Biomagnetic field measurement is widely used the magnetic field perpendicular to the scalp. There are problems of separating multiple sources overlapping in time when many distinct areas are active. We developed a three-dimensional (3-D) second-order gradiometer connected to three SQUIDs for vector measurement of the MEG (magnetoencephalogram). This SQUID magnetometer can detect magnetic field components perpendicular (Br) and tangential (Bθ, Bφ) to the scalp simultaneously. Magnetic field distribution of tangential component can provide information about new constraint conditions for inverse problem by visual inspection. This paper presents example of a 3-D vector measurement of MEG.

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A very low-temperature process for preparation of functional oxide thin films is newly proposed and examined by sol-gel-hydrothermal combined treatment. A series of oxide ferroelectric thin films have been prepared by the method in various mineralizer, alkaline solutions. Especially PZT film grown in KOH+Pb(OH)₂ solution at final post-baking temperature as low as 400°C, showed a well-saturated, good P-E hysteresis loop with Pr=26.3μC/cm² and Ec=40.1 kV/cm, respectively.

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Concepts of highly bright electron source for beam systems such as electron microscopes and electron exposure systems are given. Recent progress in developing thermal field electron source is reviewed. It is shown that work function of W(100) surface is selectively reduced by modifying the surface with yttrium and with oxygen. The reduced work function is 2.1 eV, which is about 0.6 eV smaller compared with ZrO/W(100) thermal field emitter. It is also shown that the work function of Molybdenum is also reduced on (100) surface selectively by modifying the surface with zirconium and with oxygen. The reduced work function is 2.0eV. Potential abilities of field emission arrays and carbon nano-tubes for electron sources are critically shown.

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We have developed micro mechanical variable optical attenuators (VOA) using an electrostatic micro torsion mirror combined with fiber-optic collimators. For the sake of high productivity and high mechanical reliability, we have designed ASymmetricaly driven Parallel plate (ASP) Tilt Mirror (TM). The structure of ASP-type TM is very simple and it can be made by using bulk micromachining of SOI wafer. As a result, we have successfully downsized the VOA package to 5.6 mm in diameter and 23 mm in length. Optical performance is excellent for the optical communication network, small insertion loss of 0.8 dB and polarization dependent loss of 0.2 dB have been obtained.

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In this paper, a practical sensing approach for monitoring the liquid-level in a container is presented. In this research we have developed a new structure sensor with three electrodes. When the container becomes inclined from vertical condition during measuring process, the liquid-level in the liquid container is determined correctly by detecting the change in capacitance between every two electrodes. In this process, a multidimensional regression equation based on experiment data is adopted. The result of this research proves that the designed sensor can be used to measure the liquid-level in the container unrelated to inclination.

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