Windows to other places: exploring solutions for seeing through walls using handheld projection

Mobile projection offers an interesting technology for creating displays on any surface without a situated screen. In this paper, we investigate two concepts that use handheld projection to see to other places through a virtual window. Firstly, we present a projector phone based prototype which, when pointed to the walls of a room, reveals images and a video stream from the physical space on the other side of the wall. Secondly, a novel handheld dual-display virtual reality browser that opens a virtual window to a remote location is presented. This prototype combines two displays, a screen and a projected display. Both concepts were evaluated in user studies (n=22 and n=23). We report, for example, that mobile projector based browsing was considered more fun and inspiring than a screen and mouse format, and that the horizon level of the projected image should be kept horizontal when browsing.