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Remote sensing and IR LED lighting

Infrared LED lighting
The sensor was measured by the physical properties of the infrared. Infrared called infrared light, it has the reflection, refraction, scattering, interference, absorption properties. Any matter, so long as it has a certain temperature (more high than above absolute zero), can the infrared radiation. Infrared sensor measurement is not in direct contact with the measured object, so there is no friction, and has high sensitivity, fast response etc.. Infrared sensor comprises an optical system, a detection element and a conversion circuit. According to the structure of optical system can be divided into transmission type and reflection type two class. The detecting element according to the working principle can be divided into thermal detection device and the photoelectric detection component. The most widely used thermal element is a thermistor. Thermistor increase in temperature. the resistance to change, through the conversion into electrical signal output. Photodetector element commonly used is photosensitive element, usually made of lead sulfide, lead selenide, indium arsenide, arsenic, antimony, mercury cadmium telluride ternary alloys, germanium and silicon doped with other materials.Infrared sensors are commonly used in the non-contact temperature measurement, gas component analysis and nondestructive testing, is widely used in medical, military, space technology and environmental engineering. Such as the use of thermography infrared sensor distance measuring surface temperature of human body, can be found the temperature abnormal locations, timely diagnosis and treatment of diseases (see thermal imager); to monitor the earth clouds using infrared sensors on a satellite weather forecast, can realize large range weather forecast; using infrared sensor can detect the overheat condition when plane running engine。The human eye can see the visible light wavelength from long to short arrangement, followed by red, orange, yellow, green, cyan, blue, purple. The red light in the wavelength range of 0.62 to 0.76μm。 violet wavelength range of 0.38 ~ 0.46μm。 more short than Violet light wavelength is ultraviolet . To broadly speaking more long than red light wavelength is infrared. the sensor components can be a physical or chemical change amount to facilitate use of the electrical signal. infrared sensors is one of them. With the development of modern science and technology, the application of the infrared sensor has been very widely, with some examples below, briefly introduce the application of the infrared sensor. The working principle and characteristics of electric application and infrared sensor is a passive pyroelectric infrared probe of the human body heat released: the general human have a constant body temperature, generally at 37 degrees, so it will send a specific wavelength of 10UM infrared,the Fresnel will detecting and gather source that human body infrared emission around 10UM . Infrared sensors are usually used in pyroelectric element,
this element will be break balance of electric charge when the infrared radiation temperature changes, outward release charge, to generate an alarm signal.

1) the probe to detect human body radiation as the goal. So the pyroelectric element is very sensitive to the wavelength of the infrared radiation of about 10UM.

2) To only sensitive to infrared radiation of the human body, in the face of it and usually covered with Finil filter specia, so that the interference environment controlled by a significant role.

3) passive infrared detector, the sensor includes two mutually connected in series or parallel to the pyroelectric element. And made two electric polarization in opposite directions, environmental background radiation almost has the same effect on two pyroelectric element, make its produce pyroelectric effects offset each other, so no detector signal output.

4) once one intrusion detection area, human infrared radiation through partial mirror focusing, and the pyroelectric element is received, but two pyroelectric element received different heat, pyroelectric different, not offset by the signal processing and alarm.remote sensing as a large scope, high accuracy, quick access to information technology, will get more applications in the future technology development . Visible, sensors play a more and more important role in the field of science and technology, industrial and agricultural production and daily life. infrared sensors. As a part of them also will get larger development.

Infrared LED forInfrared LED for night vision monitoring

With more wide demand for night vision monitoring and security video surveillance system in engineering, infrared cameras have entered the mainstream market, camera sales grow with each passing day, problems in the application of infrared night vision technology is gradually exposed. In this paper, the matters needing attention in technical problems of infrared camera and selection are discussed.Buy LED infrared light source Infrared projection LED IR camera is like a flashlight, when the projection angle is small, the projection distance is far, but the monitoring range is smaller, vice versa. In most people’s mind, will think that the amount of LED infrared light determines the IR camera is good or bad, but in fact, this view is not very accurate. At present, the market of LED infrared lamp infrared camera roughly divide into external or built-in two kinds of design methods, power size will affect the detection distance of camera’s built-in LED lights, such as small space, so the monitoring distance is short. Now we will be pointed out that in fact, power of infrared LED lamp is directly influence the infrared camera irradiation distance.

At the same time, in order to achieve the best effect, the match between the LED lamp assembly design, the LED lamps and the lens is also very important. you want to enhance Virtual function of the IR camera,
First of all have to choose LED infrared light, only the high power, low current will not be overheated;
Secondly to select better LED aluminum substrate to draw heat dissipation, will not produce heat dissipation result is not good, waterproof fan fog and dust and other issues with the normal glass fiber substrate;
Third is to prevent exposure problem of infrared surveillance cameras, must solve LED infrared light reflection situation fundamentally, can add the metal partition isolation between the LED lamp and the lens, to prevent interference with the LED light;
in addition, in order to prevent fogging, also for IR camera waterproof problem is to focus on the problem of strengthening;
Finally, usually the infrared camera in the day’s focus is normal, but at night are often not normal focus, it must improve the lens depending on internal ED glass technology.

How to decrease the infrared lamp irradiation distance bring power attenuation, and prolong the service life of the infrared monitoring products, is also an important topic. We can by following these methods, in order to achieve this goal: the selection of high quality infrared led light; made of metal thin film reflective technology; adopts high efficiency optical lens (5% higher than ordinary glass light transmittance); keep constant current and constant voltage source circuit design, to ensure that the work in the current state of stability; Adapt LED circuit protection system; infrared lamps each power alone, avoid current vicious circle, failure even single lamp damage will not cause the entire lamp system; can also use multiple design to ensure that the infrared single life etc..

Analysis and application of LED infrared light source

Infrared remote control with IR LED, because the infrared light emitted by the LED is not entirely the infrared light, also contains part of the visible light (red) components, so the naked eye can see little lighting. To use the remote LED, the general emission angle is 30 degrees, even if a user is not completely aligned to the target, but also can operate effectively.

When no external infrared interference, remote control distance can reach 5 meters or more,
But there are have infrared in natural light。in generally the , the distance of the remote control within 3 meters。 Of course, enhance the transmit power of remote controller can improve the remote control distance. In theory, the transmit power increased by 100%, the distance of the remote control lifting 40%.Also with the infrared LED for monitoring camera, personally think that the most used is similar and remote control products. The sensitive range camera comprises the infrared region; therefore the use of infrared LED lighting, can let the camera to obtain the clear image. The effective distance of single LED lighting is generally not more than 2 meters, and at that distance, brightness is already very low. So the general monitoring using a plurality of LED side by side, LED amount is more, effective range farther, the approximate relationship also follow the 100%-40%. Now many LED companies have launched the infrared high power LED, power from 1W to 5W range. In General 1W infrared LED can meet the ordinary camera in the 5 metre distance lighting requirements. High power infrared LED mainly uses, in addition to use in monitoring occasions, also used in the field of military and civil situations such as search.

Infrared LED for a wire bonder

Product application: laser marking device (infrared marking device, laser marking device, infrared scriber) can be widely applied to the band saw machine, monolithic vertical sawing machine, multi piece vertical sawing machine, sawing edges, sliding table saw, sawing machine, V slot machine, shearing machine, sanding machine and so on many kinds of woodworking machinery.
Product features:
Characteristic: generation clear The red light, products applicable to all kinds of woodworking sawing machine processing, it’s intuitive and practical small volume can play the role of auxiliary marking and positioning, improve the accuracy of sawing wood, and greatly improve the work efficiency. The supporting bracket and a power supply, the use of simple and convenient. The characteristics of the IR LED used LEDlightmake.inc of semiconductor laser diode, a built-in circuit board by improved, particularly suitable for harsh working environment, can effectively guarantee the stability and the service life of the product.
Other Characteristics: positioning the modern laser technology and traditional positioning methods compared has irreplaceable advantage

A. The traditional positioning process complex; laser using simple

B. The traditional positioning fuzzy draw severe consumption in production process; laser effect is clear and accurate positioning..

C.The traditional positioning of production technology get behind, time-consuming, labor cost is high; the laser positioning technology is advanced, cost saving.

D. has the advantages of convenient installation and can make the use more convenient disassembly and simple .

E. product spot clear, good alignment, the volume is small, the industrial applicability, in the calibration of industrial and process of unemployed and positioning, replaced the ruler, a triangular plate, block and other equipment. And can help you need both hands work in local work in mechanical guide or cannot be used in. You can adjust brightness, suitable for the surface of the material and the work location of ambient light. The effective protection of the human eye with work.

F. This product line clear, compact, easy to install, simple and convenient to use. From the fundamental solution to the main problems of traditional infrared laser marking device such as short service life and low light intensity. Core used Ledlightmake.inc of semiconductor laser diode laser marking device pipe, a built-in circuit board by improved, has higher anti-interference ability, high stability and suppress the inrush current and the slow start and other characteristics, especially suitable for the bad working environment, can effectively ensure the stability of product and service life of product .

Lighting of infrared LED and microwave radar

To compare the Lighting of infrared LED and microwave radar
Lighting of infrared LED    Microwave radar

Induction way      Body infrared            Microwave radar
Induction range   Radius as 6~8meters Radius as 10~14meters
Temperature affect  High Temperature detection     NO
sensitivity will decreased
Sensitivity degree  High                         Most High
Power               0.1W                         0.3W

Firstly: what is infrared LED lamp

Infrared induction, an accurate express is passive infrared sensor,
is detection about 10uM infrared to work by the infrared probe passive detection。 The car (or people) emission around 10uM infrared to infrared inductive source by Finel filter after enhancement, infrared sensors commonly used source of pyroelectric element,
the element will be lose charge balance when receiving temperature is changes the element to the infrared radiation temperature on the receiving changes will lose charge balance, outward release charge, following circuit can generate alarm signal detected after treatment. Phenanthrene Er filter mud according to performance requirements are different, with different focal length (distance induction)

Secondly: the factors of influencing infrared LED lamp induction distance:
*the market most of the infrared induction LED, adopted two sensitive element design, induction angle is 120 degrees, the window is small, phenanthrene Er filter mud focal length (distance induction) small, therefore the induction distance near. The new technology adopts four sensitive element design, induction angle is 150 degrees, with large windows, so the induction distance.*infrared pyroelectric sensor on the vehicle (body) sensitive degree
has a very bag relationship with motion direction of people。Infrared pyroelectric sensor is not sensitive to the radial movement reaction, and for the transverse direction (i.e., perpendicular direction) movement were the most sensitive; therefore the infrared induction LED, when installing to try and lane parallel, lamp mounting angle adjustments, as far as possible need to probe direction oriented induction area, so the induction distance. Note: the parameters in the 8 meters to do the tangential
Thirdly: The working principle of microwave radar sensor:Using the Doppler principle to make the electromagnetic wave。any wave with reflection properties, when a certain frequency of the wave barrier encountered, there will be a part of the wave is reflected back, if the barrier is stationary, the reflected wave the wavelength is constant, if the barrier is an active object to the direction of movement away from the source, the wavelength of the reflected wave is more shorter than the wavelength of the wave source, if
the barrier is to the direction of movement away from the
wave source, the wavelength of the reflected wave than the wavelength of the long wave source, wavelength change, it means that the frequency change. Microwave induced by changes in the reflected wave is precisely aware of moving objects approaching or away, and output an electrical signal base this change of Microwave。 direction in forward direction of movement.Infrared lamp hanging height or less than 2.5 meters, the induction zone is 8 meters in diameter (radius as 4meters) around the ellipse.
*The lens or induction window is not covered with ash, dust can affect the sensitivity and sensing range, careful lens removal and installation, can static cloth to wipe The lens;
*when the environment temperature close to the temperature of the human body, the detection sensitivity will decreased significantly, in sometimes has resulting in short-term failure, commonly known as the temperature drift, the induction lamp adapted temperature drift suppression design, can overcome this problem

Fourthly: Characteristics of microwave radar sensor:

* The probe to detect the activity of a person or object as the goal,
as long as there have move people or object in the control range of microwave inside, can sensitively induction trigger.
* sensor through transmitting and received by the antenna signal board is the self to complete the exploration activities, microwave signal radiated from the antenna can penetrate nonmetallic materials, such as curtains, thin wall.
* sensor based on different performance requirements, can adjustable to different sensing range and sensing range.

The Basic principle and application notes of Infrared light emitting

1, light emitting diode

LED (Light Emitting Diode):

LED is a photoelectric element made of semiconductor material, element has two pin, a voltage is applied between the pin, via a tiny current can be lighting.
Namely: light emitting principle of LED is a voltage applied to the AlGaAs (AlGaAs), AlGaInP (AlInGaP) and GaInN (indium gallium nitride compound semiconductor) and so on,
Through the recombination of electrons and holes to release excess energy and luminescence, luminescence phenomena is not heating luminescence, belongs to cold light.The changes of LED by 3-5 compound semiconductor materials and device structures, and design of solid state power output in different colours, due to different materials release out of the wavelength is different, including red, orange, blue, green, yellow light, and infrared and other invisible light LED, variety.

2, The infrared light emitting diode Brief

forward bias injection current to the excitation of infrared light. Spectral power distribution of the center wavelength of 830 ~ 950nm,Infrared radiation from the high efficiency of material (often made of PN junction GaAs), the infrared light is excitation when forward bias injection current to the PN junction. The spectral power distribution of the 830 ~ 950nm central wavelength, half peak bandwidth of about 40nm or so, it is a narrowband distributed, feel the range of the ordinary CCD camera. Its biggest advantage is completely without red storm, (with 940 ~ 950nm wavelength infrared LED) or only faint red storm (red storm for visible light) and long life.Light is an electromagnetic wave, its wavelength range from several nanometers (1nm=10-9m) to 1 mm (about mm). Visible only a part of them, which we call visible light, visible light wavelength range is 380nm ~ 780nm, visible base on long to short wavelength is divided into red, orange, yellow, green, cyan, blue, purple, violet wavelength than known as the short wavelength ultraviolet light, longer than infrared light is called infrared light.

3, Recognition of infrared emitting diode

Infrared light emitting diode, similar shape to ordinary light-emitting diode, photodiode and photoelectric triode, extremely easy to cause confusion, should pay attention to distinguish. Infrared light emitting diode is used mostly colorless transparent resin package, light blue or black resin package in three forms, a colorless transparent resin packaging tube, can through the resin material for observation, if the tube core with a platter, which is an infrared light emitting diode,other LED without the platter.
4,Polar of infrared emitting diode
Usually long pin is positive, the other foot is negative. If unable to recognize from the pin length (for example has been cut short pin), can be determined by measuring the positive and negative resistance. Digital multimeter, is smaller than the measured forward resistance, the red measured pen is positive. (If the Analog Multimeter contrary, it has a relationship with the meter internal battery polarity)
Added: usually by measuring the infrared light-emitting diode negative resistance can also speculate the quality of IR LED. If the measured forward resistance values close to zero, it should be scrapped. If the reverse resistance only a few thousand ohms, or even close to zero, the IR LED will undoubtedly is bad; reverse resistance has greater the resistance, indicating that the leakage current is smaller, more good quality.

5, product characteristics
Infrared light emitting (IR LED) and transistor integrated circuit matching. Small volume, light weight, strong shock resistance, high reliability structure.
6, infrared emitting diode applications

The signal source is suitable for all kinds of photoelectric detector. Application of automatic control instrument for all kinds of hotoelectric conversion, sensor etc..According to the driving mode, can obtain stable pulse light, slow light, commonly used in remote control, alarm, wireless communication etc..

7, Application notes of infrared emitting diode:

Infrared light emitting diode should be kept clean and in good condition, especially in the front part of its spherical launch both can not exist like dirty dirt contaminants, more not by friction damage, otherwise, the infrared light emitted from the tube core will produce a reflection and scattering phenomenon, directly affect the infrared communication.

Other Application notes please refer to (Application Notes———-infrared light-emitting(IR LED))

Application Notes———-infrared light-emitting(IR LED)

Application of infrared light emitting diode(IR LED) should pay attention to matters: infrared light-emitting diode should be kept clean, good condition, especially in the front part of its spherical launch both can not exist like dirty dirt contaminants, but not damaged by friction, otherwise, the infrared light emitted from the tube core will produce a reflection and scattering phenomenon, affect the infrared communication directly.

Tools / materials

Infrared light-emitting diodes

Step / methods

1 Infrared light-emitting diodes must not exceed the limits of the parameters in the course of their work, and therefore the selection should be noted that when the substitution model and parameters of the original IR LED, can not easily replace. Further, can not be change of infrared light-emitting diode current limiting resistor.

2 Because of the range of infrared wavelengths very wide, so the infrared light-emitting diodes and infrared receiver diode must be paired, otherwise it will affect the sensitivity of the remote control, and even cause loss of control. Therefore, must be attention to the emission wavelength infrared signal parameters when substitution selection.

3 infrared LED packaging materials with Lower hardness and its high temperature performance is worse, to avoid damage to joints should be welding temperature is not too high, not too long time more, preferably with metal tweezers sandwiching the root pin, to dispose of heat.     END
Precautions The sensitivity of infrared emission diode luminous power and a photosensitive device for packaging and angular distribution, note the use of the installation point adjustment, the replacement should be adjusted accordingly. Note that the polarity of the IR LED, the IR LED don’t be closer to the heating elements.

IR Technology of the application effect

infrared thermography
Overheating may occur in all electrical parts and hardware, Including generators, transformers, insulators, the top rod connected, disconnected, jumper, hoop joint, a fuse connection, switch, starter, contactor and other hardware. In the thermal investigation of transmission and distribution systems can help reduce the loss of production and prevent these systems failed. Electrical detection using infrared thermography, can help determine the maintenance of order, prevent unplanned blackouts, lower insurance costs, reduce losses, reduce debt, repair and maintain high performance evaluation. To control the process by using infrared imaging technology, monitoring factory equipment quality and safety is a kind of method is more practical than ever. Therefore, non-contact temperature measurement(with IR LED) has become a trend.The difference between the traditional way
Easy operation: remote detection equipment of infrared thermal imaging only and its ancillary equipment mostly belongs to the non contact type, can effectively ensure the safety of the operator. As a relatively advanced infrared detection technology, it can detect operation in the premise of not interfere with the normal operation of the equipment under, so that the preventive test of the accident into a prescient testing of the accident.Fast response time: infrared thermal imaging detection device can to the amount of equipment for detecting accurate, comprehensive, timely found various aspects in the running process of equipment problems in a short period of time, even for these specific locations of problems, nature and extent to make scientific judgment.High precision temperature measurement: infrared thermal imaging instrument with high precision can distinguish the subtle differences in temperature, and can be the device thermal image real-time display to the screen, not only for the establishment of thermal image database provides technical support, but also to achieve the integration of image acquisition, storage and analysis.

Infrared machine

Infrared thermal imager adopt the infrared detectors, optical imaging lens and the light machine scanning system (currently advanced focal plane technology is eliminating ray scanning system) accept the measured target infrared radiation energy distribution pattern reflects to the light sensitive element infrared detector, between the optical system and the infrared detector, has a scanning mechanism (without this mechanism for FPA thermal imagers) scanning for infrared thermal image of the measured object, and focusing on the unit or the light detector, by infrared radiation detector will be converted into electrical signals via amplified processed, converted or standard video signals are displayed on TV screen or monitor infrared thermography.This heat distribution field map and object surface its corresponding; essentially thermal infrared radiation measured by each part of the target object is very weak,compared with the visible image, the lack of hierarchy and three-dimensional sense, therefore,
in the actual course of action to target more effectively determine the measured infrared thermal distribution field, often using some auxiliary measures to increase the instrument’s useful features, such as image brightness, contrast control, solid standard correction, pseudo-color rendering and other technologiesThe infrared thermal imager is generally divided into scanning imaging system and non scanning imaging system. Scanning imaging system adopt unit or multiple photoconductive semiconductor or photovoltaic infrared detector, slow speed by unit detector, mainly frames response time is not fast enough, multi detector array can be made high-speed and real-time thermal imager. Thermography non scanning imaging, such as focal plane array launched in recent years staring imaging surface thermal imager, thermal imaging device belongs to a new generation, in the performance is much better than scanning thermal imager, has gradually replaced the scanning thermal imager trend . The key technology is the detector consists of a monolithic integrated ( MCU )circuits, the entire field of vision test objectives are focused on it, and the image clearer, easier to use, the instrument is very compact and lightweight, and has auto-focus image freeze, continuous zoom, point temperature, line temperature, and other moderate voice annotation image and other functions, the instrument uses a PC card, the storage capacity of up to 500 images.

the application of LED in traffic field(2)

Ciscoloration and customers, improve the efficiency of light
1, monochromatic light having a divergence angle
Monochromatic light emitted from the LED, and thus do not need to customers color film to produce red, yellow and green color signals; light emitted by the LED direction,, and a certain divergence angle, which can be used instead of the traditional lights aspheric mirrors. This feature of LED lights to solve the traditional presence of the phantom (commonly known as false display) and color film fading problems, improve the optical efficiency

2, cold light source, low energy consumption Advantages in energy saving LED light source is very obvious, one of its notable feature is the low power consumption, which in terms of lighting applications is significant.

3, good reliability, long life Lights work environment is relatively harsh, cold summer, sun and rain, and thus higher reliability requirements lamps. The average life expectancy is generally lights with incandescent bulbs is 1000h, the average life expectancy low voltage halogen bulb is 2000h, high maintenance costs arising therefrom. In actual use, there have been many LED traffic lights use the time more than five years, and no damage to the LED. There is a relatively large advantage is less than halogen bulbs, etc. are fast response time, thereby reducing the occurrence of post accident. Several problems on the LED traffic signal lamp:

1,The high power LED applications,, high power LED has the advantages of greatly reduced the number of LED, but the problem that needs solving heat dissipation and cost.
2, although the electrical parameters and electromagnetic intensity index, LED traffic signal lamp compatibility requirements gradually improved, however, optical design, LED signal lamp circuit design also needs further optimization, in order to become the mainstream of traffic signal lamp design.
3, with energy saving, environmental protection requirements increase, LED signals with the combination of solar energy will be popular, but need to solve the matching problem and traffic signal control machine.

In a word, the application of LED in the traffic signal lamp, its development is very rapid, and applications used in the transport sector is also very good market prospects have basically an alternative to traditional light sources. Although the traffic signal products on the market has been close to saturation, but because LED has the environmental protection, energy saving, long life and other advantages, the application of LED in traffic field still has very large space.

LED used in traffic lights

Currently, The high-power Led application of automotive lighting, lighting, LCD backlighting, and the old-fashioned general traffic lights to replace the time is comes. the new tri-color LED highlight traffic lights are to a wide range of application. In fact, a set of comprehensive, high quality LED traffic lights price is very expensive, but because of the important role of traffic lights in city traffic, every year a large number of traffic lights need to be updated,after all, high profit is conducive to the development of LED production design company, for the entire LED industry will produce a benign stimulation.LED for traffic lights

Transportation applications, LED products mainly include red, green, yellow signal indication, digital time display, an arrow indication. Products require high lighting during reduce the brightness to avoid glare at night. LED traffic signal light source directing light by plurality of LED, we consider multiple focus when design of the light. and the installation of the LED’s also have some requirements, if the installation inconsistency will affect the uniformity of the light-emitting surface , and therefore the design must consider how to avoid such defects, if the optical design is too simple, the distribution of light signal lamp is mainly rely on the LED perspective to insure lighting in effect. So the LED light distribution and installation requirements are more stringent, otherwise this bad phenomenon will be very obvious.LED traffic signal lamp on the light distribution also have some differences , although have the same intensity distribution requirements. The car headlights in light cut line requirements more stringent. The design as long as the vehicle headlamp is enough light to the appropriate configuration of the place, regardless of where the light is emitted by the designer can be divided into small sub-region of the lens to the light distribution area design, it must meet the use of the signal lamp any work area to observe the signal lamp light-emitting surface, signal patterns are clear and visual effects are uniform. While incandescent and halogen lamps light lights light stable, uniform, but the presence of high energy consumption, low life service time expectancy, easy to produce phantom signal display, color film easy to fade and other defects. If we can reduce the LED die light phenomenon, reducing the light fades so high brightness, low power LED applications in the lights, the lights will definitely bring about revolutionary changes in the signal lamp products.

Application of LED in traffic field mainly has following several aspects:
1, traffic signal lamp. LED signal lamp with its high brightness, high reliability, low use cost, long life and other characteristics, get the favour of city traffic management department.
2, the highway traffic guidance system. With the improvement of the standard of highway construction, LED traffic guidance system has become the standard configuration of product, market demand.
3, induced by urban road traffic, signs. With the traffic congestion in major cities is becoming more and more serious, LED display in the cities are growing rapidly in road traffic guidance.