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Information Display with an Afterimage by Laser Projection Moving Object


This is a new method to display information based on the afterimage of a moving object. Existing systems need a static surface on which information is projected. In contrast, we propose a new display system projecting laser on a moving object, and exploit the afterimage phenomenon to expand the projectable region. Human vision can recognize patterns larger than the size of the object due to the afterimage created in the region spanned by the moving object.

In order to realize the system, in other words to aim the laser beam on a specific position given by the object location with precise timing, the projector is integrated with a high-speed optical device, called Saccade Mirror. This device is originally designed to keep the camera gaze fixed at a dynamic target (cf. 1ms Auto Pan-Tilt ).

While the Saccade Mirror tracks a moving object, the projector is directed through the optical system of the Saccade Mirror. As a result the laser beam used to project on the desired location on the target, effectively shares the optical axis with the camera tracking the target.

Fig1. Outline of this method.
Fig2. Presentation on a moving ball.
Fig3. Connection of the Laser Module and the Saccade Mirror.


  • Kohei Okumura, Hiromasa Oku and Masatoshi Ishikawa: High-Speed Gaze Controller for Millisecond-order Pan/tilt Camera, 2011 IEEE International Conference on Robotics and Automation (ICRA 2011) (Shanghai, 2011.5.12) / Conference Proceedings, pp.6186-6191
Ishikawa Watanabe Laboratory, Department of Information Physics and Computing, Department of Creative Informatics,
Graduate School of Information Science and Technology, University of Tokyo
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