CN209513532U - A kind of laser dust monitor that dark current automatically removes - Google Patents

A kind of laser dust monitor that dark current automatically removes Download PDF

Info

Publication number
CN209513532U
CN209513532U CN201920260055.4U CN201920260055U CN209513532U CN 209513532 U CN209513532 U CN 209513532U CN 201920260055 U CN201920260055 U CN 201920260055U CN 209513532 U CN209513532 U CN 209513532U
Authority
CN
China
Prior art keywords
circuit
output
laser
dark current
signal
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related
Application number
CN201920260055.4U
Other languages
Chinese (zh)
Inventor
恽新星
李泓
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Wuxi Institute of Commerce
Original Assignee
Wuxi Institute of Commerce
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Wuxi Institute of Commerce filed Critical Wuxi Institute of Commerce
Priority to CN201920260055.4U priority Critical patent/CN209513532U/en
Application granted granted Critical
Publication of CN209513532U publication Critical patent/CN209513532U/en
Expired - Fee Related legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Landscapes

  • Semiconductor Lasers (AREA)

Abstract

一种暗电流自动去除的激光粉尘仪,包括激光管、恒光功率驱动电路、振荡电路、PIN二极管、I‑V转换电路、电压放大电路、模拟开关、低通滤波器和信号采集处理显示电路。振荡电路产生占空比为50%的方波信号,控制恒光功率驱动电路驱动激光管周期性发射激光;同时控制模拟开关切换接收信号的极性,从而实现暗电流的自动消除。本实用新型通过暗电流自动去除电路,消除了由于工作温度、工作电压等工作条件变化所引起的暗电流变化所带来的测量误差,保证了激光粉尘仪测量的精度;也消除了长时间工作导致的光电二极管性能变化引起的暗电流变化带来的测量误差,延长了激光粉尘仪的使用寿命;使激光粉尘仪的精度更高,稳定性更好,使用寿命更长。

A laser dust meter for automatic removal of dark current, including a laser tube, a constant light power drive circuit, an oscillation circuit, a PIN diode, an I-V conversion circuit, a voltage amplification circuit, an analog switch, a low-pass filter, and a signal acquisition and processing display circuit. The oscillating circuit generates a square wave signal with a duty cycle of 50%, which controls the constant light power drive circuit to drive the laser tube to emit laser light periodically; at the same time, the analog switch is controlled to switch the polarity of the received signal, thereby realizing the automatic elimination of dark current. The utility model eliminates the measurement error caused by the change of dark current caused by the change of working conditions such as working temperature and working voltage through the dark current automatic removal circuit, and ensures the measurement accuracy of the laser dust meter; it also eliminates the need for long-time work The measurement error caused by the change of the dark current caused by the change of the performance of the photodiode prolongs the service life of the laser dust meter; the accuracy of the laser dust meter is higher, the stability is better, and the service life is longer.

Description

一种暗电流自动去除的激光粉尘仪A laser dust meter for automatic removal of dark current

技术领域technical field

本实用新型涉及粉尘监测领域,尤其涉及一种暗电流自动去除的激光粉尘仪。The utility model relates to the field of dust monitoring, in particular to a laser dust meter for automatic removal of dark current.

背景技术Background technique

粉尘是一种能长时间地以浮游方式存在于空气中的固体颗粒。粉尘会导致肺部疾病、皮肤感染、癌症等多种疾病,严重影响人们的身体健康。排出厂房外的粉尘还会污染厂区外的环境,对厂区周围的居民健康造成影响,对农、林、牧业的生产造成影响。这几年空气污染现象比较严重,粉尘的污染也是一个很重要的因素。随着人们对生产、生活环境的要求越来越高,人们也越来越重视环境保护。粉尘的监测和控制也越来越被重视。Dust is a kind of solid particles that can exist in the air in the form of floating for a long time. Dust can cause lung disease, skin infection, cancer and other diseases, seriously affecting people's health. The dust discharged outside the factory building will also pollute the environment outside the factory area, affect the health of residents around the factory area, and affect the production of agriculture, forestry, and animal husbandry. In recent years, air pollution has become more serious, and dust pollution is also a very important factor. As people's requirements for production and living environment are getting higher and higher, people are paying more and more attention to environmental protection. The monitoring and control of dust is also paid more and more attention.

粉尘检测仪就是用来检测空气中粉尘浓度的专用仪器。在实际应用中,常用的粉尘检测方法通常有三种:称重法、激光法和感应法。The dust detector is a special instrument used to detect the concentration of dust in the air. In practical applications, there are usually three commonly used dust detection methods: weighing method, laser method and induction method.

激光法通过测量激光经过包含粉尘的被测空气后的衰减或散射来测量粉尘浓度。粉尘浓度越高,衰减和散射越强烈。The laser method measures the dust concentration by measuring the attenuation or scattering of the laser light passing through the measured air containing dust. The higher the dust concentration, the stronger the attenuation and scattering.

现有的激光粉尘仪大多采用连续驱动方式,不可避免的存在暗电流随着工作温度、工作电压的波动而变化的问题。随着工作时间的增加,接收用的光电二极管性能发生变化也会带来暗电流的增加,从而导致测量结果的误差增加。Most of the existing laser dust meters adopt the continuous driving mode, and there is an inevitable problem that the dark current changes with the fluctuation of the working temperature and working voltage. As the working time increases, the performance of the receiving photodiode changes and the dark current increases, which leads to an increase in the error of the measurement result.

如何降低暗电流的影响,从而降低测量误差,延长粉尘仪使用寿命,是目前激光粉尘仪需要解决的问题之一。How to reduce the influence of dark current, so as to reduce the measurement error and prolong the service life of the dust meter, is one of the problems that the laser dust meter needs to solve at present.

发明内容Contents of the invention

本实用新型目的在于针对现有激光粉尘仪存在的缺陷,提供一种暗电流自动去除的激光粉尘仪,从而降低测量误差,延长粉尘仪使用寿命。The purpose of the utility model is to provide a laser dust meter with automatic dark current removal for the defects of the existing laser dust meter, so as to reduce measurement errors and prolong the service life of the dust meter.

本实用新型为实现上述目的,采用如下技术方案:For realizing the above object, the utility model adopts the following technical solutions:

一种暗电流自动去除的激光粉尘仪,包括激光管和用于接收所述激光管发射激光的接收装置;其特征在于:A laser dust meter for automatic removal of dark current, comprising a laser tube and a receiving device for receiving laser light emitted by the laser tube; it is characterized in that:

所述接收装置输出连接I-V转换电路,将输出电流信号转换为电压信号;The output of the receiving device is connected to an I-V conversion circuit to convert the output current signal into a voltage signal;

所述I-V转换电路输出连接电压放大电路,将输出的电压信号进行放大;The output of the I-V conversion circuit is connected to a voltage amplifier circuit to amplify the output voltage signal;

所述电压放大电路输出同时连接一个模拟开关的正输入端和负输入端;The output of the voltage amplifying circuit is simultaneously connected to a positive input terminal and a negative input terminal of an analog switch;

所述模拟开关连接一个振荡电路,通过所述振荡电路的输出控制所述模拟开关的正输入端和负输入端接通;所述模拟开关输出连接低通滤波器;The analog switch is connected to an oscillating circuit, and the positive input terminal and the negative input terminal of the analog switch are controlled to be connected through the output of the oscillating circuit; the output of the analog switch is connected to a low-pass filter;

所述低通滤波器输出连接信号采集处理显示电路;The output of the low-pass filter is connected to the signal acquisition and processing display circuit;

所述信号采集处理显示电路用于采集所述低通滤波器输出信号,输出显示粉尘浓度;The signal collection processing display circuit is used to collect the output signal of the low-pass filter, and the output shows the dust concentration;

所述振荡电路同时连接恒光功率驱动电路,通过振荡信号控制所述恒光功率驱动电路输出;The oscillating circuit is connected to the constant light power drive circuit at the same time, and the output of the constant light power drive circuit is controlled by an oscillation signal;

所述恒光功率驱动电路输出连接所述激光管,使所述激光管周期性发射激光。The output of the constant light power drive circuit is connected to the laser tube, so that the laser tube periodically emits laser light.

其进一步特征在于:所述振荡电路输出方波。It is further characterized in that: the oscillating circuit outputs a square wave.

优选的:所述方波为占空比50%的方波。Preferably: the square wave is a square wave with a duty cycle of 50%.

所述激光管为波长650nm最大功率10mW的激光二极管;所述振荡电路采用NE555集成芯片搭建;所述接收装置为S1226-44BK PIN二极管;所述模拟开关为CD4053芯片;所述低通滤波器为阻容滤波器。The laser tube is a laser diode with a wavelength of 650nm and a maximum power of 10mW; the oscillating circuit is built with an NE555 integrated chip; the receiving device is a S1226-44BK PIN diode; the analog switch is a CD4053 chip; the low-pass filter is RC filter.

本实用新型通过振荡电路输出振荡信号同时控制激光管周期性发射激光和模拟开关切换,使得暗电流和正常电流信号在低通滤波器上叠加,从而抵消了暗电流的影响。减小由于工作温度、工作电压的波动而导致暗电流变化引起的测量误差;同时减小由于长时间工作导致的接收用接收装置性能变化引起的测量误差,从而延长粉尘仪的使用寿命。The utility model outputs the oscillation signal through the oscillation circuit and simultaneously controls the laser tube to periodically emit laser light and switch the analog switch, so that the dark current and normal current signals are superimposed on the low-pass filter, thereby offsetting the influence of the dark current. Reduce the measurement error caused by dark current changes due to fluctuations in operating temperature and operating voltage; at the same time reduce the measurement error caused by the performance change of the receiving device due to long-term work, thereby prolonging the service life of the dust meter.

附图说明Description of drawings

图 1 为本实用新型原理示意图。Figure 1 is a schematic diagram of the principle of the utility model.

具体实施方式Detailed ways

如图1所示,一种暗电流自动去除的激光粉尘仪,包括激光管1和用于接收激光管1发射激光的PIN二极管23。As shown in FIG. 1 , a laser dust meter for automatic removal of dark current includes a laser tube 1 and a PIN diode 23 for receiving laser light emitted by the laser tube 1 .

PIN二极管23输出连接I-V转换电路24,将输出电流信号转换为电压信号。The output of the PIN diode 23 is connected to the I-V conversion circuit 24 to convert the output current signal into a voltage signal.

I-V转换电路24输出连接电压放大电路25,将输出的电压信号进行放大。The output of the I-V conversion circuit 24 is connected to the voltage amplifying circuit 25 to amplify the output voltage signal.

电压放大电路25输出同时连接一个模拟开关26的正输入端和负输入端。The output of the voltage amplifying circuit 25 is simultaneously connected to the positive input terminal and the negative input terminal of an analog switch 26 .

模拟开关26连接一个振荡电路22,通过振荡电路22的输出的方波信号控制模拟开关26的正输入端和负输入端接通;模拟开关26输出连接一个低通滤波器27。The analog switch 26 is connected to an oscillating circuit 22 , and the positive and negative input terminals of the analog switch 26 are controlled to be connected by the square wave signal output by the oscillating circuit 22 ; the output of the analog switch 26 is connected to a low-pass filter 27 .

低通滤波器27输出连接信号采集处理显示电路28。The output of the low-pass filter 27 is connected to a signal acquisition, processing and display circuit 28 .

信号采集处理显示电路28用于采集低通滤波器27输出信号,输出显示粉尘浓度。The signal collection, processing and display circuit 28 is used to collect the output signal of the low-pass filter 27, and the output shows the dust concentration.

振荡电路22同时连接恒光功率驱动电路21,通过方波信号控制恒光功率驱动电路21输出。The oscillating circuit 22 is connected to the constant light power drive circuit 21 at the same time, and controls the output of the constant light power drive circuit 21 through a square wave signal.

恒光功率驱动电路21输出连接激光管1,使激光管1周期性发射激光。The output of the constant optical power drive circuit 21 is connected to the laser tube 1, so that the laser tube 1 periodically emits laser light.

优选的:激光管1采用波长650nm最大功率10mW的激光二极管。振荡电路22可采用NE555集成芯片搭建。PIN二极管23采用S1226-44BK。模拟开关26可使用CD4053芯片实现。低通滤波器27可使用阻容滤波实现。方波信号为占空比50%的方波。Preferably: the laser tube 1 adopts a laser diode with a wavelength of 650nm and a maximum power of 10mW. The oscillating circuit 22 can be constructed using an NE555 integrated chip. PIN diode 23 adopts S1226-44BK. The analog switch 26 can be implemented using a CD4053 chip. The low-pass filter 27 can be implemented using resistance-capacitance filtering. The square wave signal is a square wave with a duty cycle of 50%.

本实用新型工作时,振荡电路22产生占空比为50%的方波信号,在低电平时关闭恒光功率驱动电路21,激光管1不发射激光,同时模拟开关26接通到负输出端。此时PIN二极管23未接收到光,PIN二极管23的暗电流信号经过I-V转换电路24和电压放大电路25后输出,此暗电流信号反向接入低通滤波器27。在高电平时打开恒光功率驱动电路21,激光管1发射激光,同时模拟开关26接通到正输出端。此时PIN二极管23接收散射光,PIN二极管23的正常电流信号经过I-V转换电路24和电压放大电路25后输出,此正常电流信号正向接入低通滤波器27。通过来回切换暗电流和正常电流信号在低通滤波器27上叠加,从而抵消了暗电流的影响。When the utility model is working, the oscillating circuit 22 generates a square wave signal with a duty ratio of 50%, and the constant light power drive circuit 21 is turned off at low level, the laser tube 1 does not emit laser light, and the analog switch 26 is connected to the negative output terminal at the same time. At this time, the PIN diode 23 does not receive light, and the dark current signal of the PIN diode 23 is output after passing through the I-V conversion circuit 24 and the voltage amplifying circuit 25 , and the dark current signal is reversely connected to the low-pass filter 27 . When the level is high, the constant optical power drive circuit 21 is turned on, the laser tube 1 emits laser light, and the analog switch 26 is connected to the positive output terminal at the same time. At this time, the PIN diode 23 receives the scattered light, and the normal current signal of the PIN diode 23 is output after passing through the I-V conversion circuit 24 and the voltage amplifying circuit 25 , and the normal current signal is forwardly connected to the low-pass filter 27 . The dark current and normal current signals are superimposed on the low-pass filter 27 by switching back and forth, thereby canceling the influence of the dark current.

Claims (4)

1.一种暗电流自动去除的激光粉尘仪,包括激光管和用于接收所述激光管发射激光的接收装置;其特征在于:1. A laser dust meter for automatic removal of dark current, comprising a laser tube and a receiving device for receiving said laser tube emitting laser light; it is characterized in that: 所述接收装置输出连接I-V转换电路,将输出电流信号转换为电压信号;The output of the receiving device is connected to an I-V conversion circuit to convert the output current signal into a voltage signal; 所述I-V转换电路输出连接电压放大电路,将输出的电压信号进行放大;The output of the I-V conversion circuit is connected to a voltage amplifier circuit to amplify the output voltage signal; 所述电压放大电路输出同时连接一个模拟开关的正输入端和负输入端;The output of the voltage amplifying circuit is simultaneously connected to a positive input terminal and a negative input terminal of an analog switch; 所述模拟开关连接一个振荡电路,通过所述振荡电路的输出控制所述模拟开关的正输入端和负输入端接通;所述模拟开关输出连接低通滤波器;The analog switch is connected to an oscillating circuit, and the positive input terminal and the negative input terminal of the analog switch are controlled to be connected through the output of the oscillating circuit; the output of the analog switch is connected to a low-pass filter; 所述低通滤波器输出连接信号采集处理显示电路;The output of the low-pass filter is connected to the signal acquisition and processing display circuit; 所述信号采集处理显示电路用于采集所述低通滤波器输出信号,输出显示粉尘浓度;The signal collection processing display circuit is used to collect the output signal of the low-pass filter, and the output shows the dust concentration; 所述振荡电路同时连接恒光功率驱动电路,通过振荡信号控制所述恒光功率驱动电路输出;The oscillating circuit is connected to the constant light power drive circuit at the same time, and the output of the constant light power drive circuit is controlled by an oscillation signal; 所述恒光功率驱动电路输出连接所述激光管,使所述激光管周期性发射激光。The output of the constant light power drive circuit is connected to the laser tube, so that the laser tube periodically emits laser light. 2.如权利要求1所述的暗电流自动去除的激光粉尘仪,其特征在于:所述振荡电路输出方波。2. The laser dust meter for automatic removal of dark current according to claim 1, characterized in that: the oscillation circuit outputs a square wave. 3.如权利要求2所述的暗电流自动去除的激光粉尘仪,其特征在于:所述方波为占空比50%的方波。3. The laser dust meter for automatic removal of dark current according to claim 2, wherein the square wave is a square wave with a duty cycle of 50%. 4.如权利要求1-3任一项所述的暗电流自动去除的激光粉尘仪,其特征在于:所述激光管为波长650nm最大功率10mW的激光二极管;所述振荡电路采用NE555集成芯片搭建;所述接收装置为S1226-44BK PIN二极管;所述模拟开关为CD4053芯片;所述低通滤波器为阻容滤波器。4. The laser dust meter for automatic removal of dark current according to any one of claims 1-3, characterized in that: the laser tube is a laser diode with a wavelength of 650nm and a maximum power of 10mW; the oscillation circuit is built with an NE555 integrated chip ; The receiving device is a S1226-44BK PIN diode; the analog switch is a CD4053 chip; the low-pass filter is a resistance-capacitance filter.
CN201920260055.4U 2019-03-01 2019-03-01 A kind of laser dust monitor that dark current automatically removes Expired - Fee Related CN209513532U (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201920260055.4U CN209513532U (en) 2019-03-01 2019-03-01 A kind of laser dust monitor that dark current automatically removes

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201920260055.4U CN209513532U (en) 2019-03-01 2019-03-01 A kind of laser dust monitor that dark current automatically removes

Publications (1)

Publication Number Publication Date
CN209513532U true CN209513532U (en) 2019-10-18

Family

ID=68204922

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201920260055.4U Expired - Fee Related CN209513532U (en) 2019-03-01 2019-03-01 A kind of laser dust monitor that dark current automatically removes

Country Status (1)

Country Link
CN (1) CN209513532U (en)

Similar Documents

Publication Publication Date Title
CN102445458B (en) Method for measuring stain on optical lens
CN101246112A (en) Measuring method and measuring device for suspended sediment content in water body
WO2015161748A1 (en) Measurement method for un-gated liquid turbidity measurement device based on time-correlated single photon counting
CN104596990A (en) Two-channel optical fiber method and sensor for measuring turbidity
CN104266947A (en) Aerosol particle concentration sensor and detection method thereof
CN107044890A (en) Adaptive fluorescence fiber temperature measurement device and method over long distances
CN101782408A (en) Grain flow-measuring method and device
CN103575705A (en) Turbidity meter and measuring method for turbidity of water
CN201464353U (en) An infrared moisture detector
CN209513532U (en) A kind of laser dust monitor that dark current automatically removes
CN205484803U (en) Ranging system based on photoelectric sensor
CN207300816U (en) A kind of particulate matter sensors based on pulsed laser deposition
CN201156029Y (en) A digital sensor for particle detection
CN103913503A (en) Dissolved oxygen detection device and dissolved oxygen detector
CN201504347U (en) Constant Light Source Control System of Atmospheric Visibility Meter
CN204789329U (en) Infrared turbidity detection device
CN208208052U (en) A kind of smoke sensor device and its control circuit
CN204167884U (en) Survey and protect the universal microcomputer protecting device of merger
CN217033513U (en) Infrared light silt content measuring sensor
CN203732442U (en) Turbidity measuring instrument based on microprocessor STM32F103
CN203643333U (en) a turbidity meter
CN103558267A (en) Online dust concentration detection system based on capacitor detection technology
CN202771574U (en) Integrated smoke detector
CN213812717U (en) Underground pressure alarm device
CN114894683A (en) An online automatic monitor for sediment content

Legal Events

Date Code Title Description
GR01 Patent grant
GR01 Patent grant
CF01 Termination of patent right due to non-payment of annual fee

Granted publication date: 20191018

Termination date: 20200301

CF01 Termination of patent right due to non-payment of annual fee