Non-invasive blood glucose monitoring by interferometry

An apparatus for monitoring glucose fluctuations by measuring properties of an eye:

• a light source which emits a beam of light;
• an optical element situated to receive said beam of light from said light source and to split said beam of light into first and second probe beams that propagate along respective first and second optical paths;
• at least one optical element in one of said optical paths to alter said optical path such that first and second probe beams intersect at a target plane;
• and
• an optical detector and imaging optics for imaging said target plane on said optical detector.

A method of monitoring glucose levels in blood of a living being having an eye, said method comprising:

• propagating light through a portion of said eye comprising aqueous humor having an index of refraction that varies with glucose concentration;
• obtaining phase information associated with said light through optical interference, said phase information depending at least in part on said index of refraction of said aqueous humor;
• and
• using said phase information to determine said glucose levels in said blood.

A method of aligning a device with respect to a cornea, said cornea having a substantially spherical curvature defined by a center of curvature, said method comprising:

• propagating light toward said cornea, said light having substantially spherical wavefronts defined by a center of curvature that is substantially coincident with said center of curvature of said cornea;
• retroreflecting a portion of said light from said cornea;
• collecting said retroreflected light;
• and
• focusing said collected light on an optical detector having a photosensitive area such that when said center of curvature of said wavefronts is substantially coincident with said center of curvature of said eye, said light focused on said photosensitive area has a different intensity than when said respective centers of curvature are non-coincident.