In this report, a trial of the evaluation of aspherical lens using phase shift shearing interferometer with plane parallel plate are discussed. Shearing interferometry is a measuring method by interference between a wave front under test and itself but sheared slightly. The method is robust to disturbances because it is a common path interferometry. Moreover it is not necessary to prepare reference surface. Therefore it can be said that it is a practical measuring method.

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A phase-shifting point diffraction interferometer (PS/PDI) with two optical fibers has been developed for absolute surface figure measurement of large aperture optics. Diffracted spherical wave from point light source is used for standard surface in a PS/PDI. A PS/PDI is appropriate for surface figure measurement of concave mirror. Absolute aspherical mirror measurement is needed. Surface figure measurement of parabolic mirror has been studied as aspherical measurement.

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Temporal carrier technology is introduced to electronic speckle interferometry in order to produce virtual speckle patterns. Then, dynamic deformation measurement with a large deformation is performed by using virtual speckle pattern. However, in this method, it takes a long calculating time to make virtual speckle patterns, because the temporal carrier analysis is performed in each pixel of CCD. In this proposed method, virtual speckle patterns are produced without temporal carrier analysis. Then, Carre algorithm is employed. As the results, the calculating cost is improved remarkably and the high measurement accuracy is realized.

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Laser light scattering is commonly used for surface-defect inspections in nanofabrication processes such as the manufacture of semiconductors and hard disks. In this paper, convex/concave discrimination of nano-scale defects on surfaces utilizing laser light scattering is described. Angular distribution of scatter intensity is analyzed for common silicon wafer surface defects (particles, crystal originated particles, and microscratches) using Discrete Dipole Approximation simulation. We show an example of a new method for convex/concave defect discrimination that utilizes angular distribution in both the azimuthal and elevational directions on the basis of calculated defect scatter characteristics. The results of our evaluation show that discrimination accuracy improves compared with the conventional method that utilizes angular intensity distribution only in the elevational direction.

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Observation method for contact state of solid surface such as the metal object is proposed. The method is based on the total internal reflection of prism. Elastic layer between the prism and the test surface enlarges the contact area. High polymer sheet or textured material is used as the elastic layer. Depth distribution of the surface is estimated from the observed contact pattern. The depth rang from several micrometer to above a hundred micrometer is adjusted by the sheet thickness or applied load.

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A lot of reports have been proposed on pattern projection methods and nowadays these have been reached to practical applications. However, the problem has been issued that the pattern using a conventional projection method inclines the standard plane on the projected surface. Until now, our group has been developed a digital device using a liquid crystal and achieved fast-three dimensional measurement. We report to solve the countermeasure of this problem by projecting a deformed grating.

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Our group has studied an inner profile measuring method using a ring beam device which consists of a conical mirror and a laser diode. Using this instrument, we can measure the inner surface profile of a cylindrical shape with non-contact and fast speed. We will show a new instrument which became more compact than the 1st report as demonstration. Moreover, we will show the evaluation results of the conical mirror using a diffraction technique. In addition of these results, we will discuss geometrical considerations from the measured profile of sample.

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We are aiming to apply the imaging-type 2-D Fourier spectroscopy into unstructured environment. The imaging-type 2-D Fourier spectroscopy is the phase-shift interferometry between the objective rays without the reference lights. Therefore, this proposed spectroscopy can be constructed only with reflective optics without the half mirror. In this report, we mention the configuration of the spectroscopic telescope for 2-D spectroscopic imaging of astronomical body.

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We proposed the imaging type 2-D Fourier spectroscopy that is the phase-shift interferometry between the objective lights. The proposed method can measure the 2D spectral image at the limited depth. Because of the imaging optical system, the 2D spectral images can be measured in high spatial resolution. In this report, we mention about the improvement of the optical system for spectroscopic tomography in infrared region.

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Burst acoustic emission waves were detected during single pulse discharge. Behavior of burst acoustic emission wave depends on cavitations behavior. In this study, air, oil and glycerin were applied as gap region medium. Acoustic emission wave was detected by optical fiber vibration sensor that was not affect on electrical magnetic noise. As the results, burst acoustic emission wave was detected only at once in air and glycerin discharge. On the other hands, burst acoustic emission wave were detected several times in oil discharge.

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This report deals with the machining performance of electro-chemical discharge machining (ECDM) with multiple electrodes. Holes were machined by ECDM on glass. The forced discharge current was observed during the machining process. Its machining performance was compared with those with multiple electrodes connected electrically in parallel (equi-potential) and a single electrode. A current with a duration of several milliseconds preceded a series of sharp pulses below 200 μs in the single electrode and divided power method. Long and low peak current pulses occurred in the equi-potential method.

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In wire EDM using a fine wire electrode, uniform distribution of spark location is necessary to achieve the high-performance machining. Branched electric current method has been conventionally used for evaluating the distribution of spark location. However, when the workpiece thickness is very thin, it is difficult to evaluate precisely the distribution of spark location by the conventional method. In this study, a new evaluation method by a using high-speed video camera is proposed. The positions of discharge are analyzed using the recorded high-speed images during machining. Then the effects of wire tension and wire running speed on the distribution of spark location are investigated by the new method.

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In wire EDM, better exclusion of debris and bubbles from the working gap is important to obtain stable electrical discharges and high-performance wire EDM characteristics. However, the flow field of working fluid in the gap has not yet been made clear sufficiently. The purpose of this study is to clarify the fluid flow and to recommend better conditions for jet flushing of working fluid from the nozzles by CFD (Computational Fluid Dynamics). In the previous report, the effects of wire running speed and the workpiece thickness were discussed. In this report, the effects of working fluid jet flushing conditions from nozzles such as flow rate and nozzles gap distance on the flow field and debris exclusion were investigated.

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In order to elucidate the origin of the space and the earth, it is demanded that a part of rocks showing above the surface is sampled and its inside is inspected on moons, planets or comets. In this report, cutting characteristics of rocks in air and vacuum were investigated for the preprocess of the scientific inspection. Basalt was cut with a saw wire reciprocated. The machining amount was proportional to the number of the wire reciprocation in air. However, the machining amount in vacuum was saturated in a short time. The electrification by the fracture of the rock caused loading on the saw wire.

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