Interference effects in measurements of the absorption coefficients of transparent materials

A theoretical analysis is made of the influence of interference effects on the measured absorption coefficients of plane-parallel low-loss plates. Estimates are obtained of the error in the loss determination due to indeterminacy of the ratio of the thickness of the sample to the wavelength of the incident radiation. Experimental observations are reported of pulsations of the intensity of the radiation transmitted by a sample and the frequency of such pulsations is proportional to the power of the radiation absorbed by the sample.