A non-dispersive infrared (NDIR) spectrum analysis was used to design a carbon dioxide sensor which is non-modulating and double-wavelength.

基于非色散红外（NDIR）光谱分析原理，设计了一种非调制双波长二氧化碳传感器。

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The non-dispersive infrared method (NDIR) is used to measure CO, CO2 and HC;

使用非扩散红外线（NDIR）光吸收方法分析HC、CO和CO2质量分数；

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