Measuring object gas absorbs specific wave range infrared radiation and uses the principle of displaying the corresponding concentration absorbed. The bleeding from the source of light is measured by the detector after the measuring object gas passes through the infrared radiation. Light is absorbed from the measuring object gas and the difference of the light quantity from the infrared radiation absorbed by the detector is generated.

The sensing detection has an optical filter which eliminates measurement of the unneeded wave lengths of infrared radiation. The interference effect can be reduced to a minimum from only measuring the specific wave range of infrared radiation. Using the double beam method and using the reference side volume of light as the base on the basis of the Lambert-Beer formula the differences in the light volume of the sample side and the reference side the change of the light source volume of light, the detector alterations and the contamination of the light materials from the change of light on the window materials can be cut and long term stable measurements can be realized.

Measurement image