blue-c

Immersive VR Projection System with Simultaneous Image Acquisition using Active Projection Screens

The blue-c project was an internal research project of ETH Zurich with the goal to build collaborative, immersive virtual environments which integrate the representation of real humans as three-dimensional objects. The first of the two installations that were build is a three-sided spatially immersive back projection system. Sixteen cameras are integrated in this installation in order to capture the silhouette and texture of the user. A 3D-representation of the user is generated in real time and transferred to the remote installation, where it is combined with the virtual world and presented to the remote user. The remote user is also captured with sixteen cameras and his 3D-representation is transferred back to the first installation. The interconnected installations enable multiple users to interact and share applications simultaneously. The possibility to see the remote user in conjunction with the application gives a high sense of presence.

Four institutes were involved in the blue-c project. The ICVR was responsible for the hardware setups, namely the spatially immersive projection system and the image acquisition system. The main challenge associated with the hardware was to combine the projection with the image acquisition. In order to meet this challenge, electrically switchable "phase dispersed liquid crystal (PDLC)" glass panels were used as projection walls. The panels are switched to transparent for acquisition and opaque for projection. The switching is repeated 62.5 times per second. The cameras, which are located outside of the projection room, can acquire an image of the user through the PDLC glass panels during the transparent states. The active stereo projection system is only active when the glass panels are opaque.

The blue-c project was funded by ETH grant No. 0-23803-00 as an internal poly-project.