A Switchable Optically Variable Ink (SOVI)

Dr Bandhu describes a novel Switchable Optically Variable Ink (SOVI), which has the capability to switch between two stable, highly contrasting colour states (generated by an optical nano-cavity featuring ultra-thin phase change materials PCM), using a simple laser...

Laser personalized DOVID based on double metal layer systems

We present novel ideas of combining optically variable devices with laser personalization for secondary image creation and protection. Three-layer systems are laser processed to drastically change their appearance from, for example, black to mirror-like, transparent...