A glucose sensor comprising an optical energy source having an emitter with an emission pattern； a first polarizer intersecting the emission pattern； a second polarizer spaced a distance from the first polarizer and intersecting the emission pattern, the second polarizer rotated relative to the first polarizer by a first rotational amount &Theta；； a first optical detector intersecting the emission pattern； a second optical detector positioned proximal to the second polarizer, the first polarizer and the second polarizer being positioned between the optical energy source and the second optical detector, the second optical detector intersecting the emission pattern； a compensating circuit coupled to the second optical detector； and a subtractor circuit coupled to the compensating circuit and the first optical detector.
