METHOD FOR ANALYSIS OF A SAMPLE OF A SUBSTANCE BY MEANS OF PHOTOACOUSTIC OR OPTOTHERMAL SPECTROSCOPY AND A SAMPLE CARRIER FOR PERFORMING OF THE METHOD

摘要

ABSTRACTA method for analysis by a sample of a substance by means ofphotoacoustic or optothermal spectroscopy. The sample ofsubstance is applied on a sample carrier , which is sodimensioned that 0.01?a.b?10 for the sample carrier with thesample at the intended wavelength and the modulationfrequency, where a is the absorption coefficent of the sampleand b is the thermal diffusion length for the sample at theintended modulation frequency. The sample carrier with sampleis brought to close contact with the photoacoustic oroptothermal detector of the measurement cell, where themeasuring can be carried out. For a sample carrier withseveral layers, the layer facing the detector is demensionedwith a thickness which is at least one diffusion length b forthe intended sample and the modulation frequency. Theinvention also relates to sample carriers intended to beused for performing the method.P13551SE-2042/84101983