Xu Maosen, Tian Wei, Lin Yuzhe, Xu Yan, Tao Jifang
College of Electrical Engineering and Automation, Shandong University of Science and Technology, Qingdao 266590, China.
College of Electronic and Information Engineering, Shandong University of Science and Technology, Qingdao 266590, China.
Micromachines (Basel). 2024 Sep 28;15(10):1203. doi: 10.3390/mi15101203.
A carbon dioxide (CO) gas sensor based on non-dispersive infrared (NDIR) technology has been developed and is suitable for use in portable devices for high-precision CO detection. The NDIR gas sensor comprises a MEMS infrared emitter, a MEMS thermopile detector with an integrated optical filter, and a compact gas cell with high optical coupling efficiency. A dual-ellipsoid mirror optical system was designed, and based on optical simulation analysis, the structure of the dual-ellipsoid reflective gas chamber was designed and optimized, achieving a coupling efficiency of up to 54%. Optical and thermal simulations were conducted to design the sensor structure, considering thermal management and light analysis. By optimizing the gas cell structure and conditioning circuit, we effectively reduced the sensor's baseline noise, enhancing the overall reliability and stability of the system. The sensor's dimensions were 20 mm × 10 mm × 4 mm (L × W × H), only 15% of the size of traditional NDIR gas sensors with equivalent detection resolution. The developed sensor offers high sensitivity and low noise, with a sensitivity of 15 μV/ppm, a detection limit of 90 ppm, and a resolution of 30 ppm. The total power consumption of the whole sensor system is 6.5 mW, with a maximum power consumption of only 90 mW.
一种基于非分散红外（NDIR）技术的二氧化碳（CO）气体传感器已被开发出来，适用于高精度CO检测的便携式设备。该NDIR气体传感器包括一个MEMS红外发射器、一个带有集成光学滤波器的MEMS热电堆探测器以及一个具有高光耦合效率的紧凑型气室。设计了一种双椭球镜光学系统，并基于光学模拟分析对双椭球反射气室的结构进行了设计和优化，实现了高达54%的耦合效率。进行了光学和热模拟以设计传感器结构，同时考虑了热管理和光分析。通过优化气室结构和调节电路，有效降低了传感器的基线噪声，提高了系统的整体可靠性和稳定性。该传感器的尺寸为20 mm×10 mm××4 mm（长×宽×高），在等效检测分辨率下仅为传统NDIR气体传感器尺寸的15%。所开发的传感器具有高灵敏度和低噪声特性，灵敏度为15 μV/ppm，检测限为90 ppm，分辨率为30 ppm。整个传感器系统的总功耗为6.5 mW，最大功率消耗仅为90 mW。
