Researchers at Princeton University have found way to use lasers to check blood glucose levels in diabetics.

Currently, diabetics use needles to draw out blood samples to measure glucose levels. Other researchers have been trying to use breath, skin patches to estimate blood sugar levels. Google and drugmaker Novartis have even teamed-up to develop smart contact lenses to monitor levels of sugar in diabetic' blood.

The latest technique can help people with diabetes better take of their health and that too without using invasive blood tests.

Researchers are yet to shrink the size of the equipment that users lasers to check for blood sugar levels. However, the study shows that the method works.

"We are working hard to turn engineering solutions into useful tools for people to use in their daily lives," said Claire Gmachl, the Eugene Higgins Professor of Electrical Engineering and the project's senior researcher, according to a news release. "With this work we hope to improve the lives of many diabetes sufferers who depend on frequent blood glucose monitoring."

Their study is published in the journal Biomedical Optics Express. Researchers say that they exposed palms of diabetics to a special kind of laser. The laser penetrated the cells and was absorbed by sugars in blood. The amount of absorption helped researchers estimate sugar levels in blood.

"It works now but we are still trying to improve it," said Liakat, a graduate student in electrical engineering.

The team uses Mid-infrared light in their glucose-measuring device rather than near-infrared light, which is a standard for most medical devices.

A key problem in the study was that mid-infrared light is notoriously difficult to harness with standard lasers. The team relied on a new type of device called a quantum cascade laser to generate the desired lasers.

When researchers began the study, the equipment they used filled up an entire workbench and required elaborate cooling system. The team has been able to get the system function at room temperature now. They plan on further reducing the size of the device to make it more portable.