Disney researchers have found a way for people to "feel" the texture of objects seen on a flat touchscreen.
The technique involves sending tiny vibrations through the display that let people "feel" the shallow bumps, ridges and edges of an object.
The vibrations fooled fingers into believing they were touching a textured surface, said the Disney researchers.
The vibration-generating algorithm should be easy to add to existing touchscreen systems, they added.
Developed by Dr Ali Israr and colleagues at Disney's research lab in Pittsburgh, the vibrational technique re-creates what happens when a finger tip passes over a real bump.
"Our brain perceives the 3D bump on a surface mostly from information that it receives via skin stretching," said Ivan Poupyrev, head of the interaction research group in Pittsburgh.
To fool the brain into thinking it is touching a real feature, the vibrations imparted via the screen artificially stretch the skin on a fingertip so a bump is felt even though the touchscreen surface is smooth.
The researchers have developed an underlying algorithm that can be used to generate textures found on a wide variety of objects.
A video depicting the system in action shows people feeling apples, jellyfish, pineapples, a fossilised trilobite as well as the hills and valleys on a map.
The more pronounced the feature, the greater the vibration is needed to mimic its feel.
The vibration system should be more flexible than existing systems used to give tactile feedback on touchscreens, which typically used a library of canned effects, said Dr Israr.
"With our algorithm we do not have one or two effects, but a set of controls that make it possible to tune tactile effects to a specific visual artefact on the fly," he added.