Forget Flat Screens
UCSB researchers developed a touchscreen that uses lasers and shape-shifting pixels to make the display come alive.
Touchscreens have dominated user interfaces for more than a decade because of their intuitive nature, versatility, and ability to present dynamic content. But these displays are not perfect. In fact, they have a major flaw: they provide no tactile feedback. This makes for a very hollow user experience when compared to traditional physical controls, making it difficult for users to confidently interact without constantly looking at the screen, especially for tasks like typing or operating controls while driving.
A group of researchers at UC Santa Barbara is working to change that. They have developed a novel type of touchscreen that can morph its shape on demand, allowing users to feel what they are seeing. It may not be everything that we dream of in a tactile display, but the individually-addressable pixels can each extend upward by up to a millimeter on command.
Just add lasers
The researchers’ system is built on a simple but fascinating idea: using light itself as both the power source and the control signal for each tactile pixel. The team created thin display surfaces embedded with arrays of “optotactile” pixels—tiny air-filled cavities capped by a flexible membrane and containing a suspended graphite film. When struck by a brief pulse from a low-power laser, the graphite layer rapidly heats, the trapped air expands, and the membrane bulges outward to form a perceptible bump.
This approach allows the team to sidestep one of the biggest barriers in tactile display engineering: wiring. Because each pixel requires only targeted light to activate, the surface contains no embedded electronics. A small scanning laser sweeps the display, energizing pixels one by one at high speed — something like an old CRT TV. This happens fast enough to create continuous visible and touchable animations. Early prototypes include more than 1,500 independently controllable pixels, a density that surpasses most tactile displays reported to date.
A touching response
User studies suggest this approach has a lot of potential. Participants were able to locate individual raised pixels with millimeter-level accuracy, track moving shapes, and distinguish complex spatial and temporal patterns. These results demonstrate a wide expressive range for the technology, from simple cues to rich touch-based graphics.
The team imagines future applications such as automotive touchscreens that mimic mechanical switches, e-readers with tactile illustrations, and large-scale architectural installations that blend physical and digital interaction. While still early in development, the work could ultimately bring us closer to interfaces that not only look dynamic, but feel alive.