is a mobile projector-based system that enables new
applications and interaction techniques with tangible objects
uses a device mounted camera to
detect hidden markers applied with infrared-absorbing ink.
The obtrusive appearance of fiducial markers is avoided and
the hidden marker surface doubles as a functional projection
surface. We present example applications that demonstrate
a wide range of interaction scenarios, including media navi-
gation tools, interactive storytelling applications, and mobile
games. We explore the design space enabled by the
system and describe the hidden marker prototyping process.
brings tangible objects to life for interaction with
the physical world around us.