PURPOSE: To calibrate gas concentration without disturbing the measuring system of a gas concentration measurement system by reducing return light to a semi- conductor laser caused by reflections in a measurement light path.
CONSTITUTION: A cell chassis 34 forming a hermetically maintained calibrating gas chamber 33 is interposed between an aspheric surface lens 22 and a light receiving module 25 in a chassis 21 acting as a main body of a light receiving section 2. A gas intake pipe 53a and an exhaust pipe 53b for injecting/exhausting calibrating gas to the calibrating gas chamber, are projected out of the upper surface of the cell chassis 34 so as to be set in parallel. Gas with a concentration objective for calibration is injected in through the gas intake pipe 53a, and the detected value of gas concentration is calibrated at specified concentration intervals. When calibration is performed by using concentrated gas which is newly different, gas in the calibrating gas chamber 33 is exhausted through the exhausting pipe 53b once, and gas with a concentration objective for calibration, is injected in through the gas intake pipe 53a.
| JP4354383 | Semiconductor laser absorption spectrometer |
| JP5314301 | Gas concentration measurement method and equipment |
| WO/2020/159165 | INFRARED STEREO CAMERA |
KONDO KAZUKI
TAI HIDEO
TOKYO GAS CO LTD
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