This paper introduces objectives and status of “Human sensing fusion project” in the Exploratory Research for Advanced Technology (ERATO) scheme produced by Japan Science and Technology Agency (JST). This project was started in December 2007 and the laboratory with 11 members opened on April 2008. The aim of this project is to realize a human activity-monitoring device with many kinds of sensors in ultimate small size so that the device can be pasted or patched to the human body, and to establish the algorism for understanding human condition including both physical and mental conditions from obtained data. This system can be used towards the prevention of the danger of accidents and the maintenance of health. The actual research has just begun and preparations for project are well under way.

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New approaches of image interpolation are proposed to compensate for the discontinuity after correcting the barrel distortion and longitudinal chromatic aberration derived from the embedded digital camera in cell phone. This method determines the value of a lost pixel by the texture around the pixel which can be classified into 16 cases and then interpolate the pixel by nearest neighbor, linear interpolation or bilinear interpolation according to the specific case. That is why we named it case analysis interpolation. The proposed method needs interpolation only once. Visual and quantitative comparisons of the interpolation results of five kinds of texture suggest that the proposed algorithm outperforms others in most of the textures, yielding the smoothest interpolated result.

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Reactivity between nanoimprint mold material and optical glass has been investigated by measuring the contact angle between these materials in a nitrogen atmosphere at high temperature up to 1000°C. Since the low softening temperature optical glass was chosen in this study, the thermal upper limit of the contact angle measurement was set 800°C on. As the mold materials, electrodeposits Ni-W alloy containing 40 wt% W and the glass like carbon (GC) were chose. In the case of the GC, the contact angle did not changed largely at the temperatures up to 800°C, while obvious reactant phase in the interface layer between GC and the molten glass was observed. In the case of the Ni-W alloy, the contact angle decreased with increasing the temperature while, no reactant phase was observed at the interface. This indicated that indicating the Ni-W alloy is suitable as the mold materials for the B₂O₃-La₂O₃ based optical glass.

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The mechanical contact type potentiometer that has been conventionally used as a position sensor, is pointed out the problems of contact reliability, life time, and so on. Therefore, we are developing the non-contact magnetic type linear position sensor using impedance change according to the displacement.
In this paper, we evaluate AC magnetization characteristic of the core material used for a sensor, and investigate how to use complex magnetic permeability in the three-dimensional finite element analysis. In addition, the impedance characteristic of the non-contact magnetic type position sensor is calculated using the measured complex magnetic permeability of the core. As a result, we obtained the validity of the method that compares the measurements of the prototype to calculated value.

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We have developed a new Si DRIE process, which allows simultaneous etching of both narrow and wide mask opening patterns. MEMS devices often contains a wide range of mask opening sizes from μm to mm on a same chip. Conventional DRIE process suffered from a trade off between minimizing mask-undercut for narrow grooves and eliminating ‘Black Si’ on an etched bottom surface for large mask apertures. This was caused by non-uniformity in deposition of protective polymeric layer during etching among mask aperture areas having different sizes. Our new DRIE process technique alternating the conventional DRIE and O₂ plasma irradiation, adds SiO₂ layer onto polymeric layer. We have clarified that the new DRIE process can form SiO₂ protective layer having uniform thickness regardless of the mask aperture size. This uniformity is considered as a result of equilibrium between surface oxidation and sputtering of oxygen by plasma irradiation. We proved that our developed process allows a simultaneous etching of narrow deep grooves of 1μm width, 73μm deep, and wide aperture area of 500μm square without Black Si on a same chip.

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