Research on the Effect of Light Intensity Modulation on the Line Shape of the Second Harmonic in the Wavelength Modulation Technology

Yajun, 胡雅君 Hu; Xuehong, 赵学玒 Zhao; Rui, 张锐 Zhang; Yuan, 郭媛 Guo; Yan, 汪曣 Wang

doi:10.3788/aos201333.1130002

Cited by 4 publications

(1 citation statement)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…At present, WMS-2f/1f normalized signals are used as the output signals 10 , which can eliminate the influence of laser power attenuation and other factors on the system. However, when the second harmonic signal is extracted, the first harmonic signal should be extracted synchronously 11 . The system needs two phase locked unit, which will increase the complexity of the hardware circuit.…”

Section: Principle Of Wavelength Modulationmentioning

confidence: 99%

Research on CO2 concentration detection technology based on tunable diode laser absorption spectroscopy

Zhang,

Yang

et al. 2023

Semiconductor Lasers and Applications XIII

View full text Add to dashboard Cite

In the observation of CO2 flux, high-speed and high-precision measurement of CO2 concentration is an urgent problem to be solved, and the collection frequency of CO2 concentration must be greater than 10Hz. The Tunable Diode Laser Absorption Spectroscopy (TDLAS) technology is widely used in various gas monitoring fields with high requirements for sensitivity, response time, and no background gas interference. In this paper, interband cascade laser at 4.26 micron is used as the system light source, and the second harmonic peak-peak value and the Root Mean Square (RMS) of sinusoidal are used to measure the CO2 concentration. When the laser CO2 analyzer was developed, comparative experiments were conducted using LI-7500DS and self-developed equipment. The CO2 concentration values measured by the laser gas analyzer and the LI-7500DS gas analyzer are synchronously collected using a sampling frequency of 10 Hz. The experimental results show that the trend of CO2 concentration measured by the two devices is consistent, and deviation of CO2 concentration is within ±2%, which can meet the needs of carbon dioxide flux measurement.

show abstract

Section: Principle Of Wavelength Modulationmentioning

confidence: 99%