METHOD AND APPARATUS FOR OPTICAL ANALYSIS OF THE CONTENTS OF A SHEATHED STREAM

摘要

There is provided a method and apparatus for optical analysis by photometry of a substance flowing in a liquid stream within a coaxial sheath stream of a transparent liquid. The sheath stream, flowing in the same direction, entrains the inner stream so as to confine it concentrically. A photometer is used which includes a light source on one side of the sheathed stream in a position to direct light onto the inner stream which is cylindrical, the outer or sheath stream also being cylindrical. The photometer also includes a light detector externally of the sheathed stream in an angular position to detect the photometric results of impingement of light on the contents of the inner stream. Refraction of light at the interfaces of the sheath stream is compensated by varying the radius of the inner stream through the control of the flow of one stream with reference to the other.