Researchers at MIT are looking into using a spectograph to shine a near-infrared light on your skin and measures the vibrations to determine your blood sugar levels. This approach has some downsides. Most importantly, it measures the amount of glucose in your interstitial fluid (the fluid under your skin) rather than your blood. This is the same fluid measured by continuous glucose monitors.
When your blood sugars are changing quickly, it takes five minutes or more for your interstitial fluid to reflect the change. This matters when your blood sugars are rising or falling quickly. The device is also much bigger than your meter. The first prototypes of the device were as big as a cabinet. Now they are working on shrinking it down to the size of a laptop. It will be a while before it fits in a purse. But if they can make the device accurate enough, small enough, and affordable enough, it will quickly become an essential tool for managing diabetes. From Diabetes Daily — see full article here.