Abstract: A system for interrogating non-homogeneous liquid samples to locate regions of interest within the samples, and to extract liquid from the regions of interest. The system of the invention is particularly well adapted for use in locating and in thoroughly removing liquid from regions of interest that include even extremely thin, film-like, horizontally extending layers of interest that typically are in the range of about 10 to 50 microns in thickness. The system utilizes a polarized beam of collimated laser light that is projected along a horizontal travel path, that is transmitted through a sample, and that is detected to enable characteristics of the transmitted light beam that have been affected by characteristics of the interrogated sample portions to be studied.