Embodiments concern coupling polarized light at two or more wavelengths across the aqueous humor of the eye (e.g., as part of a noninvasive glucose monitoring system). An approach discloses non-contact and minimal contact eye-coupling designs that are part of a system for providing glucose concentration levels via measurements acquired by passing two or more optical beams through the cornea/aqueous chamber in the eye. The approach provides for coupling the light to account for the index mismatch incurred while allowing for monitoring the light polarization. Specifically, in an embodiment the light transitions from the device, through the air, through the proximal side of the cornea, through the aqueous humor, through the medial side of the cornea, and through the air back into the device. Embodiments address the index of refraction mismatch and polarized light maintaining concerns with a coupling approach that can take the form of contact and non-contact mechanisms.
