Recently, the demand on position detection system using WiFi[1] and cellular phone[2] have been appeared. Car navigation system and 3G cellular phone use GPS(Global Positioning System) for position detection. However, it is impossible to use GPS underground because GPS signal cannot be received due to obstacles. Therefore, many position detection methods to use at narrow area have been proposed...

A high-speed position detector has wide variety of application fields such as real-time range finding and high-speed visual feedback in robot vision. In this paper, a row-parallel sensor architecture for high-speed position detection is presented. The edge of activated pixels is quickly detected by a row-parallel search circuit and its encoding cycles of Npixel horizontal resolution are O(log N...

We experimentally demonstrate a nonimaging approach to displacement measurement for complex scattering materials. By spatially controlling the wavefront of the light that incidents on the material, we concentrate the scattered light in a focus on a designated position. This wavefront acts as a unique optical fingerprint that enables precise position detection of the illuminated material by simp...