As television and the Internet meld together, interactions with the screen promise to get more awkward. Touch-screen might be handy on a smart phone, but pawing at a giant flatscreen TV is less than ideal.
Researchers in South Korea recently unveiled a prototype remote that can put your thumb in two places at once.
"After trying different options our final conclusion was we have to build our own touchpad that can track fingers even when they are not in touch with the surface -- and that's fast enough to produce effective visual feedback on the TV screen," said Geehyuk Lee, an associate professor in the Human Computer Interaction Lab at the Korean Advanced Institute of Science and Technology (KAIST) who worked on the prototype.
The resulting device produces a shadow of the user's thumb on the screen. Touch the remote or even hover a thumb slightly above it, and the shadow on the screen responds accordingly.
The optical touchpad contains a two-dimensional array of LEDs that turn on one at a time in sequence, making its power consumption low. The 25-by-35 millimeter LED matrix takes a "proximity" image of a thumb hovering over it 50 times a second. A mechanical switch provides high-fidelity haptic feedback. The technology was created in collaboration with KAIST Department of Industrial Design associate professor Woohun Lee and several masters students.
"There was no optical touchpad that is that small and can track fingers as far as 10 millimeters away from the surface," Lee said. RemoteTouch is the first optical touchpad with this kind of hovering capability.
The researchers felt that existing tech involved too much work. The viewer has to move a whole arm, move the device around, or put the remote on a flat surface so it works. To limit the needed motion, the team decided to use one-to-one mapping between the touchpad and the TV screen.
The KAIST researchers compare RemoteTouch to two similar technologies: Panasonic's EZ Touch Remote and Tactiva's TactaPad. Unlike their prototype, Lee said the EZ Touch doesn't have hover tracking. The TactaPad uses a camera above the surface to take a picture of the user's hand and was designed to be used for desktop computing not TV control, he said.
"RemoteTouch will become more and more useful," Lee said. "We may need to select a song from a very long list, or select a music album from a coverflow. All those things can be done in a pleasant manner."
The technology was presented last week at the ACM CHI Conference on Human Factors in Computing Systems in Vancouver. The researchers wrote in their paper for CHI that one of the disadvantages to absolute position control -- versus the relative positioning in traditional touchpads -- is a more unstable cursor. University students who tested RemoteTouch reported little hand fatigue and fast visual feedback but experienced some frustration with the thumb shadow placement.
The next step for the team will be to develop a process to manufacture the device inexpensively. They are working with a large manufacturing company on a new higher-quality prototype that should be ready for testing in two or three months, Lee said.
Stacey Scott is an assistant professor in the department of systems design engineering at the University of Waterloo with experience developing media control technology. She said RemoteTouch has potential, as well as unresolved challenges.
One is that the RemoteTouch screenpad is a miniature map of the TV. "You're trying to map a small, small location on the screenpad," Scott said. "I think it's really tricky."
Still, she found the innovation interesting. "I like that idea that they're visualizing on the TV because it makes it a more publicly accessible interface," she said. "You can at least get feedback: 'No, no, no -- go over there!'"