Portable laser demonstrator for printable liquid crystal laser materials
A research team at the University of Cambridge have developed a method to print lasers made from LC materials using inkjet printing equipment.
Usuallly, tuneable laser systems, such as Ti:sapphire and dye lasers, are large, fixed, complex and expensive. These lasers are made from materials which require expensive manufacturing processes and only work on certain surfaces.
The printable laser materials are made from cholesteric LCs, which are aligned by the application of standard polyvinyl acetate (PVA) polymer on a substrate, such as glass, using a simple bar-coating method. The laser deposits, each less than 500 microns in width, are then printed onto the polymer.
The colour of the laser emission is controlled by a chiral additive and fluorescent dye. The printed LC lasers can emit light anywhere in the 400 to 850 nm range. The research team at the Centre of Molecular Materials for Photonics and Electronics (CMMPE), working under the EPSRC funded COSMOS project, collaborated with the Inkjet Centre at the IfM, both in the Department of Engineering at the University of Cambridge.
The discovery could lead to a low-cost and compact alternative to existing tuneable laser technology enabling a host of new applications for lasers, such as functionalising large area surfaces to create displays on walls. The technology also promises a low-cost method for making bioassay arrays for detecting viruses and pathogens, which could benefit healthcare and other sectors. Brand protection and security printing could also benefit from the technology as the lasers can be deposited on a range of coated substrates, including plastic film and even paper.
In order to demonstrate the potential of this promising technology for the security industry, the research team used a small grant from the CIKC to build a compact, A4 footprint, portable demonstrator to probe printed laser films.
Dr Damian Gardiner, who worked on the project, explains: ‘CIKC funding in the Portable Printable Laser Demonstrator (PORTALS) project has been used to bridge the gap between fundamental research and making a prototype detector to “read” the light emission from the printed LC lasers and confirm laser operation.
Having a portable prototype is really important as it means we can show a working demonstrator to potential investors, customers and development partners, so they can see how simply it can be utilised or deployed.’
After completion of the project, Gardiner and his colleagues worked with the University’s organisation i-Teams, which takes PhD students and post-docs and exposes them to a new technology or invention and examines potential applications. He also engaged with Cambridge Enterprise, the University’s technology transfer arm, to formulate commercial exploitation opportunities and ideas. Gardiner recently secured a Royal Academy of Engineering Enterprise Fellowship to pursue commercialisation routes currently under discussion.