Patent ID: 6603556
Filing Date: 2003-08-05
Classification: G01N

Abstract:
A photometric detection system for analyzing a sample fluid, the system comprising:a light source; a detector; a flow cell assembly including a tubular liquid core waveguide having an inlet end adapted for receiving a flow of the sample fluid and a discharge end adapted for discharging the flow of sample fluid, the inlet and discharge ends defining a length; first coupling means for optically coupling the light source to the waveguide at a first position along the length of the waveguide; second coupling means for optically coupling the detector to the waveguide at a second position along the length of the waveguide, the second coupling means comprising a plurality of collector optical fibers, each of the collector optical fibers having oppositely disposed light receiving and light emitting ends, the light receiving end of each collector optical fiber being coupled to the waveguide at a collection position longitudinally spaced from the collection position of each other collector optical fiber, the first and second positions defining an optical path length; and means for varying the second position relative to the first position whereby the optical path length is selectively varied.