Stretchable skin sensors were the rage a few years ago, yet disappeared off the radar well before the pandemic. A good part of it was that the sensor tech was confined to university labs and small companies attempting to commercialize it into ‘smart clothing’ paired with a smartphone, a form factor that never found a market. Since those early days, what has entered the mainstream are sensors/smartphone combinations for blood glucose reporting. So it’s positive that Samsung, expert at commercialization and the technology around displays, has set its R&D unit, the Samsung Advanced Institute of Technology (SAIT), to developing a prototype stretchy skin patch for vital signs monitoring that combines both a sensor and display.
SAIT developed a sensor (left) that combined a stretchable LED (OLED) display and a photoplethysmography (PPG) sensor. The tests applied it to the inner wrist near the radial artery to measure and display heart rate in real time.
The device uses a combination of elastomer, a polymer compound with excellent elasticity and resilience, with existing semiconductor manufacturing processes to apply it to the substrates of stretchable OLED displays and optical blood flow sensors.
The study found that the sensor achieved:
- Stable performance in a stretchable device with high elongation. The display can be stretched up to 30 percent.
- The movement of the arm did not affect the OLED display
- The adhesion and location of the display and sensor made, in their findings, continuous heartbeat measurements possible with a high degree of sensitivity compared to existing fixed wearable sensors
The researchers claim this is for the first time in the industry and proves the commercialization potential of stretchable sensors. While the OLED display leaves a lot to be desired in readability and it seems chunky, it’s another step in creating more easily worn ‘all in one’ monitoring devices that stretch to fit, don’t require a wristband, or constant checking on one’s phone. The SAIT research was just published in Science Advances, 4 June. Samsung release, The Verge, Mobihealthnews