A thin ultrasonic motor which was originally developed for a calendar drive unit was further utilized for watch hands drive unit. Driving watch hands requires lower power consumption and shorter driving time compared to driving a calendar. The trajectory of the stator tip was modified by changing the phase difference between the two vibration modes, and contact angle of the stator with respect to the rotor was optimized to achieve lower power consumption and shorter driving time.

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Recently, nanoimprint technology becomes one of the attractive technologies to fabricate micro optical structures in mass production since their possibilities of low-cost and replicated production. In this paper, we study optical properties of diffractive optics and Fresnel lenses fabricated by our original nanoimprint machines. Furthermore, we build micro optical structures inside the liquid crystal active optics. Then we can control their optical properties by electrical signals and achieve good optical properties.

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The characteristics of cantilever are theoretically well known in the field of strength of materials. In case of analyzing behaviors of complicated mechanical structures, it is, in general, required to solve a lot of simultaneous equations derived from given equilibriums and constraints. In order to simplify equations mentioned above, the authors want to introduce a unique method in which only the cantilever theories are used. The method in which the cantilever theory and the principle of superposition are combined brings easily in results regarding to angular and translational displacement at any point of intricate mechanisms, by solving a few of simultaneous equations, the number of which is equal to arbitrary constraints of mechanism. The idea itself is not newly developed by the authors. The way shown here, however, surely seems to be peculiar and unconventional for analyses of complicated mechanical structures. After describing the beam theory on a cantilever, the principle of superposition and characteristics of the well known single leaf spring mechanism, the author theoretically analyze both angular and translational displacements of a newly developed double leaf spring mechanism and compare them with the results obtained numerically by FEM for designing the equipment. It is clarified from the theoretical and numerical results that the double leaf spring mechanism shows an excellent translational displacement with no angular displacement for fine positioning at the origin of the stage Based on theoretical and numerical analyses described above, the authors finally designed two modeled mechanisms, that is, one side supported double leaf spring mechanism and both side supported one. Both are much superior to single leaf spring mechanism from the view of structural balance and the distance to be traveled.

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We developed the performance prediction analysis techniques that aimed to improve the performance of mechanical watches. In this analysis, each part of watch mechanisms was modeled based on the motion equation of balance with hairspring. It is possible to forecast the Amplitude and the Daily rate by adding torque to the model. The output of the analysis provides enough evidence of usefulness by comparing with the actual measured data.

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We have commercialized outdoor watch series called "PROTREK" capable of measuring various information in the natural world by making good use of an advanced sensor technology. Since we only had a lineup of digital models, there were some voices in the market for an analog model which enables the better readability of sensor-measured information by using both dial indicator and hand location. In order to meet the needs, we developed our first ana-digi triple sensor watch with radio controlled and solar feature by maintaining the compact product design and by achieving the functions needed for outdoor use. This paper explains the technical summary of the development of PRW-5000 (Fig. 1).

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