<title>Haptic interaction with holographic video images</title>

We describe the implementation of a system which enables a user to interact with and modify an electronic holographic image using a force-feedback device. The force-feedback (or haptic) device is capable of sensing and reporting the 3D position of its hand-held stylus and displaying appropriate forces to the user. Thus, a user can feel and modify algorithmically specified shapes in the haptic workspace. We precisely register the haptic workspace with the free- standing, spatial image displayed by the MIT second-generate holographic video system (holovideo). In the coincident visuo-haptic workspace, a user can see, feel, and interact with synthetic objects that exhibit many of the properties one expects of real ones, and the spatial display enables synthetic objects to become a part of the user's manipulatory space. To the best of the authors' knowledge, this is the first time that such an interactive holographic system has been built.