Attendees at the Conference on Human Factors in Computer Systems (CHI) this week saw a device that looks something like a lamp shade and houses a projector and camera, designed to let a worker share a physical desktop with another, allowing the two to collaborate on a project in ways not otherwise possible.
In one example at the show, two attendees were able to draw a picture of a house, with a pen and paper, simultaneously with each person adding different components. On one side, IllumiShare, a project from Microsoft Research, used a camera to capture the desktop and a projector to display the other side's. That means that each person received real time video of what the other side was doing.
To see IllumiShare in action, watch a video on YouTube.
That also presents the problem of video feedback. If left uncorrected, the projected and captured images would cycle in an endless loop, making it impossible to work. Researchers solved that by making sure the camera and projector were both never on at the same time.
"To time multiplex the camera and projector and not see visible flicker we need to do that at 60 hertz," said Sasa Junuzovic, a researcher at Microsoft Research. "What we need to do is simulate 120 hertz where it is going to alternate back and forth."
Switching between the camera and projector created another problem though. By "stealing time" from the projector the projected image won't be bright enough to see. Junuzovic calculated that he could only steal about four milliseconds.
"In our current setup, and because we basically have a webcam, we cannot take a really good image with only four milliseconds of shutter time," he said.
So he added an LED array inside the lamp shade that acts like a camera flash.
"It's off when the projector is on so it doesn't drown out the image and it's on when the camera comes on," he said.
The complicated setup let show attendees play card games, tic-tac-toe with pen and paper and trace each other's hands, but Junuzovic envisions the project to be much more than a toy. He said he plans to build 40 units and send them to Microsoft offices worldwide to see how developers and designers can collaborate.
"They won't have to travel from office to office, building to building or even floor to floor," he said.
The two IllumiShare stations at the CHI conference were on a local network, but Junuzovic said that dependent on bandwidth they could work on Skype.