Dale Richard Yoder-Short

US Patent:

51683253, Dec 1, 1992

Filed:

Feb 28, 1990

Appl. No.:

7/486242

Inventors:

Dale R. Yoder-Short - Dollar Bay MI

Assignee:

Board of Control of Michigan Technological University - Houghton MI

International Classification:

G01B 902

US Classification:

356361

Abstract:

An apparatus and method for testing the glucose level in a blood sample is provided. The method includes the step of initially filtering a sample of blood to be tested. A beam of light is provided and split into a pair of beams by a beam splitter. The pair of beams travel along generally parallel paths. One path contains a cell of a known optical pathlength and additionally a compensator. The other path has a cell containing the filtered blood sample to be tested. The pair of beams are then recombined by a mirror and a fringe pattern is detected at a detector. From the fringe pattern, the refractive index of the blood sample can be calculated. The refractive index is easily converted to a specific glucose concentration. Alternatively, the original fringe pattern can be restored by changing the effect of the compensator. The refractive index can then be found from the required compensation.