Optical probes can measure specimen profiles under perfectly non-contact conditions, and have high vertical resolution. Therefore, optical probes are widely used for profile measurement. However, optical probes have the drawback of low lateral resolution. The lateral resolution of an optical probe depends on the spot size of the laser at the measurement point, and is generally one order of magnitude lower than the vertical resolution. This study proposes an optical probe with high lateral resolution by collecting laser irradiation. In addition, profile measurement simulations using a ray tracing method were performed. Simulation results confirmed that the displacement and tilt information of the specimen could be obtained from the outputs of the right and left optical probes. Furthermore, the results of profile measurement simulation showed that the lateral resolution in profile measurement can be improved by the proposed optical probe.

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The production volume of light-emitting diodes (LEDs), which are energy-saving products, is increasing to achieve low-carbon societies. Therefore, it is necessary to improve the productivity of sapphire wafers as substrates for LEDs. To improve the removal rate of chemical mechanical polishing (CMP) of sapphire substrate, we developed a high-efficiency method using ultrasonic vibration as mechanically assisted CMP and clarified its mechanism of action. This study confirmed the cavitation phenomenon in the vicinity of the substrate induced by ultrasonic vibration, and examined the effects of this phenomenon on the removal rate. Furthermore, the effects of ultrasonic vibration were verified using two types of suede-type polishing pad with different characteristics. The results indicated that in conventional CMP, the removal rate is increased by using a suede-type polishing pad with a large number of pores. In ultrasonic vibration-assisted CMP, the removal rate can be improved depending on the characteristics of the suede-type polishing pad.

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Electrodeposited grinding tools are characterized by a number of features, such as superior grinding efficiency and complex tool surface shape. These tools have comparatively high protrusion height, as the diamond abrasive or CBN grains are fixed on a base wheel by plating. The shape and the distribution of a single electroplated tool surface influence the grinding accuracy. Therefore, a method for measurement of diamond abrasive grain shape by image processing was proposed. The grain shape was shown to be uneven in one grade. Here, a method for classifying diamond abrasive grain shape by image processing is proposed. This method can determine the whole shape of the abrasive grains, and they can be divided into 14 classes. Finally, the relationship between the classification results and crushing strength was verified by experiment.

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