|
|
|
|
|
|
| Research on the Relationship Between Modulation Depth and Center of High Order Harmonic in TDLAS Wavelength Modulation Method |
| CHEN Hao1, 2, JU Yu3，HAN Li1 |
1. Institute of Electrical Engineering, Chinese Academy of Sciences, Beijing 100190, China
2. University of Chinese Academy of Sciences, Beijing 100049, China
3. Beijing Aerospace Yilian Science and Technology Development Company, Beijing 100176, China |
|
|
|
|
Abstract Tunable Semiconductor Laser Spectroscopy (TDLAS) has been a rapidly developing spectral detection technology in recent years. Compared with other spectral detection technologies, TDLAS has the advantages of high sensitivity, high resolution, real-time monitoring, good portability and miniaturization, and has been widely used in the fields of industrial environmental protection, medical detection, meteorological monitoring and so on. The harmonic signal in the TDLAS wavelength modulation method is susceptible to air pressure. It is found that the influence of air pressure is the influence of modulation depth on the harmonic signal. Based on the principle of the harmonic method in TDLAS technology, the relationship between each harmonic and modulation depth is studied. The modulation depth of the current air pressure environment is calculated by calculating the center amplitude ratio of the fourth harmonic to the second harmonic. To adjust the amplitude of the modulation frequency so that the modulation depth is close to the optimal modulation depth value of each subharmonic, and the signal-to-noise ratio of the harmonic signal is optimal to improve the detection accuracy. The second and fourth harmonic signals under 10.2~177.9 kPa pressure were extracted by the TDLAS water vapor detection system. The simulation and experimental analysis were carried out. The simulation results show that the maximum relative error of the center amplitude ratio of the fourth harmonic to the second harmonic is -1.44%, and the maximum relative error of the modulation depth simulation to the theoretical value is 1.78%. The experimental results show that the modulation depth value is calculated based on the modulation depth function. When m=2.226 7, the measured central frequency amplitude of the second harmonic reaches the maximum value. When m=4.061 0, the measured central frequency amplitude of the fourth harmonic reaches the maximum value, which is consistent with the theoretical results. When 30.2 kPa<p<177.9 kPa, the relative error between the modulation depth and the pressure product MP value is small. The maximum relative error is not more than ±3.2%. It shows that the MP value under this pressure does not fluctuate much. The modulation depth value calculated by the modulation depth function approximates the actual value, which verifies the accuracy of the modulation depth function theory.
|
|
Received: 2020-11-27
Accepted: 2021-02-19
|
|
|
|
[1] CHEN Hao，JU Yu，HAN Li，et al(陈 昊，鞠 昱，韩 立，等）. Spectroscopy and Spectral Analysis（光谱学与光谱分析），2020, 40(10): 3015.
[2] LI Ming-xing，CHEN Bing，RUAN Jun，et al（李明星，陈 兵，阮 俊，等）. Optics and Precision Engineering（光学精密工程）, 2020, 28(7): 1424.
[3] Lee Jungwun, Bong Cheolwoo, Yoo Jihyung, et al. Optic Express，2020, 28(14): 21121.
[4] YAO Lu，LIU Wen-qing，LIU Jian-guo，et al（姚 路，刘文清，刘建国，等）. Chinese Journal of Lasers（中国激光），2015, 42(2): 0215003.
[5] LI Min，BO Feng-ming（李 珉，柏逢明）. Laser Journal（激光杂志）, 2015, 36(10): 75.
[6] QU Dong-sheng，HONG Yan-ji，WANG Guang-yu，et al（屈东胜，洪延姬，王广宇，等）. Journal of Infrared and Millimeter Waves（红外与毫米波学报）, 2016, 35(4): 470.
[7] ZHANG Ke-ke，LIU Shi-xuan，CHEN Shi-zhe, et al（张可可，刘世萱，陈世哲，等）. Instrument Technique and Sensor（仪表技术与传感器）, 2016，(1): 53. |
| [1] |
TIAN Fu-chao1, CHEN Lei2*, PEI Huan2, BAI Jie-qi1, ZENG Wen2. Study of Factors Influencing the Length of Argon Plasma Jets at
Atmospheric Pressure With Needle Ring Electrodes[J]. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2023, 43(12): 3682-3689. |
| [2] |
ZENG Si-xian1, REN Xin1, HE Hao-xuan1, NIE Wei1, 2*. Influence Analysis of Spectral Line-Shape Models on Spectral Diagnoses Under High-Temperature Conditions[J]. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2023, 43(09): 2715-2721. |
| [3] |
YANG Fan1, HAO Liu-cheng1, KE Wei2, LIU Qing1, WANG Jun1, CHEN Min-yuan2, YUAN Huan2*, YANG Ai-jun2, WANG Xiao-hua2, RONG Ming-zhe2. Research on Effect of Laser Incident Angle on Laser-Induced Plasma at Low Pressure[J]. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2023, 43(09): 2740-2746. |
| [4] |
PAN Ke-yu1, 2, ZHU Ming-yao1, 2, WANG Yi-meng1, 2, XU Yang1, CHI Ming-bo1, 2*, WU Yi-hui1, 2*. Research on the Influence of Modulation Depth of Phase Sensitive
Detection on Stimulated Raman Signal Intensity and
Signal-to-Noise Ratio[J]. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2023, 43(04): 1068-1074. |
| [5] |
PENG Wei, YANG Sheng-wei, HE Tian-bo, YU Ben-li, LI Jin-song, CHENG Zhen-biao, ZHOU Sheng*, JIANG Tong-tong*. Detection of Water Vapor Concentration in Sealed Medicine Bottles Based on Digital Quadrature Phase-Locked Demodulation Algorithm and TDLAS
Technology[J]. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2023, 43(03): 698-704. |
| [6] |
ZHANG Le-wen1, 2, WANG Qian-jin1, 3, SUN Peng-shuai1, PANG Tao1, WU Bian1, XIA Hua1, ZHANG Zhi-rong1, 3, 4, 5*. Analysis of Interference Factors and Study of Temperature Correction Method in Gas Detection by Laser Absorption Spectroscopy[J]. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2023, 43(03): 767-773. |
| [7] |
ZHANG Bo-han, YANG Jun, HUANG Qian-kun, XIE Xing-juan. Research on Gas Pressure Measurement Method Based on Absorption Spectroscopy and Laser Interference Technology[J]. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2022, 42(12): 3692-3696. |
| [8] |
LONG Jiang-xiong1, 2, ZHANG Yu-jun1*, SHAO Li1*, YE Qing1, 2, HE Ying3, YOU Kun3, SUN Xiao-quan1, 2. Traceable Measurement of Optical Path Length of Gas Cell Based on Tunable Diode Laser Absorption Spectroscopy[J]. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2022, 42(11): 3461-3466. |
| [9] |
YANG Jin-chuan1, 2, AN Jing-long1, 2, LI Cong3, ZHU Wen-chao3*, HUANG Bang-dou4*, ZHANG Cheng4, 5, SHAO Tao4, 5. Study on Detecting Method of Toxic Agent Containing Phosphorus
(Simulation Agent) by Optical Emission Spectroscopy of
Atmospheric Pressure Low-Temperature Plasma[J]. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2022, 42(06): 1728-1734. |
| [10] |
LI Cong-cong1, LUO Qi-wu2, ZHANG Ying-ying1, 3*. Determination of Net Photosynthetic Rate of Plants Based on
Environmental Compensation Model[J]. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2022, 42(05): 1561-1566. |
| [11] |
CHEN Yang, DAI Jing-min*, WANG Zhen-tao, YANG Zong-ju. A Near-Infrared TDLAS Online Detection Device for Dissolved Gas in Transformer Oil[J]. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2021, 41(12): 3712-3716. |
| [12] |
ZHANG Xiao-lin1, LI Shou-zhe2*, JI Chun-jun1*, NIU Yu-long2, BAI Yang2, LIAO Hong-da2. Spectral Study on Combustion Supporting Effect of Plasma Jet for Methane Combustion in Air[J]. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2021, 41(10): 3251-3255. |
| [13] |
WANG Guo-shui1, GUO Ao2, LIU Xiao-nan1, FENG Lei1, CHANG Peng-hao1, ZHANG Li-ming1, LIU Long1, YANG Xiao-tao1*. Simulation and Influencing Factors Analysis of Gas Detection System Based on TDLAS Technology[J]. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2021, 41(10): 3262-3268. |
| [14] |
CHEN Chuan-jie1, 2, FAN Yong-sheng3, FANG Zhong-qing1, 2, WANG Yuan-yuan1, 2, KONG Wei-bin1, 2, ZHOU Feng1, 2*, WANG Ru-gang1, 2. Research on the Electron Temperature in Nanosecond Pulsed Argon Discharges Based on the Continuum Emission[J]. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2021, 41(08): 2337-2342. |
| [15] |
SONG Peng1,3, LI Zheng-kai2, CHEN Lei2*, WANG Xiao-fang1, LONG Wu-qiang1, ZENG Wen2. Diagnosis of Atmospheric Pressure Helium Cryogenic Plasma Jet[J]. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2021, 41(06): 1874-1879. |
|
|
|
|
