In order to obtain highly pure red emission, the authors prepared organic light-emitting-diodes (LEDs) with a squarylium (Sq)-doped aluminum quinoline (Alq3) emission layer. We discussed their electroluminescence (EL) and electrical properties. The EL from Sq had a peak wavelength of _??_680nm and a half-width of _??_30nm. Only the EL from Sq (purely red) could be observed at the doping concentration of >14mol%, but the luminance was low (a few cd/m²) and unpractical. Although Sq molecules are thought to act as trap site in Alq3 molecules, they are concluded to act as hopping site at doping concentration of >7mol%. When Al-Li alloy with lower work function than Al is used as a cathode, the EL efficiency of Sq-doped Alq3 LED was not improved in spite of that of undoped Alq3 LED enhanced seven times. Therefore, the EL mechanism of organic Sq-doped Alq3 LED cannot be explained by simple carrier trap and energy transfer models.

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The authors investigated the EL properties of the organic light-emitting-diode (OLED) with a distyryltriphenylamine derivative (MDTPA). Although, PL and EL of MDTPA thin film was in blue region, the EL of indium-tin-oxide (ITO)/MDTPA/aluminum quinoline (Alq3)/Al was due to the emission from Alq3, but not the emission from MDTPA. It can be explained by that the emitting region is formed in Alq3 layer since MDTPA has excellent hole transportation. The authors introduced an oxadiazole dimer as carrier blocking layer between MDTPA and Alq3 layers in order to form the emitting region in MDTPA layer. This OLED was found to have a high performance for a blue-light-emitting EL device. Its luminance was over 3000cdm^-2 at the current density of 100mAcm^-2. The EL threshold voltage was about 5 V. Using AILi alloy as the cathode instead of Al, the OLED had higher performance.

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Two-dimensional trajectory analysis of a point mass circular movement gyroscope, fabrication of a macro model of the gyroscope, and measurement of its characteristics, have been carried out. The gyroscope consists of a point mass on the tip of a pillar which moves in a circle, and sensors which detect displacement of the point mass caused by Coriolis force. The trajectory of the point mass was indicated in an oval shape, which was symmetry to an axis, an external rotation rate applied. Deviation from circular trajectory of the point mass was indicated as a function of external rotation rates applied around the X-axis ω_X and the Y-axis ω_Y and of a time t. In the macro model, the point mass was given a steady circular movement by electromagnetic actuators. Displacement of the point mass caused by Coriolis force was detected with piezoelectric sensors which were attached to a beam supporting the pillar. Resonant frequencies of the X-axis and the Y-axis were 130 Hz±4 Hz. An output sensitivity of 4.2mV/p-p to 2.5deg/s was obtained.

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In recent years there has been growing commercialization of small size devices. The present work describes the method of three-dimensional measuring for small parts by low contact force. Small touch probe consists of quartz sphere (φ0.125mm), stylus (ength 2mm, φ0.lmm), cross sheet (thickness 0.01mm, width 1.25mm) and optical displacement sensor. Touch probe was able to detect the coordinate from transformation of cross sheet center, which was generated at the contact point. Probe touched the object surface, and x, y and z numerical values were obtained. Being employed ring gage, as test specimens, the standard deviation was 1μm.

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