A brief analysis of the components of infrared gas sensor

　　What are the components of infrared gas sensor? Infrared gas sensor is a kind of detection device for gas detection. It has certain applications in many industries. When we use infrared gas sensor, we need to master the composition of infrared gas sensor. The following Xiaobian will introduce it in detail.

　　The infrared gas sensor in the gas alarm controller has the basic components: an infrared source (i.e., incandescent lamp), probe (e.g., thermal battery, fireworks probe), method of selecting the appropriate wavelength (e.g., light strip through the interference filter) and sample element. Radiation is transmitted from the radiation source through the sample element and wavelength selector.Wavelength selection has considerable influence on the relative selectivity of sensor.The radiation not absorbed by the sample is measured by the probe, which provides a measurement of the concentration value of the target gas in the sample.Another probe (or channel) in the sample is set to a different wavelength and will not be diluted by any possible wavelength in the sample, which is often used to provide a reference measurement.

　　Another element that enhances the performance of the infrared sensor is the temperature sensor.All these components of the gas alarm controller shall be compensated by temperature attachments to provide accurate gas concentration values.The temperature sensor (usually a thermistor) should be placed in or very close to the probe. Infrared sensor can provide effective measurement values for target gas molecules between infrared source and probe.Therefore, the output signal changes not only with the gas concentration, but also under the influence of pressure. In order to ensure the high accuracy of measurement, pressure compensation must be provided.This indicates that sensors with longer optical paths (radiation distance from radiation source to probe) have higher sensitivity, requiring a lower mechanical range but increased resolution.

　　If the target gas is a gas and the gas alarm controller device is under constant pressure, the output signal (and signal/sound ratio) will show a tendency similar to exponential decay as the gas concentration increases, that is, the infrared sensor is a fixed nonlinear sensor.The accuracy of the measurement decreases with increasing gas concentration.The more common detection technique is to use amplification equipment to amplify the smaller analog signal output by the probe. The amplified output signal can improve the accuracy of measurement after being simulated and filtered.