Patent ID: 6844553
Filing Date: 2005-01-18
Classification: G01N

Abstract:
1. An absorption spectroscopy apparatus having a fluid inlet and a fluid outlet and comprising: a sample cell including an axis, a side wall having at least one curved reflective surface arrayed about the axis and facing inwardly with respect to the axis such that a beam of energy directed against a predetermined location on the reflective surface is reflected back and forth off the reflective surface and remains in substantially the same plane while inside the cell, and at least one port in the sidewall, and end walls closing ends of the side wall and having flat reflective surfaces facing inwardly with respect to the cell and lying in a plane extending substantially perpendicular to the axis of the cell, wherein the cell has a height measured in a direction parallel to the axis substantially equal to a source length and an energy path in the cell is substantially perpendicular to the cell axis; and at least one source/detector reflector comprising a segment of a cylinder having a curved profile in a plane extending perpendicular to the axis of the cell, the reflector positioned with respect to the port of the cell to reflect energy through the port of the cell and against the predetermined location on the reflective surface of the side wall of the cell.