×

Process and device for determining an analyte contained in a scattering matrix

  • US 5,962,852 A
  • Filed: 07/28/1997
  • Issued: 10/05/1999
  • Est. Priority Date: 01/26/1996
  • Status: Expired due to Term
First Claim
Patent Images

1. Method for determining an analyte in a scattering, in particular biological, matrix, in whichin a detection step detection measurements are carried out in which light is irradiated through an interface limiting the scattering matrix as primary light into the matrix and light leaving the scattering matrix through the interface is detected by a detector as secondary light, in order to determine as a measurement quantity a measurable physical property of the light which is variable due to the interaction of the light with the matrix, said interaction including optical absorption andin an evaluation step information on the presence of the analyte in the matrix is determined on the basis of a measured value of the measurement quantity measured in the detection step,wherein, using a confocal measuring arrangement, a first depth selection means is provided such that the primary light is focussed by means of a primary light optically focussing element onto a region of focus lying in the matrix at a depth of focus below the interface,the region of focus is imaged by means of a secondary light optically focussing element onto a light entry aperture arranged in the light path of the secondary light to the detector, the detection of the secondary light thereby being concentrated on the region of focus,wherein for generating a measurement signal allowing a selective analysis of an analyte which causes only a small share of the optical absorption, light reflected from a defined measuring depth below the interface is detected selectively as secondary light by a second depth selection means, the defined measuring depth coinciding with the depth of focus, and wherein the analyte comprises glucose.

View all claims
  • 2 Assignments
Timeline View
Assignment View
    ×
    ×