Tele-Immersion is a new medium that enables a user to share a virtual space with remote participants. The user is immersed in a 3D world that is transmitted from a remote site. This medium for human interaction, enabled by digital technology, approximates the illusion that a person is in the same physical space as others, even though they may be thousands of miles distant. It combines the display and interaction techniques of virtual reality with new computer-vision technologies. Thus with the aid of this new technology, users at geographically distributed sites can collaborate in real time in a shared, simulated, hybrid environment submerging in one another's presence and feel as if they are sharing the same physical space.

It is the ultimate synthesis of media technologies:
1.3D environment scanning,
2.projective and display technologies,
3.tracking technologies,
4.audio technologies,
5.robotics and haptics, and powerful networking. The considerable requirements for tele-immersion system, make it one of the most challenging net applications.

In a tele-immersive environment computers recognize the presence and movements of individuals and objects, track those individuals and images, and then permit them to be projected in realistic, multiple, geographically distributed immersive environments on stereo-immersive surfaces. This requires sampling and resynthesis of the physical environment as well as the users' faces and bodies, which is a new challenge that will move the range of emerging technologies, such as scene depth extraction and warp rendering, to the next level.