Low-cost method creates any colour filter

Their method is claimed to be a fast, low-cost alternative to colour filters currently used in electronic displays and monitors.

‘Our technique doesn’t require expensive nanofabrication techniques or a lot of materials,’ said Koray Aydin, assistant professor of electrical engineering and computer science at Northwestern’s McCormick School of Engineering. ‘And it can be completed in a half hour or so.’

Aydin and his team created a three-layer design, where glass is wedged two thin layers of silver film. The silver layers are thin enough to allow optical light to pass through, which then transmits a certain colour through the glass and reflects the rest of the visible spectrum. By changing the thickness of the glass, Aydin was able to filter and produce different colours.

‘Controlling the thickness of the glass controls the colour,’ Aydin said in a statement. ‘This way, we can create any colour desired.’

Supported by the US Air Force Office of Scientific Research, the research was published online in ACS Photonics on January 28, 2015. PhD student Zhongyang Li and postdoctoral researcher Serkan Butun, who are both in Aydin’s lab, were co-authors of the paper.