Abstract: A method and apparatus for analyzing the absorption spectra of a minute sample. The sample is placed in a hollow enclosure which is sealed after a suitable working fluid is introduced into the enclosure. When a vapor equilibrium is reached within the enclosure creating a droplet condensate of working fluid about the sample, the sample is first irradiated with dark-field visible illumination with an image thereof stored, and is then irradiated with infrared radiation and a second dark-field image stored. The stored images are analyzed and the procedure is repeated for a plurality of different frequencies spanning the range of infrared absorption of the sample.