High performance and miniaturization are strongly demanded for optical elements and precision parts, where microgrooves play an important role. A non-rotational cutting tool is one of machining means to create microgrooves. However, even non-rotational cutting tool forms slopes at the cutting start and end points, which deteriorate the optical performance. In optical elements and precision parts, the creation of two flat-ends microgroove is expected, where two flat-ends microgrooves mean microgrooves having no slopes at the cutting start and end points. The method to create two flat-ends microgroove has already been devised and applied for soft materials, not for hard materials. In the study, a new method is proposed to create straight and curved microgrooves with two flat-ends for hard materials by indenting and feeding a non-rotational cutting tool. From experimental results, it is found that the proposed method has the potential of creating two flat-ends microgrooves for hard materials.

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The measurement of cutting force is important to monitor the status of the process during micro drilling. It is used the cutting dynamometer, the shape of the workpiece is restricted and must be set to the center. These problems can be resolved by adoption of the spindle with built-in sensor. The purpose of this study is the development of the sensor built-in spindle for micro drilling that the thrust and the torque can be measured simultaneously. The structure of the spindle uses a static pressure bearing and a capacitance sensor to realize high accuracy measurement. As a result of study, this spindle was able to measure very weak thrust and torque to occur by micro drilling of 0.05mm in diameter. These results of research can be constructed the advanced processing system which prevents the breakage of the drill by monitoring the cutting force.

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NC commands are generated by CAM systems to realize high speed and high accuracy machining. At the time, the feed rate in most of NC data may be set to be constant in machining any workpiece shapes. In addition, NC data do not necessarily reflect the workpiece shape correctly due to the variation in the coordinate point values calculated by CAM systems. It causes the reduction in the machined surface quality. The shape recognition in the tool feed direction on the basis of NC data has already been devised. Thus, the study enables 3-D shape recognition to be identified from NC data in the pick feed direction as well as those in the feed direction. After the identification, the feed rate can be controlled according to the identified shape information. The system developed in the study can detect the distinguishing points from the coordinate information in NC data. Then, the points are arranged to generate the smooth tool motion and to control the feed rate for the identified workpiece shape. From experimental result, it is confirmed that the machined surface quality is successfully improved and the machining time is also reduced.

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The effect of weld-line reduction by using the laser metal sintered mold and the effect of hot air supply on the mold surface just before the injection have been investigated. The depth of the weld-line groove in the laser metal sintered mold is smaller than that in the conventional steel mold. Mold pressure increase in the laser metal sintered mold is faster than that in the steel mold and the peak pressure in the laser metal sintered mold is higher than that in the steel mold. This must be due to the low thermal conductivity of the laser metal sintered mold. As a preheating effect of the mold surface before the injection, hot air has been supplied on the mold surface using an air jet bulb. The reduction of the weld-line groove has been promoted in the laser metal sintered mold whereas few effects appeared in the steel mold. Surface temperature increase by the hot air supply in the laser metal sintered mold is larger than that in the steel mold. By this higher temperature increase, temperature of the resin on the weld-line area must be higher and the hardness of the resin must be lower in the laser metal sintered mold so that the resin is deformed well reducing the weld-line groove.

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Cerium Oxide (CeO₂) slurry is frequently used for making high precision surface finishes of glass substrate applied for Hard Disk Drive (HDD) and Flat Display (FD). However, CeO₂ is one of the rare metals. Therefore, both reduction of supply amount of CeO₂ slurry and development of new slurry without CeO₂ need to be improved. This paper presents the optimum CMP conditions applying CeO₂ slurry as a parameter of slurry concentration, polishing pressure and platen rotational speed. Moreover, we discuss the advantages of Manganese Oxide (Mn₂O₃) abrasive for replacing CeO₂ abrasive. In the result, it is found experimentally that the proposed conditions are efficient in reduction of CeO₂ abrasive. Moreover, Mn₂O₃ abrasive indicates optimum performance for the polishing of glass substrates.

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In milling with a ball end mill using a 5-axis machining center, the attitude of tool or workpiece is controlled by tilting two axes, therefore allowing milling to be performed by a cutting edge of an outer portion, which has a large cutting speed. However, the effects of the tool tilting angle on the cutting forces, tool deflection and machining error have not been clearly identified. In this 1st report, geometric quantities such as the tool-workpiece contact region, undeformed chip thickness along the cutting edge and the area of cutting cross-section, and the cutting speed in slot milling with tool tilted by one or two axes are analyzed, and variations of these quantities with the tool tilting angle are discussed. A cutting model proposed in previous papers, in which a cutting edge of both a spherical portion and a cylindrical portion engage with the workpiece, is applied to the above milling process. Cutting forces in various tool tilting angles are predicted, and compared with experimental results. Predicted results are in good agreement with experimental results. It is found that when a large positive angle is specified for each of the tool tilting angles, the variation of cutting forces in milling decreases, and it also becomes possible to obtain a large cutting speed.

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Large quartz masks require a flatness tolerance of 10 μm to transfer fine patterns; however, these masks typically have a warp range of 10 to 100 μm. Fabricating a nonwarped mask is difficult because, during the polishing process, the mask substrate cannot be held without deformation. Therefore, a nondeforming freezing pin chuck has been developed. This paper describes a new application method and the resulting characteristics of the freezing liquid droplets. An oil-repellent coating and a newly developed low-speed spraying method were used to make a spherical droplet on a pin. The evaporation times of freezing liquid and water droplets on a 0.5-mm-diameter pin are the same (about 200 sec) despite the difference in volume, because the water droplet has a significantly larger surface area. After the oil-repellent coating was applied, the contact angle of the freezing liquid droplet increased from about 40° to about 120°, and the height increased from 65 to over 300 μm; likewise, the contact angle of the water droplet increased from about 130° to about 160°, and the height increased from 400 to over 1000 μm. When combined with the oil-repellent coating, the new low-speed spraying method yielded a freezing liquid droplet with a height of over 200 μm on a 0.5-mm-diameter pin — more than three times the height generated before the oil-repellent coating was applied.

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The probe with a 110-millimeter diameter is fabricated for measuring accuracies of extremely deep holes. It consists of a measurement unit, skid unit and a laser diode, which are used to detect the position and inclination of the probe. Measurement unit, which is mounted on the forward part of the probe, is equipped with a pentaprism and a stylus with a corner cube prism. The hole shape is detected by measuring movement of a stylus perpendicular to the hole wall using a laser interferometer. The laser interferometer is set in front of the probe. Its laser beam is radiated toward the pentaprism of the measurement unit and deflected toward the corner cube prism. The beam reflected from the corner cube prism reaches the interferometer via the pentaprism. In the present study, a probe is fabricated using skids instead of piezoelectric actuators and its performance is examined. The use of skids reduces the production cost because they are less expensive as compared to piezoelectric actuators. The results show that roundness and straightness of a deep hole measured by the probe correspond well with those by an electric micrometer and a roundness tester when measuring the gradually changing hole wall.

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