How Holographic Environments Will Work

­­ In the office of the future, you won't call people with a phone. You will com­mand your computer to call a particular person. "Computer, call Joe at the London office." Suddenly, one of your office walls will flicker and Joe will be sitting across from you as if he were right there. On the other end, Joe will experience the same immersive connection. That's the idea behind tele-immersion: bringing two or more distant people together in a single, simulated office setting. Business travel will be practically unnecessary.

This type of communication will take us beyond the limits of videoconferencing. Have you ever used a Webcam to teleconference with another person? If you have, then you've seen that videoconferencing via the Internet is not a perfect form of communication. The image is close to real-time, but there are delays that cause a jerking video. Also, if someone walks out of view of that one camera, you can no longer see the person. With tele-immersion, people can't walk out of the view of the camera. In fact, you can peer around their office just by looking at the display screen from different angles. It's like having a window to look through.

Holographic environments will be generated by computers with computing speeds thousands of times faster than your PC. There are several steps to constructing a holographic environment:

­ There are several groups working together on the National Tele-Immersion Initiative (NTII) to bring us all together in these virtual environments. In May 2000, researchers at the University of North Carolina (UNC), the University of Pennsylvania and Advanced Networks and Services reached a milestone in developing this technology. A user sitting in an office at UNC in Chapel Hill, NC, was able to see lifelike, three-dimensional images of colleagues hundreds of miles away, one in Philadelphia and the other in New York.

Tele-immersion may sound similar to virtual reality, but there are key differences between the two technologies. Virtual reality allows you to move in a computer-generated 3-D environment, but tele-immersion, for now, can only create a 3-D environment that you can see -- you can't interact in it. The next step is to merge tele-immersion and virtual reality to allow users to alter the scenes that they see.

The applications for immersive holographic environments are endless. Imagine a video game free of joysticks, in which you become a participant in the game, fighting monsters or scoring touchdowns. Instead of traveling hundreds of miles to visit your relatives for the holidays, you'll simply call them up and join them in a shared holographic room. Eventually, you will even be able to hug other people using this technology. Doctors and soldiers could use tele-immersion to train in a simulated environment.

The early prototypes of tele-immersive displays require users to wear special goggles and ­a head device that tracks the viewpoints of users looking at the screen. On the other end, the people that appear as 3-D images are being tracked with an array of seven ordinary video cameras, while two other video cameras capture real light patterns projected in each room to calculate distances. This enables the proper depth to be re-created on the screen. So, if a viewer moves his head to the right, he can see the corresponding images that would be seen if he were actually in the room with the person on the screen.

­Images on the screen are split and polarized to create a different image for each eye. The goggles then combine these images so that the brain recognizes only one 3-D image. This process is similar to how those old 3-D movie glasses work. Early experiments, like the one at UNC in May, have experienced some glitches, similar to those of normal video-conferencing. The scenes being projected are only refreshed three times per second, which creates a jerky image. If that rate could be improved to 10 frames per second, it would create a seamless projected image that would be like looking through a window at another person. Scientists are developing new technologies to support this type of communication, including:

­ Tele-immersion will blur the lines between real and computer-generated images. It will be the ultimate tele-commuting technology, almost entirely eliminating the rush-hour drive to work. Instead of commuting, people could attend board meetings by projecting themselves into the company's conference room. And if your job requires you to travel, you could still be home for dinner by tele-immersing yourself into the family kitchen. Because this technology is still in the early stages of development, the possibilities are truly endless.

For more information on holographic environments and related topics, check out the links that follow.