Recently, the idea of sustainable development is spreading rapidly from aggravation of the earth environment. Then, we can omit the useless when producing by doing the machine tool in the down-sizing under the idea of small parts processing using small machine, and responsible concern for the environment its requested. Additionally, the hard brittle materials used for optical components and electronic parts are produced by loose abrasive. However, loose abrasives process also creates a great burden on the environment. Thus it is necessary to replace this process with fixed abrasives with the idea of improving its shaping capability and alleviating environment problems. We draw attention to a five link micro machine. In the present report, it try to do polishing which trocoid movement in the plane of X-Y applying the kinetic characteristic of a five link micromachining for a hard brittle material, and to obtain the surface design equal with the separation rid processing because of the fixed grid processing.

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Thick films are needed in micro-electro-mechanical systems as insulation, piezoelectric and ferroelectric materials. To form the thick film, Powder Jet Deposition (PJD) method has been proposed. In the PJD process, particles are sprayed on the substrate under the condition of room temperature and atmospheric pressure. We have developed a new jet mechanism of double-nozzle type, and reported its results previously. In this study, we optimized the shape of the nozzle through investigate the influence of different dimensions and shape of the nozzle on the particle blasting velocity. As a result, it is found that nozzle diameter has a large affect on the particle velocity

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Electron element develops into high speed, high performance and high function, caused by the rapid development of the information technology. The wafer thickness of the electronic element becomes thin with performance. As that representative, the wafer becomes a big diameter, and moreover high precision, high quality and a low cost are demanded. It is difficult by the lapping of slurry to satisfy those requirements. A demand for the ultra-precision processing by grinding has been rising. We developed the fine diamond grains wheel of the new concept to. process Ultra-precision grinding. Therefore, it is reported about the Ultra-precision grinding that high precision is realized.

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The condition to finish up the optical glass (BK7) surface in mirror finish by grinding processing was examined. The flat grinding was done by using three kinds of precise grinders with several resinoid bonded diamond wheels. In the brittle materials such as the glass generated brittle fracture and cracks on the ground surface. It was found that the brittle fracture depends on depth of cut by traverse grinding with #1500 wheel. In order to reduce the brittle fracture by decreasing the grinding force, the flat grinding face of the diamond wheel was modified in a spherical shape. As a result, the surface roughness Ra 1nm and the flatness 0.4 μm was obtained.

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Recently, accuracy improvement of the molds is more and more required for the precise molding of aspherical glass lenses. These and moulds are mostly ground with micro diamond wheels, but require additional fmishing process such as polishing. In this study, ultrasonic two-axes vibration assisted polishing system with piezo-electric actuators was proposed and developed in order to apply to the high-precision and high-efficiency polishing of the aspherical molds and dies. From the experiments of the micro aspherical tungsten carbide molds, it is clarified that the newly developed two-axes vibration polishing method is useful for the efficient and precision polishing of micro aspherical molds.

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Optical and optoelectronic product such as digital cameras, mobile phone, and high-density optical disc systems use many optical lenses. Another attention-attracting trend is the development of compound glass lenses, namely, lenses that combine the refractive and diffractive functions of light. Compound lenses can consolidate the functions of two lenses into one. We developed the special Ni-alloy plated mold. This mold can be easily fabricated into diffractive patterns by cutting with a single-crystal diamond tool. In the present work, special Ni-alloy plated molds are applied to mold glass lenses. It is possible to mold a diffractive optical element (DOE) made of glass with special Ni-alloy plated molds. These molds have high-temperature strength sufficient to mold at 500℃ and can be applied to molds for high refractive index glass lenses.

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Tool condition is one of the essential factors for the machining of the micro-groove having high diffraction effect. Therefore, custom-designed diamond tools could be applied, which need some experience and skill for getting the fine surface. In this study, the high accurate and versatile machining method for micro rectangular groove was reported. This was aimed at rotational diffraction form and carried out by coordinated control of 2 linear axes and a rotary table. In the results, micro rectangular grooves less than 0.005mm and multi-step forms were obtained.

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Small sized aspherical Pt/C multilayer mirrors of 20 mm in diameter for hard X-ray imaging were made from ultra-precision electroless nickel dies by a molding method in order to inspect the optical imaging properties of next-generation hard X-ray telescope mirrors which will be made by a new technology. Electroless nickel is the key material for making large-sized molding dies of hard X-ray telescope mirrors because of its machinability and durability. Electroless nickel molding dies of parabolic and hyperbolic in revolution were obtained in the range of ±50 nm shape accuracy and less than 0.3 nm rms in surface roughness by single-point diamond turning and ultra-precision polishing. Pt/C multilayer aspheric inner mirrors were obtained from the electroless nickel molding dies by the special molding technique.

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An improvement of angular resolution is one of the most important problems in the development of high throughput X-ray telescope for future X-ray astronomy missions. We have developed a new method to make very thin mirror by diamond turning using special support structure made of water solvable UV-curing resin. One of a critical process to minimize the figure error is to control of internal strain. Using this method, we have made test conical mirrors with the diameter of 150 mm, the height of 100 mm, grazing angle of 0.6 degree and thickness of 0.3 mm. The mechanical design of this mirror and support structure, process of diamond machining including chucking and separation, and X-ray test for the mirror performance and their results are described.

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An electrical method for suppression of tool wear and improvement of finished surface texture was proposed in ultraprecision diamond turning of hard-to-cut materials. In face turning of carbon steel (SS400) with polycrystalline CVD diamond tool, electric voltage (10V) was applied between tool and workpiece. By this method the flank wear of the tool was reduced comparing to the case of normal (non-voltage) turning. As for the finished surface, craters formed by tearing action during cutting were remarkably reduced by the application of electric voltage, and the surface roughness became smaller. The improvement of finished surface texture by the application of electric voltage was also possible in face turning of carbon steel (SS400) with monocrystalline diamond tool.

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The mechanism of tool wear in machining of single-crystal silicon was studied because the service life of a diamond tool is normally very short. The cutting edge temperature was estimated by using the finite element method simulation. The tool wear mechanism might be related to the diamond deterioration by chemical reaction rather than by mechanical wear.

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Friction force and viscous resistance are yielded between driving parts of NC machine tools, and are changed by characteristic changes such as the change of lubrication conditions of driving components. Therefore, these affect the parameters for motion compensators. In this study, repeatability of quadrant glitches of feed drive systems was investigated. It is found from the results that height of quadrant glitch is changed by the friction force changes. In order to compensate the quadrant glitches repeatedly, torque-follow compensator was proposed. Corresponding to the friction force changes, the torque-follow compensator which compensates the difference between an ideal torque and an actual torque was newly developed. In this study, circular motion was simulated and measured with the compensator. It was confirmed that the proposed compensator can compensate the quadrant glitches repeatedly despite the friction force changes.

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