Being able to monitor a person’s health while allowing them to go about their daily lives can be tough. You need sensors that can be attached to the body in such a way as the patient forgets they are even wearing them. Weight, bulk, and the need for batteries to power everything currently make such a setup less than ideal.Progress is being made, though, and in the area of on-body sensors the University of Tokyo has made a breakthrough. A research group there has managed to create a sensor sheet that’s incredibly light, to the point where it would be very difficult to know it is even attached to your body.So how light is this sensor sheet? Well, a typical sheet of paper weighs 81g/m2. The sensor sheet is only 3g/m2, or 1/27th the weight of the paper. It’s also incredibly thin, measuring just 2 micrometers.As it’s a flexible sheet, it can be cut to a range of sizes and will wrap around the contours of the body quite easily. A number of medical sensors can be integrated with it, allowing for monitoring of body temperature, heart rate, blood pressure, and any number of other body-related information we have skin sensors available for.The sensor sheet is actually a progression of technology developed in 2010 that placed an array of organic TFTs on to a plastic film substrate. The end result was a flexible pressure sensor sheet 25 micrometers thick. In this latest version the thickness has been reduced by 90 percent to just 2 micrometers.It’s probably going to be a while before we see doctors using this super lightweight sheet to monitor their patient’s health. Currently the research group has just finished a thesis on the technology, although they have usable prototypes of the sheet in their lab.