Device structures of low coordinate distortion touch panel sensors using resistive films with electromagnetic wave shield effect have been investigated. The electromagnetic wave effect , optical transmittance and coordinate distortion characteristics were analyzed for sensors with ITO(Indium Tin Oxide) resistive transparent films. In results of these analysis, a device structure with two kinds of ITO films has been acquired. In the sensor, sheet resistivity of one ITO film is 10Ω, and ITO film of another side has 500Ω of sheet resistivity. Coordinate characteristics were analyzed by using of current continuous equation. By the analysis, electrode structures for low coordinate distortion characteristics have been obtained.

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Many lives and facilities were lost by fire. Especially, there are many damages to elderly, toddlers and babies. In Japan, number of deaths over 65 years old reached to 53% in 2004. Number of over 81 years olds went to 20%. It takes for the elderly person more time to sense fire and also to evacuate to safe places. Although it is important to prevent the fire, it also needs to inform the fire breaking as early as possible. Human sense decreases with age and it is difficult to perceive the fire at an early stage. It is desired to develop a higher sensitive element for fire and its system which can detect fire at an early stage. In this experiment, tin oxide gas sensors were adopted to detect a smoldering fire at the early stage. Most common case of fire is the smoldering fire. The reliability of the sensor is higher and it is adopted in a gas alarm detector. The sensor can also detect slight amount of odor molecule. In our previous experiment, it became obvious that it was better to install the sensor to the ceiling to detect odor components generating from smoldering fire. Therefore, five sensors were installed in the ceiling away from each other and the method to detect the fire was examined. As a result, a characteristic was newly derived by adding the sensor outputs for one minute. The sensor output was input every 0.1s. The characteristic is called as the integrated characteristic. After that, the differential characteristic was derived using the integrated characteristic. The fire was determined using the differential characteristics. The materials causing a smoldering fire were woodchip, wallpaper and carpet as subjects. The system could detect the fire in several minutes for whole materials. The sensor is effective to detect the smoldering fire at an early stage. It is necessary to detect a cigarette smoke to distinguish as non fire. In this study, the discrimination was also examined using a quadratic function (ax²+b). The coefficients a and b were effective to identify smoldering fire and cigarette smoke. Principal component analysis for the arrival speed S which meant a kind of odor-speed was also useful to distinguish fire from non fire.

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Recently, micro total analysis system (μ-TAS) utilizing micro-fabricated fluidic components has been extensively studied. In the field of μ-TAS, one of the important techniques is generation of gradients. The concentration gradient is utilized in various fields, such as analytical chemistry, optics, and biology. A number of techniques that generate concentration gradient in a micro-channel have been reported, which focus on generating concentration gradient in the “width” direction. However, in some applications, such as HPLC in analytical chemistry, generating concentration gradient in the “flow” direction is mandatory. In this study, we propose a micro-fluidic device that generates concentration gradient in the flow direction using diffusive mixing of droplets. The device generates and handles droplets using surface-modification of micro-channels by self-assembled-monolayer (SAM). We designed, fabricated, and experimentally evaluated the concentration gradient generating device. We successfully demonstrated generation of the concentration gradient of acetonitrile. The results indicated that the proposed micro-fluidic device is readily applicable to the fields of analytical chemistry and biology.

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An electrical-type distributed hydrogen sensor for detection of leak location has been proposed and evaluated. Platinum-supported tungsten trioxide (Pt/WO₃) was used as a hydrogen switch material whose electrical characteristics change from insulative to conductive with the exposure to hydrogen gas. This film was firstly coated on the glass substrate using sol-gel technique. Secondly, a couple of Al and Ni-Cr long interdigital electrodes were sputtered onto this film. The operation principle of this sensor is analogous to that of PSD (Position Sensitive Detector). If a part of line-type device is exposed to hydrogen gas, Al and Ni-Cr electrodes are short-circuited because Pt/WO₃ hydrogen switch of this point becomes on-state. Therefore, electrical resistance of long electrode is divided at this point and corresponding currents are detected. In our experiments, it was demonstrated that leak location could be determined with the ratio of the currents obtained from both ends as a sensor signal. The response speed was very fast and no influence of leak rate and distance from the device surface to the leakage point on steady-state sensor signal was observed. It is suggested that this method is suitable to detect the leak location of fuel cell equipments with lower-cost and ease.

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Mass-analysis scanning force microscopy is a kind of scanning force microscope (SFM) family, which equiped with a time-of-flight mass analyzer (TOF-MA). This microscopy will provide capability of surface imaging and chemical analysis, simultaneously. This letter presents microprobes with an electrostatic actuator to switch the measurement modes between surface imaging mode and mass analysis mode. Silicon cantilever, extranction electrode and electrosatic actuator with curved electrodes are fabricated on a Prexy glass. The cantilever is drived by stepwise pull-in phenomena. A large displacement of the cantilever can be obtained by the electrostatic actuation. Handling and releasing of latex beads are demonstrated using this probe.

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