An apparatus and method for determining the concentration of chiral
molecules in a fluid includes a first polarizer configure to polarize
light in substantially a first plane to provide initially polarized
light. A second polarizer is capable of polarizing the initially
polarized light in a plurality of planes, at least one of the plurality
of planes being different from the first plane, to provide subsequently
polarized light. One or more receivers are included for measuring an
intensity of the subsequently polarized light in one or more of the
plurality of planes.