
应变片是在用苯酚，环氧树脂等绝缘材料浸泡过的玻璃基板上，粘贴直径为0.025mm左右的金属丝或金属箔制成。
敏感元件也叫敏感栅。
其具有体积小、动态响应快、测量精度高、使用简单等优点。
在航空、机械、建筑等各行业获得了广泛应用。
电阻应变片的工作原理是基于金属的应变效应，即金属导体在外力作用下产生机械形变，其电阻值随机械变形的变化而变化。
传感器中英文介绍
. sensorssensors(English name: transducer/sensor) is a kind of detection device, can feel the measured information, and will feel information transformation according to certain rule become electrical signal output, or other form of information needed to satisfy the information transmission, processing, storage, display, record and control requirements.Sensor's features include: miniaturization, digital, intelligent, multi-functional, systematic and network. It is the first step of automatic detection and automatic control. The existence and development of the sensor, let objects have sensory, such as touch, taste and smell let objects become live up slowly. Usually according to its basic cognitive functions are divided into temperature sensor, light sensor, gas sensor, force sensor, magnetic sensor, moisture sensor, acoustic sensor, radiation sensitive element, color sensor and sensor etc. 10 major categories.temperature transducerTemperature sensors (temperature transducer) refers to can feel temperature translates into usable output signal of the sensor. The temperature sensor is the core part of the temperature measuring instrument, wide variety. According to measuring methods could be divided into two types: contact and non-contact, according to the sensor material and electronic component features divided into two categories, thermal resistance and thermocouple.1 principle of thermocoupleThermocouple is composed of two different materials of metal wire, the welded together at the end. To measure the heating part of the environment temperature, can accurately know the temperature of the hot spots. Because it must have two different material of the conductor, so called the thermocouple. Different material to make the thermocouple used in different temperature range, their sensitivity is also each are not identical. The sensitivity of thermocouple refers to add 1 ℃hot spot temperature changes, the output variation of potential difference. For most of the metal material support thermocouple, this value about between 5 ~ 40 microvolt / ℃.As a result of the thermocouple temperature sensor sensitivity has nothing to do with the thickness of material, use very fine material also can make the temperature sensor. Also due to the production of thermocouple metal materials have good ductility, the slight temperature measuring element has high response speed, can measure the process of rapid change.Its advantages are:(1)high precision measurement. Because of thermocouple direct contact with the object being measured, not affected by intermediate medium.(2)the measurement range. Commonly used thermocouple from 1600 ℃to 50 ℃ ~ + sustainable measurement, some special thermocouple minimum measurable to - 269 ℃ (e.g., gold iron nickel chrome), the highest measurable to + 2800 ℃ (such as tungsten rhenium).(3) simple structure, easy to use. Thermocouple is usually composed of two different kinds of metal wire, but is not limited by the size and the beginning of, outside has protective casing, so very convenient to use. The thermocouple type and structure of the form.2. The thermocouple type and structure formation(1)the types of thermocoupleThe commonly used thermocouple could be divided into two types: standard thermocouple and non-standard thermocouple. Standard thermocouple refers to the national standard specifies its thermoelectric potential and the relationship between temperature, permissible error, and a unified standard score table of thermocouple, it has with matching display instrument to choose from. Rather than a standard thermocouple or on the order of magnitude less than the range to use standardized thermocouple, in general, there is no uniform standard, it is mainly used for measurement of some special occasions.Standardized thermocouple is our country from January 1, 1988, thermocouple and thermal resistance of all production according to IEC international standard, and specify the S, B, E, K, R, J, T seven standardization thermocouple type thermocouple for our country unified design.(2)to ensure that the thermocouple is reliable, steady work, the structure of thermocouple requirements are as follows:①of the two thermocouple thermal electrode welding must be strong;②two hot electrode should be well insulated between each other, in case of short circuit;③compensation wires connected to the free cod of a thermocouple to convenient and reliable;④protect casing thermal electrodes should be able to make sufficient isolation and harmful medium.3.The thermocouple cold end temperature compensationDue to the thermocouple materials are generally more expensive (especiallywhen using precious metals), and the temperature measurement points are generally more far, the distance to the instrument in order to save materials, reduce cost, usually adopt the compensating conductor) (the free end of the cold junction of the thermocouple to the steady control of indoor temperature, connected to the meter terminals. It must be pointed out that the role of the thermocouple compensation wire extension hot electrode, so that only moved to the control room of the cold junction of the thermocouple instrument on the terminal, it itself does not eliminate the cold end temperature change on the influence of temperature, cannot have the compensation effect. So, still need to take some of the other correction method to compensate of the cold end temperature especially when t0 indicates influence on measuring temperature 0 ℃.Must pay attention to when using thermocouple compensating conductor model match, cannot be wrong polarity, compensation conductor should be connected to the thermocouple temperature should not exceed 100 ℃.传感器传感器（英文名称：transducer/sensor）是一种检测装置，能感受到被测量的信息，并能将感受到的信息，按一定规律变换成为电信号或其他所需形式的信息输出，以满足信息的传输、处理、存储、显示、记录和控制等要求。
传感器英文课件第1章-basic knowledge
Transducers, Sensors, and Actuators
Transducer: converts a signal from one physical form to a corresponding signal having a different physical form “energy converter” (mechanical, thermal, magnetic, electric, chemical, and radiation) Sensor: offering an electric output A sensor may not be a transducer. modifier Input transducers (physical signal/electric signal) are termed sensors, or detectors for radiation, output transducers (electric signal/display or actuation) are termed actuators or effectors.
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1.4 Static aracteristics of Measurement Systems
Accuracy, Precision, and Sensitivity
Accuracy is the quality that characterizes the capacity of a measuring instrument for giving results close to the true value of the measured quantity. Sensor accuracy is determined through static calibration. It consists of keeping constant all sensor inputs, except the one to be studied. Error: Any discrepancy between the true value for the measured quantity and the instrument reading. Absolute error: the difference between measurement result and the true value.
传感器中英文演讲PPT
Working principle
• Light sensors can converts light signals into electrical signals with photosensitive element sensor , its sensitive wavelengths is close to the visible light wavelength, incln, security, security alarm, and energy saving and so on.
back
Pressure sensitive, temperature ,fluid sensor,sense of touch
Now ,let’s have a realization on the different
senses of machine.现在,让我们有一个感官的不
同机器上实现。
chemical sensor化学 传感器
Photosensitive sensor 光敏传感器
Acoustic sensors 声学传感器
optical signal changes（光信号变化）.
Application
• Photosensitive sensor is mainly used in
solar energy lawn lamp(太阳能草坪 灯), small optical night lights（光学小 夜灯）, camera, monitors [‘mɑnətɚ],
electric toys, electric switches, antitheft wallet, electric music box, music birthday candle, music cup, the body
传感器英文介绍作文
传感器英文介绍作文Introduction to Sensors。
Sensors are devices that are used to detect, measure, and respond to changes in the environment. They are used in a wide range of applications, from monitoring the temperature of a room to measuring the speed of a car. Sensors can be found in everyday devices such as smartphones, cars, and home appliances.Types of Sensors。
There are many different types of sensors, each designed to measure a specific parameter. Some common types of sensors include:1. Temperature sensors These sensors measure the temperature of a given environment. They are commonly used in thermostats, refrigerators, and ovens.2. Pressure sensors These sensors measure the pressure of a given environment. They are commonly used in car engines, HVAC systems, and industrial machinery.3. Light sensors These sensors detect the amount of light in a given environment. They are commonly used in cameras, smartphones, and security systems.4. Motion sensors These sensors detect motion in a given environment. They are commonly used in security systems, automatic doors, and gaming consoles.5. Proximity sensors These sensors detect the presence of objects in a given environment. They are commonly used in smartphones, cars, and industrial machinery.Applications of Sensors。
光纤传感器概述(英文)
Overview of Fiber Optic SensorsOver the past twenty years two major product revolutions have taken place due to the growth of the optoelectronics and fiber optic communications industries. The optoelectronics industry has brought about such products as compact disc players, laser printers, bar code scanners and laser pointers. The fiber optic communication industry has literally revolutionized the telecommunication industry by providing higher performance, more reliable telecommunication links with ever decreasing bandwidth cost. This revolution is bringing about the benefits of high volume production to component users and a true information superhighway built of glass.In parallel with these developments fiber optic sensor [1-6] technology has been a major user of technology associated with the optoelectronic and fiber optic communication industry. Many of the components associated with these industries were often developed for fiber optic sensor applications. Fiber optic sensor technology in turn has often been driven by the development and subsequent mass production of components to support these industries. As component prices have fallen and quality improvements have been made, the ability of fiber optic sensors to displace traditional sensors for rotation, acceleration, electric and magnetic field measurement, temperature, pressure, acoustics, vibration, linear and angular position, strain, humidity, viscosity, chemical measurements and a host of other sensor applications, has been enhanced. In the early days of fiber optic sensor technology most commercially successful fiber optic sensors were squarely targeted at markets where existing sensor technology was marginal or in many cases nonexistent. The inherent advantages of fiber optic sensors which include their ability to be lightweight, of very small size, passive, low power, resistant to electromagnetic interference, high sensitivity, wide bandwidth and environmental ruggedness were heavily used to offset their major disadvantages of high cost and unfamiliarity to the end user.The situation is changing. Laser diodes that cost $3000 in 1979 with lifetimes measured in hours now sell for a few dollars in small quantities, have reliability of tens of thousands of hours and are used widely in compact disc players, laser printers, laser pointers and bar code readers. Single mode optical fiber that cost $20/m in 1979 now costs less than $0.10/m with vastly improved optical and mechanical properties. Integrated optical devices that were not available in usable form at that time are now commonly used to support production models of fiber optic gyros. Also, they could drop dramatically in price in the future while offering ever more sophisticated optical circuits. As these trends continue, the opportunities for fiber optic sensor designers to produce competitive products will increase and the technology can be expected to assume an ever more prominent position in the sensor marketplace. In the following sections the basic types of fiber optic sensors that are being developed will be briefly reviewed followed by a discussion of how these sensors are and will be applied.Basic Concepts and Intensity Based Fiber Optic SensorsFiber optic sensors are often loosely grouped into two basic classes referred to as extrinsic or hybrid fiber optic sensors, and intrinsic or all fiber sensors. Figure 1 illustrates the case of an extrinsic or hybrid fiber optic sensor.Light ModulatorEnvironmental SignalFigure 1. Extrinsic fiber optic sensors consist of optical fibers that lead up to and out of a "black box" that modulates the light beam passing through it in response to an environmental effect.In this case an optical fiber leads up to a "black box" which impresses information onto the light beam in response to an environmental effect. The information could be impressed in terms of intensity, phase, frequency, polarization, spectral content or other methods. An optical fiber then carries the light with the environmentally impressed information back to an optical and/or electronic processor. In some cases the input optical fiber also acts as the output fiber. The intrinsic or all fiber sensor shown in Figure 2 uses an optical fiber to carry the light beam and the environmental effect impresses information onto the light beam while it is in the fiber. Each of these classes of fibers in turn has many subclasses with, in some cases sub subclasses (1) that consist of large numbers of fiber sensors.Figure 2. Intrinsic fiber optic sensors rely on the light beam propagating through the optical fiber being modulated by the environmental effect either directly or through environmentally induced optical path length changes in the fiber itself.In some respects the simplest type of fiber optic sensor is the hybrid type that is based on intensity modulation [7-8]. Figure 3 shows a simple closure or vibration sensor that consist of two optical fibers that are held in close proximity to each other. Light is injected into one of the optical fibers and when it exits the light expands into a cone oflight whose angle depends on the difference between the index of refraction of the core and cladding of the optical fiber. The amount of light captured by the second optical fiber depends on its acceptance angle and the distance d between the optical fibers. When the distance d is modulated, it in turn results in an intensity modulation of the light captured.dFigure 3. Closure and vibration fiber optic sensors based on numerical aperture can be used to support door closure indicators and measure levels of vibration in machinery.A variation on this type of sensor is shown in Figure 4. Here a mirror is used that is flexibly mounted to respond to an external effect such as pressure. As the mirror position shifts the effective separation between the optical fibers shift with a resultant intensity modulation. These types of sensors are useful for such applications as door closures where a reflective strip, in combination with an optical fiber acting to input and catch the output reflected light, can be used.Input LightCollectionFibersFigure 5. Fiber optic translation sensor based on numerical aperture uses the ratio of the output on the detectors to determine the position of the input fiber.Several companies have developed rotary and linear fiber optic position sensors to support applications such as fly-by-light [9]. These sensors attempt to eliminate electromagnetic interference susceptibility to improve safety, and to reduce shielding needs to reduce weight. Figure 6 shows a rotary position sensor [10] that consists of a code plate with variable reflectance patches placed so that each position has a unique code. A series of optical fibers are used to determine the presence or absence of a patch.VariableReflectanceShaftFigure 6. Fiber optic rotary position sensor based on reflectance used to measure rotational position of the shaft via the amount of light reflected from dark and light patches.An example of a linear position sensor using wavelength division multiplexing [11] is illustrated by Figure 7. Here a broadband light source which might be a light emitting diode is used to couple light into the system. A single optical fiber is used to carry the light beam up to a wavelength division multiplexing (WDM) element that splits the light into separate fibers that are used to interrogate the encoder card and determine linear position. The boxes on the card of Figure 7 represent highly reflective patches while the rest of the card has low reflectance. The reflected signals are then recombined and separated out by a second wavelength division multiplexing element so that each interrogating fiber signal is read out by a separate detector.λ1 λ2λ3Figure 7. Linear position sensor using wavelength division multiplexing decodes position by measuring the presence or absence of reflective patch at each fiber position as the card slides by via independent wavelength separated detectors.A second common method of interrogating a position sensor using a single optical fiber is to use time division multiplexing methods [12]. In Figure 8 a light source is pulsed. The light pulse then propagates down the optical fiber and is split into multiple interrogating fibers. Each of these fibers is arranged so that they have delay lines that separate the return signal from the encoder plate by a time that is longer than the pulse duration. When the returned signals are recombined onto the detector the net result is an encoded signal burst corresponding to the position of the encoded card.Figure 8. Linear position sensor using time division multiplexing measure decodes card position via a digital stream of on’s and off’s dictated by the presence or absence of a reflective patch.These sensors have been used to support tests on military and commercial aircraft that have demonstrated performance comparable to conventional electrical position sensors used for rudder, flap and throttle position [9]. The principal advantages of the fiber position sensors are immunity to electromagnetic interference and overall weight savings. Another class of intensity based fiber optic sensors is based on the principle of total internal reflection. In the case of the sensor in Figure 9, light propagates down the fiber core and hits the angled end of the fiber. If the medium into which the angled end of thefiber is placed has a low enough index of refraction then virtually all the light is reflected when it hits the mirrored surface and returns via the fiber. If however the index of refraction of the medium starts to approach that of the glass some of the light propagates out of the optical fiber and is lost resulting in an intensity modulation.OutputFigure 9. Fiber sensor using critical angle properties of a fiber for pressure/index of refraction measurement via measurements of the light reflected back into the fiber.This type of sensor can be used for low resolution measurement of pressure or index of refraction changes in a liquid or gel with one to ten percent accuracy. Variations on this method have also been used to measure liquid level [13] as shown by the probe configuration of Figure 10. When the liquid level hits the reflecting prism the light leaks into the liquid greatly attenuating the signal.Figure 10. Liquid level sensor based on total internal reflection detects the presence or absence of liquid by the presence or absence of a return light signal.Confinement of a propagating light beam to the region of the fiber cores and power transfer from two closely placed fiber cores can be used to produce a series of fiber sensors based on evanescence [14-16]. Figure 11 illustrates two fiber cores that have been placed in close proximity to one another. For single mode optical fiber [17] this distance is on the order of 10 to 20 microns.Light InFigure 11. Evanescence based fiber optic sensors rely on the cross coupling of light between two closely spaced fiber optic cores. Variations in this distance due to temperature, pressure or strain offer environmental sensing capabilities.When single mode fiber is used there is considerable leakage of the propagating light beam mode beyond the core region into the cladding or medium around it. If a second fiber core is placed nearby this evanescent tail will tend to cross couple to the adjacent fiber core. The amount of cross coupling depends on a number of parameters including the wavelength of light, the relative index of refraction of the medium in which the fiber cores are placed, the distance between the cores and the interaction length. This type of fiber sensor can be used for the measurement of wavelength, spectral filtering, index of refraction and environmental effects acting on the medium surrounding the cores (temperature, pressure and strain). The difficulty with this sensor that is common to many fiber sensors is optimizing the design so that only the desired parameters are sensed. Another way that light may be lost from an optical fiber is when the bend radius of the fiber exceeds the critical angle necessary to confine the light to the core area and there is leakage into the cladding. Microbending of the fiber locally can cause this to result with resultant intensity modulation of light propagating through an optical fiber. A series of microbend based fiber sensors have been built to sense vibration, pressure and other environmental effects [18-20]. Figure 12 shows a typical layout of this type of device consisting of a light source, a section of optical fiber positioned in a microbend transducer designed to intensity modulate light in response to an environmental effect and a detector. In some cases the microbend transducer can be implemented by using special fiber cabling or optical fiber that is simply optimized to be sensitive to microbending loss.Figure 12. Microbend fiber sensors are configured so that an environmental effect results in an increase or decrease in loss through the transducer due to light loss resulting from small bends in the fiber.One last example of an intensity based sensor is the grating based device [21] shown in Figure 13. Here an input optical light beam is collimated by a lens and passes through a dual grating system. One of the gratings is fixed while the other moves. With acceleration the relative position of the gratings changes resulting in an intensity modulated signal on the output optical fiber.SpringFigure 13. Grating based fiber intensity sensors measure vibration or acceleration via a highly sensitive shutter effect.One of the limitations of this type of device is that as the gratings move from a totally transparent to a totally opaque position the relative sensitivity of the sensor changes as can be seen from Figure 14. For optimum sensitivity the gratings should be in the half open half closed position. Increasing sensitivity means finer and finer grating spacings which in turn limit dynamic range.Position of GratingFigure 14. Dynamic range limitations of the grating based sensor of Figure 13 are due to smaller grating spacing increasing sensitivity at the expense of range.To increase sensitivity without limiting dynamic range, use multiple part gratings that are offset by 90 degrees as shown in Figure 15. If two outputs are spaced in this manner the resulting outputs are in quadrature as shown in Figure 16.Figure 15. Dual grating mask with regions 90 degrees out of phase to support quadrature detection which allows grating based sensors to track through multiple lines.When one output is at optimal sensitivity the other is at its lowest sensitivity and vice versa. By using both outputs for tracking, one can scan through multiple grating lines enhancing dynamic range and avoiding signal fade out associated with positions of minimal sensitivity.Figure 16. Diagram illustrating quadrature detection method that allows one area of maximum sensitivity while the other reaches a minimum and vice versa, allowing uniform sensitivity over a wide dynamic range.Intensity based fiber optic sensors have a series of limitations imposed by variable losses in the system that are not related to the environmental effect to be measured. Potential error sources include variable losses due to connectors and splices, microbending loss,macrobending loss, and mechanical creep and misalignment of light sources and detectors.To circumvent these problems many of the successful higher performance intensity based fiber sensors employ dual wavelengths. One of the wavelengths is used to calibrate out all of the errors due to undesired intensity variations by bypassing the sensing region. An alternative approach is to use fiber optic sensors that are inherently resistant to errors induced by intensity variations. In the next section a series of spectrally based fiber sensors that have this characteristic are discussed.Spectrally Based Fiber Optic SensorsSpectrally based fiber optic sensors depend on a light beam being modulated in wavelength by an environmental effect. Examples of these types of fiber sensors include those based on blackbody radiation, absorption, fluorescence, etalons and dispersive gratings.One of the simplest of these types of sensors is the blackbody sensor of Figure 17. A blackbody cavity is placed at the end of an optical fiber. When the cavity rises intemperature it starts to glow and act as a light source.Narrow Band FilterDetectorFigure 17. Blackbody fiber optic sensors allow the measurement of temperature at a hot spot and are most effective at temperatures of higher than 300 degrees C.Detectors in combination with narrow band filters are then used to determine the profile of the blackbody curve and in turn the temperature as in Figure 18. This type of sensor has been successfully commercialized and has been used to measure temperature to within a few degrees C under intense RF fields. The performance and accuracy of this sensor is better at higher temperatures and falls off at temperatures on the order of 200 degrees C because of low signal to noise ratios. Care must be taken to insure that the hottest spot is the blackbody cavity and not on the optical fiber lead itself as this can corrupt the integrity of the signal.51015Wavelength (microns)0.20.40.6S p e c t r a l R a d i a n t E m i t t a n c e (W c m -2m i c r o n -1)Figure 18. Blackbody radiation curves provide unique signatures for each temperature.Another type of spectrally based temperature sensor is shown in Figure 19 and is based on absorption [22]. In this case a Gallium Arsenide (GaAs) sensor probe is used in combination with a broadband light source and input/output optical fibers. The absorption profile of the probe is temperature dependent and may be used to determine temperature.Figure 19. Fiber optic sensor based on variable absorption of materials such as GaAs allow the measurement of temperature and pressure.Fluorescent based fiber sensors [23-24] are being widely used for medical applications,chemical sensing and can also be used for physical parameter measurements such as temperature, viscosity and humidity. There are a number of configurations for these sensors and Figure 20 illustrates two of the most common ones. In the case of the end tip sensor, light propagates down the fiber to a probe of fluorescent material. The resultant fluorescent signal is captured by the same fiber and directed back to an output demodulator. The light sources can be pulsed and probes have been made that depend onthe time rate of decay of the light pulse.GaAsSensorProbeFigure 20. Fluorescent fiber optic sensor probe configurations can be used to support the measurement of physical parameters as well as the presence or absence of chemical species. These probes may be configured to be single ended or multipoint by using side etch techniques and attaching the fluorescent material to the fiber.In the continuous mode, parameters such as viscosity, water vapor content and degree of cure in carbon fiber reinforced epoxy and thermoplastic composite materials can be monitored.An alternative is to use the evanescent properties of the fiber and etch regions of the cladding away and refill them with fluorescent material. By sending a light pulse down the fiber and looking at the resulting fluorescence, a series of sensing regions may be time division multiplexed.It is also possible to introduce fluorescent dopants into the optical fiber itself. This approach would cause the entire optically activated fiber to fluoresce. By using time division multiplexing, various regions of the fiber could be used to make a distributed measurement along the fiber length.In many cases users of fiber sensors would like to have the fiber optic analog of conventional electronic sensors. An example is the electrical strain gauge that is used widely by structural engineers. Fiber grating sensors [25-28] can be configured to have gauge lengths from 1 mm to approximately 1 cm, with sensitivity comparable to conventional strain gauges.This sensor is fabricated by "writing" a fiber grating onto the core of a Germanium doped optical fiber. This can be done in a number of ways. One method, which is illustrated by Figure 21, uses two short wavelength laser beams that are angled to form an interference pattern through the side of the optical fiber. The interference pattern consists of bright and dark bands that represent local changes in the index of refraction in the core region of the fiber. Exposure time for making these gratings varies from minutes to hours, depending on the dopant concentration in the fiber, the wavelengths used, the optical power level and the imaging optics.FiberFigure 21. Fabrication of a fiber grating sensor can be accomplished by imaging to short wavelength laser beams through the side of the optical fiber to form an interference pattern. The bright and dark fringes which are imaged on the core of the optical fiber induce an index of refraction variation resulting in a grating along the fiber core.Other methods that have been used include the use of phase masks, and interference patterns induced by short high-energy laser pulses. The short duration pulses have the potential to be used to write fiber gratings into the fiber as it is being drawn.Substantial efforts are being made by laboratories around the world to improve the manufacturability of fiber gratings as they have the potential to be used to support optical communication as well as sensing technology.Once the fiber grating has been fabricated the next major issue is how to extract information. When used as a strain sensor the fiber grating is typically attached to, or embedded in, a structure. As the fiber grating is expanded or compressed, the grating period expands or contracts, changing the gratings spectral response.For a grating operating at 1300 nm the change in wavelength is about 10-3 nm per microstrain. This type of resolution requires the use of spectral demodulation techniques that are much better than those associated with conventional spectrometers. Several demodulation methods have been suggested using fiber gratings, etalons and interferometers [29-30]. Figure 22 illustrates a system that uses a reference fiber grating. The action of the reference fiber grating is to act as a modulator filter. By using similar gratings for the reference and signal gratings and adjusting the reference grating to line up with the active grating, an accurate closed loop demodulation system may be implemented.Light SourceModulated Reference Fiber GratingFigure 22. Fiber grating demodulation systems require very high resolution spectral measurements. One way to accomplish this is to beat the spectrum of light reflected by the fiber grating against the light transmission characteristics of a reference grating.An alternative demodulation system would use fiber etalons such as those shown in Figure 23. One fiber can be mounted on a piezoelectric and the other moved relative to a second fiber end. The spacing of the fiber ends as well as their reflectivity in turn determines theFigure 23. Intrinsic fiber etalons are formed by in line reflective mirrors that can be embedded into the optical fiber. Extrinsic fiber etalons are formed by two mirrored fiber ends in a capillary tube. A fiber etalon based spectral filter or demodulator is formed by two reflective fiber ends that have a variable spacing.T r a n s m i s sio n 1.00.0Figure 24. Diagram illustrating the transmission characteristics of a fiber etalon as a function of finesse,which increases with mirror reflectivity.The fiber etalons in Figure 23 can also be used as sensors [31-33] for measuring strain as the distance between mirrors in the fiber determines their transmission characteristics. The mirrors can be fabricated directly into the fiber by cleaving the fiber, coating the end with titanium dioxide, and then resplicing. An alternative approach is to cleave the fiber ends and insert them into a capillary tube with an air gap. Both of these approaches are being investigated for applications where multiple, in line fiber sensors are required.For many applications a single point sensor is adequate. In these situations an etalon can be fabricated independently and attached to the end of the fiber. Figure 25 shows a series of etalons that have been configured to measure pressure, temperature and refractive index respectively.In the case of pressure the diaphragm has been designed to deflect. Pressure ranges of 15 to 2000 psi can be accommodated by changing the diaphragm thickness with accuracy of about 0.1 percent full scale [34]. For temperature the etalon has been formed by silicon/silicon dioxide interfaces. Temperature ranges of 70 to 500 degree K can be selected and for a range of about 100 degree K a resolution of about 0.1 degree K is achievable [34]. For refractive index of liquids a hole has been formed to allow the flow of the liquid to be measured without the diaphragm deflecting. These devices have been commercialized and are sold with instrument packages [34].Interferometeric Fiber Optic SensorsOne of the areas of greatest interest has been in the development of high performance interferometeric fiber optic sensors. Substantial efforts have been undertaken on Sagnac interferometers, ring resonators, Mach-Zehnder and Michelson interferometers as well as dual mode, polarimetric, grating and etalon based interferometers. In this section, the Sagnac, Mach-Zehnder, and Michelson interferometers are briefly reviewed.The Sagnac InterferometerThe Sagnac interferometer has been principally used to measure rotation [35-38] and is a replacement for ring laser gyros and mechanical gyros. It may also be employed to measure time varying effects such as acoustics, vibration and slowly varying phenomenon such as strain. By using multiple interferometer configurations it is possible to employ the Sagnac interferometer as a distributed sensor capable of measuring the amplitude and location of a disturbance.The single most important application of fiber optic sensors in terms of commercial value is the fiber optic gyro. It was recognized very early that the fiber optic gyro offered the prospect of an all solid-state inertial sensor with no moving parts, unprecedented reliability, and had the prospect of being very low cost.The potential of the fiber optic gyro is being realized as several manufacturers worldwide are producing them in large quantities to support automobile navigation systems, pointing and tracking of satellite antennas, inertial measurement systems for commuter aircraft and missiles, and as the backup guidance system for the Boeing 777. They are also being baselined for such future programs as the Commanche helicopter and are being developed to support long duration space flights.Other applications where fiber optic gyros are being used include mining operations, tunneling, attitude control for a radio controlled helicopter, cleaning robots, antenna pointing and tracking, and guidance for unmanned trucks and carriers.Two types of fiber optic gyros are being developed. The first type is an open loop fiber optic gyro with a dynamic range on the order of 1000 to 5000 (dynamic range is unitless), with scale factor accuracy of about 0.5 percent (this accuracy number includes non-linearity and hysterisis effects) and sensitivities that vary from less than 0.01 deg/hr to 100 deg/hr and higher [38]. These fiber gyros are generally used for low cost applications where dynamic range and linearity are not the crucial issues. The second type is the closed loop fiber optic gyro that may have a dynamic range of 106 and scale factor linearity of 10 ppm or better [38]. These types of fiber optic gyros are primarily targeted at medium to high accuracy navigation applications that have high turning rates and require high linearity and large dynamic ranges.The basic open loop fiber optic gyro is illustrated by Figure 26. A broadband light source such as a light emitting diode is used to couple light into an input/output fiber coupler. The input light beam passes through a polarizer that is used to insure the reciprocity of the counterpropagating light beams through the fiber coil. The second central coupler splits the two light beams into the fiber optic coil where they pass through a modulator that is used to generate a time varying output signal indicative of rotation. The modulator is offset from the center of the coil to impress a relative phase difference between the counterpropagating light beams. After passing through the fiber coil the two light beams recombine and pass back though the polarizer and are directed onto the output detector.LightFiber OpticCoilFigure 26. Open loop fiber optic gyro is the simplest and lowest cost rotation sensor. They are widely used in commercial applications where their dynamic range and linearity limitations are not constraining. When the fiber gyro is rotated in a clockwise direction the entire coil is displaced slightly increasing the time it takes light to traverse the fiber optic coil. (Remember that the speed of light is invariant with respect to the frame of reference, thus coil rotation increases path length when viewed from outside the fiber.) Thus the clockwise propagating light beam has to go through a slightly longer optical pathlength than the counterclockwise beam which is moving in a direction opposite to the motion of the fiber coil. The net phase difference between the two beams is proportional to the rotation rate.By including a phase modulator loop offset from the fiber coil a time difference in the arrival of the two light beams is introduced, and an optimized demodulation signal can be realized. This is shown on the right side in Figure 27. In the absence of the loop the two。
MEMS 气体传感器简介(英文版)
•lity Spectrometry
technology of gas sensor
THE CLASSIFICATION AND THE PRINCIPLE OF SENSOR
1、 Based on the gas self photoacoustic spectroscopy and optical properties of MEMS gas sensor： Photoacoustic gas sensor consists of a modulated light source , photoacoustic cell , high sensitive microphone 3 main part of the system .
and optical properties of MEMS gas sensor
• 2、Gas sensors sensitive materials based on adsorption
principle
• 3、Gas sensor for inflammable and explosive gas
THE CLASSIFICATION AND THE PRINCIPLE OF SENSOR
According to different detection theory can be
divided into:
• 1、 Based on the gas self photoacoustic spectroscopy
INTRODUCTION AND APPLICATION
Gas detection in people's production life applications is very extensive, especially in the aspects of safety in production, such as, mine operation, gas production and transportation. Gas sensor is directly related to people's life and property safety.
BENTLEY传感器产品资料
BENTLEY传感器产品资料BENTLEY传感器（英文名称：transducer/sensor）是一种检测装置，能感受到被测量的信息，并能将感受到的信息，按一定规律变换成为电信号或其他所需形式的信息输出，以满足信息的传输、处理、存储、显示、记录和控制等要求。
传感器的特点包括：微型化、数字化、智能化、多功能化、系统化、网络化。
它是实现自动检测和自动控制的首要环节。
本特利传感器或开关，由一个几乎完全闭合的包含磁铁和磁极部分的磁路组成，一个软磁铁叶片转子穿过磁铁和磁极间的气隙，在叶片转子上的窗口允许磁场不受影响的穿过并到达本特利速度传感器，而没有窗口的部分则中断磁场。
美国本特利传感器本特利传感器美国本特利系列电涡流传感器这种传感器可以直接观察到各种振动、位移、转速和时间（如相位）测量的轴或靶面位移。
由于有多种端部直径和螺纹尺寸可供选择和组合，所以其测量范围小到200微英寸（用于REBAM 测量），大到1英寸（通常用于大型蒸汽轮机的差胀测量），包括适用于大多数机器测量的80米耳范围。
速度传感器和加速度传感器与电涡流传感器直接观察机器的轴不同，壳体振动传感器安装于壳体上（通常是轴承箱体），测量壳体表面的振动。
这些产品包括加速度计和速度传感器。
因此，叶片转子窗口的作用是开关磁场，使本特利效应象开关一样地打开或关闭，这就是一些汽车厂商将本特利速度传感器和其它类似电子设备称为本特利开关的原因，该组件实际上是一个开关设备，而它的关键功能部件是本特利速度传感器。
本特利速度传感器的特点包括：微型化、数字化、智能化、多功能化、系统化、网络化，它不仅促进了传统产业的改造和更新换代，而且还可能建立新型工业，从而成为21世纪新的经济增长点。
微型化是建立在微电子机械系统（MEMS）技术基础上的，已成功应用在硅器件上做成硅压力传感器。
美国BENTLEY本特利传感器原装现货啦；本特利传感器优点：1）输出信号电压幅值不受转速的影响2）频率响应高，其响应频率高达3）抗电磁波干扰能力强主要功能常将本特利传感器的功能与人类5大感觉器官相比拟：光敏传感器——视觉声敏传感器——听觉气敏传感器——嗅觉化学传感器——味觉压敏、温敏、流体传感器——触觉本特利传感器的特点包括：微型化、数字化、智能化、多功能化、系统化、网络化，它不仅促进了传统产业的改造和更新换代，而且还可能建立新型工业，从而成为21世纪新的经济增长点。
传感器的基础知识论文中英文资料对照外文翻译
中英文资料对照外文翻译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。
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Water heater
Intelligent air conditioner measures indoor temperature at any times
Temperat sens ure or
Acceleration sensor
Game control
Detect all changes in angles Through handheld device to get the object direction
We have much more opportunities to learn and study sensor to make technology progress and make life happier.
Our goa
30%
20%
Thank you for watchin
YOU YUE
01
Sound control lamp
Decrease the electricity consumption
02
Voice recognition
Temperature sensor
To complete temperature control
Electronic thermometers
Microwave oven
Commenly sensor used in life
01 What is a sensor?
Senso rs
02 Temperature Senso
Acceleration Sens
Electronic component Physical signals
What is a senso r?
Sensor
Nowadays, Sensor are used in everyday objects
Data analysis 30%
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Acceleration sensor
Step-by-step function
Regular vibration is detected
Accelerat ion sensor
The vibration zero crossing can be detected by sensors
Calculate the number of steps
Sensors
It is widely used in…
With advances in microcontroller platform, the use of sensor have expanded beyond the traditional fields.
Data analysis 50%
Electrical signals
Same as sensations
Sound sensor
Equivalent to a microphone
Broadly used in cell phones and microphones
Sound sensor Used in normal life