INFRARED ABSORBING TYPE GAS CONCENTRATION MEASURING METHOD AND APPARATUS

• Main Authors: KAWAZU NARIYUKI, SHIOZAWA MASAHIRO, NITTA TAKAHIRO
• Format: Patent
• Language: English
• Published: 05.11.1999
• Edition: 6
• Subjects: COLORIMETRY; INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIRCHEMICAL OR PHYSICAL PROPERTIES; MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT,POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRA-RED,VISIBLE OR ULTRA-VIOLET LIGHT; MEASURING; PHYSICS; RADIATION PYROMETRY; TESTING

PROBLEM TO BE SOLVED: To accurately measure the concn. of gas even if the absorption or noise radiation of infrared rays emitted into a cell is changed in an infrared absorbing type gas concn. measuring method. SOLUTION: The temp. conditions of cells 1A, 1B are changed and, under the respective temp. conditions, the changeover of introduced reference gas, the change over of the emission of infrared rays into the cells 1A, 1B and the stop of the emission thereof and the changeover of the cell 1A equipped with a light permeable window 13 and the cell 1B not equipped therewith are performed and, from the detection output of a detector 32 at this time, the absorption and noise radiation of infrared rays emitted into the cells 1A, 1B are determined and, on the basis of the absorption and noise radiation of infrared rays coinciding with the temp. condition at a time when the sample gas is introduced into the cell 1A, the detection output of the sample gas is corrected and the concn. of the gas to be measured in the sample gas is obtained without receiving the effect of a temp. range.