Tetsuo Ohara

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and is made available as an electronic reprint (preprint) with permission of SPIE. One print or electronic copy may be made for personal use only. Systematic or multiple reproduction, distribution to multiple locations via electronic or other means, duplication of any material in the paper for a fee or commercial purposes, or modification are prohibited.(More)
This letter provides the first report of 160-Gb/s optical time-division-multiplexed transmission with all-channel independent modulation and all-channel simultaneous demultiplexing. By using a multiplexer and a demultiplexer based on periodically poled lithium niobate and semiconductor optical amplifier hybrid integrated planar lightwave circuits, 160-km(More)
W e propose new real-time position sensing devices with subnanometer precision. The precision level sought is in the range of 10egm to 10-12m with long range capability on the order of 8 12 inches. These devices will use either synthetic gratings or an atomic layer of a material, such as graphite, as the reference scales in conjunction with Scanning Probe(More)
INTRODUCTION Interpolation-error is the one of the most important performance parameters of precision encoders. We developed the modulated laser encoder which has high digital resolution (3.8pm) and low interpolation-errors [1]. In order to evaluate the interpolation errors, we introduced a unique error-measurement system using a tuning fork [2]. Advantages(More)
A prototype scanning tunneling microscope has been built in the Laboratory for Manufacturing and Productivity at MIT previous to this thesis work. The purpose of this thesis work is to improve the performance of the scanning tunneling microscope for other applications such as the surface modification in nanometer range. The scanning tunneling microscope has(More)
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