Research on measurement of urban C8H8 by open optical path detection system

2019 ◽  
Author(s):  
Rui Xue ◽  
Mingxuan Li ◽  
Jiatong Shi ◽  
Xiaohong Han ◽  
Han Zhang
Keyword(s):  
Detection System ◽  
Optical Path ◽  
Path Detection

scholarly journals Near-Infrared C2H2 Detection System Based on Single Optical Path Time Division Multiplexing Differential Modulation Technique and Multi-Reflection Chamber

2019 ◽  
Vol 9 (13) ◽  
pp. 2637 ◽  
Author(s):  
Biao Wang ◽  
Hongfei Lu ◽  
Chen Chen ◽  
Lei Chen ◽  
Houquan Lian ◽  
...  
Keyword(s):  
Near Infrared ◽  
Detection System ◽  
Optical Path ◽  
Integration Time ◽  
Allan Deviation ◽  
Differential Modulation ◽  
Time Division Multiplexing ◽  
Detection Range ◽  
Modulation Technique ◽  
Time Division

A time division multiplexing differential modulation technique is proposed to address the interference problem caused by the fluctuation of laser light intensity in the single optical path detection system. Simultaneously, a multi-reflection chamber is designed and manufactured to further improve the system’s precision with an optical path length of 80 m. A near-infrared C2H2 detection system was developed. The absorption peak of the acetylene (C2H2) molecule near 1520 nm was selected as the absorption line. A laser driver is developed, and a lock-in amplifier is used to extract the second harmonic (2f) signal. A good linear relationship existed between C2H2 concentration and the 2f signal, and the correlation coefficient was 0.9997. In the detection range of 10–100 ppmv, the minimum detection limit was 0.3 ppmv, and the precision was 2%. At 50 ppmv, C2H2 and continuous detection for 10 h, the data average was 50.03 ppmv, and the fluctuation was less than ±1.2%. The Allan variance method was adopted to evaluate the long-term characteristic of the system. At 1 s of integration time, the Allan deviation was 0.3 ppmv. When the integration time reached 362 s, the Allan deviation was 0.0018 ppmv, which indicates the good stability of the detection system.

The Research of the Multi-Axis Consistency Assembly Adjustment of Optical Collimator

2013 ◽  
Vol 552 ◽  
pp. 298-304
Author(s):  
Zuo Jiang Xiao ◽  
Xuan Chen ◽  
Hai Bin Zhu ◽  
Yan Qing Wang ◽  
Yang Xia ◽  
...  
Keyword(s):  
Measurement Error ◽  
Optical System ◽  
Optical Axis ◽  
Detection System ◽  
Optical Path ◽  
Equivalent Method

This paper reaches a detection system which use for detecting the three-axis consistency of optical collimator basing on equivalent method. Describing the detect principle and calculating the offset of the image of optical path caused by spectroscope via anglicizing of optical system. Meanwhile, it uses zemax to simulate the offset of optical path. After adjusting the structure of the system, the detection system is calibrated by theodolite whose accuracy is 0.5″. The experiment result shows that the measurement error of the optical axis consistency <0.05mrad.

Design of Photoelectric Detection System Used for Atmospheric Microdroplets and Modulation Transfer Function Model of Gaussian Beam

2021 ◽  
Vol 16 (7) ◽  
pp. 1098-1106
Author(s):  
Yang Ping
Keyword(s):  
Detection Limit ◽  
Transfer Function ◽  
Modulation Transfer Function ◽  
Atmospheric Corrosion ◽  
Detection System ◽  
Optical Path ◽  
Transfer Function Model ◽  
Modulation Transfer ◽  
Function Model ◽  
Photoelectric Detection

Atmospheric corrosion is an electrochemical corrosion process of metal materials in the atmospheric environment. Microdroplet phenomenon is an experimental phenomenon in the early stage of atmospheric corrosion, which is closely related to atmospheric corrosion. Photoelectric detection of microdroplet phenomenon has become a technical means to study atmospheric corrosion. A set of microdroplet photoelectric detection systems with small size, high integration, and low detection limit is designed and constructed. First, the microdroplet optical chip is designed and fabricated. The microdroplet chip with a single function is replaced by the microdroplet chip with optical microlenses, and the miRNA is detected on the photoelectric platform of the optical chip. The optical fiber is adopted to replace the traditional objective lens to excite the optical path, reduce the volume of the spatial optical path, and realize the miniaturization of the photoelectric detection system. Based on this system, the nonlinear relationship between atmospheric turbulence effect and atmospheric optical parameters is analyzed with Gaussian beams propagating in the atmosphere. In the experiment, the detection range of the photoelectric detection system is 5 nM~100 nM, and the linear correlation is 0.9958. The signals of Cy3 and Cy5 are detected by two groups of photomultiplier tube (PMT) to realize the detection of miRNA. Microlenses enhance the intensity of the photoelectric signal and reduce the detection limit. Microdroplets are used to encapsulate miRNA, reduce the amount of detection material, and solve the degradation of detection material by RNase. The modulation transfer function model of Gaussian beam is established with the assistance of the photoelectric detection system, which is suitable for the case that cannot be ignored in Kolmogorov turbulence under the action of internal/external scale.

Study on Error Factors of Magneto–Optical Current Transformer

2013 ◽  
Vol 303-306 ◽  
pp. 853-858
Author(s):  
Jin Wei Li ◽  
Yi Ning Zhang ◽  
Hao Chen ◽  
Jue He
Keyword(s):  
Detection Method ◽  
Optical Axis ◽  
Current Transformer ◽  
Optical Path ◽  
Angle Error ◽  
Operating Wavelength ◽  
Path Detection

The working principles of MOCT(Magneto–Optical Current Transformer) based on improved dual optical path detection method is studied. The MOCT’s output could be influenced by both the fluctuation of operating wavelength and the error of intersecting angle of optical axis between polarizer and analyzer . Based on IEC 60044-8 standard, the scope of the photosource wavelength and angle error of photic axis are obtained. The results would be useful for researchers and designers working in the MOCT area.

Three-dimensional dynamic non-contact attitude detection system based on optical path deflection technology

2021 ◽  
Author(s):  
Zhihang Zhang ◽  
Shuai Zhao ◽  
Chao Ma ◽  
Dengwei Zhang ◽  
Xiaowu Shu ◽  
...  
Keyword(s):  
Detection System ◽  
Three Dimensional ◽  
Optical Path ◽  
Attitude Detection
Sign in / Sign up

Export Citation Format

Share Document