Belgian Researchers Develop Optical Circuit With Bendable Interconnections
Posted on February 19, 2014
Belgian researchers from Ghent University and Imec have developed an optical circuit with bendable and stretchable interconnections. The researchers say the new interconnections guide light along their path even when stretched up to 30% and bent around objects. The optical link could be used to build networks of wearable body sensors, better robotic limbs and deformable consumer electronics.
A rubbery transparent material, PDMS (poly-dimethylsiloxane), was used to create the optical circuits. The connector uses two materials made from PDMS: a transparent core through which the light travels, surrounded by another transparent layer of PDMS with a lower refractive index. The researchers say the configuration helps trap light in the guide's core.
The Belgian scientists say optical interconnections (also known as lightguides or waveguides) have been made before using other rubbery materials and semi-rigid glass fibers, but until now no one had discovered a way to make the materials carry light when stretched. When bent beyond a certain point a waveguide will begin to lose some of the light trapped in the core. This is known as optical loss. The researchers say they did not see a degradation in the lightguides they developed even after mechanically stretching it to a 10 percent elongation 80,000 times. The researchers plan to make their waveguide even smaller and reduce it from 50 micrometers to just a few micrometers in diameter.
A research paper about the breakthrough, "Stretchable optical waveguides," was published here in the journal, Optics Express.