Skip to Content
Find More Like This
Return to Search

Detection of birefringent microcrystals in bile

United States Patent

September 30, 2003
View the Complete Patent at the US Patent & Trademark Office
Lawrence Livermore National Laboratory - Visit the Industrial Partnerships Office Website
A transparent flow channel fluidly communicates a fluid source and a collection reservoir. A light beam passes through a first polarizer having a first plane of polarization. The flow channel is orthogonal to the light beam. The light beam passes through a fluid sample as it flows through the flow channel. The light beam is then filtered through a second polarizer having a second plane of polarization rotated from the first plane of polarization. The birefringence of certain crystalline materials present in the fluid sample rotates the plane of polarization of the light beam. The presence of these microcrystals thus causes a component of the beam to pass through the second polarizer and impinge an electronic photo-detector located in the path of the beam. The photo-detector signals the presence of the microcrystals by generating voltage pulses. A display device visually presents the quantitative results of the assay.
Darrow; Chris (Pleasanton, CA), Mirhej; Andrew (San Francisco, CA), Seger; Tino (Berlin, DE)
The Regents of the University of California (Oakland, CA)
09/ 815,087
March 21, 2001
The United States Government has rights in this invention pursuant to Contract No. W-7405-ENG-48 between the United States Department of Energy and the University of California for the operation of Lawrence Livermore National Laboratory.