The device works by sending a laser beam through skin cells - without causing damage - to be absorbed by sugar molecules. The target is not blood sugar as such, but the sugar content of dermal interstitial fluid, which has a strong correlation with blood sugar.
The new monitor uses a laser, instead of blood sample, to read blood sugar levels. The laser is directed at the person's palm, passes through skin cells and is partially absorbed by sugar molecules, allowing researchers to calculate blood sugar levels. The amount of absorption of the laser beam is thus an indicator of the amount of glucose in the blood. The challenge now is to improve the technology - and not least to bring down the scale.