Diabetes patients traditionally monitor their daily blood glucose levels by sampling blood from the finger tips. Tohoku University researchers have developed a non-invasive method of measuring blood glucose using far infrared light.

The technique works on the premise that near infrared light of some specific wavelengths are selectively absorbed by glucose in the blood. In contrast, far infrared light with wavelengths of around 10 micron is strongly absorbed by glucose, making it possible, in theory, for patients to get more sensitive and accurate measurements.

To radiate far infrared light, a small prism is attached to ends of flexible hollow-optical fibers.

Results from experiments show blood glucose levels sensitively detected and accurately measured with a less than 20% margin of error. Professor and lead researcher Yuji Matsuura expects compact and low-cost blood glucose measurement systems to soon be widely used in clinical fields.