A Chinese research team recently develop a stretchable light-emitting devices which delivers information and can be attached to human skin and other surfaces. The device is like a temporary tattoo and can be operated at low voltage so it does not cause harm to users.

Published in ACS Materials Letter in October 2019, the results from researchers at Nanjing University in China demonstrated stretchable light-emitting devices called alternating-current electroluminescent (ACEL) displays. The device has a sandwiched structure with an electroluminescent layer made of light-emitting microparticles dispersed in a stretchable dielectric material and two flexible silver nanowire electrodes.

A new type of dielectric material that is in the form of ceramic nanoparticles embedded in a rubbery polymer helps to increase the brightness of the device compared with existing ACEL displays. The researchers used this material to make a four-digit stopwatch display mounting onto a volunteer’s hand. The display deliver sufficient brightness under indoor lighting with low voltages.

(Image:ACS Materials Letters)

The researchers believe that the stretchable epidermal display can be implement for a wide range of applications in smart wearables, soft robotics and human-machine interfaces.