We propose a novel fabrication process for twin probes of an atomic force microscope (AFM) that consist of a silicon dual tip with a narrow gap. The dual tip with a tetrahedral shape consists of an inclined silicon (111) plane and two vertical planes and was successfully fabricated by using the proposed fabrication process of combining deep reactive ion etching (D-RIE) for silicon trench formation along the silicon (001) direction, selective oxidation of the sidewalls of the trench, and crystalline anisotropic etching. The silicon tips could be sharpened by a low-temperature oxidation process, resulting in a tip radius of about 10 nm. In addition, the dual silicon tip formation, dual AFM probe with cantilever, and thermal actuator were also successfully fabricated from a silicon-on-insulator (SOI) water. The gap of the dual tip was about 2.9 µm, with trench etching 1 µm wide and sidewall oxidation 1 µm thick.
This paper describes a new networked telepresence system which realizes virtual tours into a visualized dynamic real world without significant time delay. Our system is realized by the following three steps: (1) video-rate omnidirectional image acquisition, (2) transportation of an omnidirectional video stream via internet, and (3) real-time view-dependent perspective image generation from the omnidirectional video stream. Our system is applicable to real-time telepresence in the situation where the real world to be seen is far from an observation site, because the time delay from the change of user’s viewing direction to the change of displayed image is small and does not depend on the actual distance between both sites. Moreover, multiple users can look around from a single viewpoint in a visualized dynamic real world in different directions at the same time. In experiments, we have proved that the proposed system is useful for internet telepresence.