HOME > Technology > Principles of NDIR Technology
Principles of NDIR Technology
|Category||NDIR Sensors||Touch Sensors|
|Basics||Density is measured by assessing the optical absorbance of different types of gases absorbing infrared rays of specific wavelengths.||Density is measure by assessing chemical changes that occur upon coming in contact with gas molecules.|
|Types||Non-dispersive infrared Type
|Semi-conduct and solid-electrolyte Type
|Difference||High accuracy by only detection of specific gases. Not influenced by other vapors and VOC gases.
(Measure the energy difference before and after CO2 or CO absorbed its corresponding NDIR light frequency)
|Not chosen for most application because its inaccuracy and unstability are get unbearably worse with time due to too limited and vulnerable technological ground.|
|Strength||Longevity over 10 years, high accuracy, no interference||small size and low price in sensor elements|
|Weakness||Relatively larger size and higher price, however, the total price has shown a lower in long life time||Short life time in 2~5 year, low accuracy, interfered by other gases.|
|Evaluation||As average prices of NDIR sensors get lower and the more touch sensors are getting replaced.|
What is a non-dispersive infrared (NDIR) gas sensor ?