METHOD FOR MEASURING OH CONCENTRATION USING LASER-INDUCED FLUORESCENCE METHOD

摘要

PURPOSE: To measure the OH concentration in a measuring field higher than the atmospheric pressure with high accuracy by matching the wavelength of a laser beam to the absorption band characteristic to OH at the time of starting measurement. ;CONSTITUTION: At the time of making a laser beam 3 incident to a measuring field 5 higher than the atmospheric pressure, the wavelength of the laser beam is matched to the (2, 0)-band 260-270mm) or (2, 1)-band (280-290mm) of the absorption bands of OH so that the OH concentration in the measuring field can be measured by detecting fluorescence generated by the laser beam. In the bands 260-270mm and 280-290mm, overlapping of absorption lines does not occur, because absorption lines of other molecules, such as O₂, etc., scarcely exist. When the field 5 is irradiated with the laser beam 3, the intensity of the beam 3 is little damped, because the quantity of background fluorescence is small and the beam 3 is not absorbed much.;COPYRIGHT: (C)1995,JPO