This paper presents a new differential method named mixed-method, which is combined with the laser autocollimation and 2-point method. This method is developed to measure the profile accurately under the circumstance of on-machine measurement where large datum errors are introduced by scanning stage, vibration and thermal drift. An optical sensor using parallel beams with incident angle of 45° was designed and made to realize the mixed-method. Estimating from the SN ratio, the sensor can measure the displacement and angle of two points on a mirror surface simultaneously with the resolution of 0.1 μm and 1 second. Experiments with the sensor have shown that it can reduce datum errors by 30 dB. Using this sensor, measurements of the profile of flat mirrors and the straightness of cylindrical mirrors have been tried and effectiveness of the method especially for detection of high spatial frequency of profiles has been confirmed.

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Aspherical plastic lenses for laser apparatus need submicron accuracy in the shape profile of injection molded parts. In the molding process, polymer changes from molten state to glassy state, and the cooling history of each point is different. These phenomena causes irregular shrinkage deformation. Usually, the mold shape is corrected overall using a constant shrinkage ratio. So it is difficult to develop highly shape accurate molded parts. In order to obtain better shape accuracy, shrinkage amounts must be computed exactly and the shape of mold must be corrected. Shrinkage amounts are computed from shape difference between the mold's shape and the shape of trial molded parts. The shapes of mold and molded parts are computed from regression of measuring data. This paper describes the shape regression algorithm, the correcting algorithm of mold, and the application of this method to aspherical lens's molds. Experiment shows that plastic lenses with a shape error of less than 0.3μm can be molded.

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Geometric modeling systems must have a variety of capabilities to describe products' shapes, because machine functionalities are realized by its geometric features. However, conventional geometric modeling systems are not powerful and flexible enough for handling those features of products in design and manufacturing processes. In order to cope with this problem, basic interface for geometric modeling systems using generalized topology and geometry is proposed in this paper. The interface provides functionalities for handling several types of topology models, such as solids, surfaces, and wireframe edges. A non-manifold data structure based on neighborhood relationships is used for integrating those topology models. The non-manifold representation is sufficient and efficient for describing adjacency ordering and is also suitable for operations managing connectivities. Since geometric information is generalized by abstracting geometric data type, the interface is so flexible to adapt itself to specific geometric data. Furthermore, the interface enables us to handle simultaneously various types of geometric data by using multiple descriptions.

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This paper describes a method which uses a tape-guide technology simulated with FEM for stabilizing the running of ultra thin tape needed for high density recordings. The running errors of the ultra thin tape are caused by the rotating resistance of the drum. In order to solve this problem a new tape-guide technology has been developed which forces the tape to go along the lead of the drum by establishing an acute angle between the lead of the drum and the direction that the tape is going as it goes along the drum. The results from the simulation show that if the value of the angle is more than 0.03° it is possible to restrain the errors to less than 0. 5μm. An experiment, using real materials and conducted to test the result of the simulation-analysis, shows a number of less than 5μm of trackstraightness errors and the tape-running is very stable. This method enables the usage of thinner tape. The thinness of the tape contributes to the VTR's long-recording capability and compactness.

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A method is proposed to convert the energy density distribution of the laser beam to an adequate one for laser processing by applying a kaleidoscope of taper pipe taking a case of CO₂ laser as an example. The energy density distributions of singlemode and multi-mode laser beams obtained by a kaleidoscope of taper pipe were calculated for cases in which the interferences of the beams were disregarded and also the interferences were taken into consideration. It is confirmed that the energy of the laser beam can be concentrated to its center in narrow ranges with use of the kaleidoscope of taper pipe. The optimum geometries of the kaleidoscope are also obtained through the calculations to concentrate the energy density distribution. In order to confirm the effect of the kaleidoscope, experiments were carried out to measure the energy density distribution of single-mode laser beam with use of the knife edge method, and the acrylic burn patterns were made with the single-mode laser beams concentrated by different methods. The experimental results were in good agreement with the calculations.

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This report describes the evaluation of CVD diamond powder produced from roll milling diamond films synthesized by the arc discharge plasma jet CVD as the grinding wheel. The metal bonded and the resinoid bonded grinding wheels are prepared using the CVD diamond powder. In case of the grinding of ZrO₂ with metal bonded wheel, the new cutting edge emerges moderately, and the grinding power is constant, however, in case of the grinding of Si₃N₄ with metal bonded wheel, the powder wear a lot, and the grinding power increases and decreases suddenly. In the grinding of Si₃N₄ with the resinoid bonded wheel, the powder pull out moderately, and the stable grinding power is given. The fracture in limited amounts occurs from the powder boundaries and the defects in crystal, and the fracture rate of CVD diamond is larger than that of the irregular diamond. The CVD diamond powder have remarkable characteristic that new cutting edges are easily produced in its grinding process. The CVD diamond powder can be expected for the candidate for ceramic materials processing.

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Micro machineries such as micro sensor & switch are produced by utilizing an anisotropic etching process, however, its chemical mechanism or etching process is not yet clarified. The present paper has analyzed the process for a variety of substrate (wafer) orientation & mask patterns and predicted the finished profile by the help of reactive cage effect. The new theory has been confirmed quantitatively comparing the analysis with the experimental etching rates.

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In this paper, smoothing of CVD diamond films by ion beam irradiation has been described. Diamond films are synthesized by arc discharge plasma jet CVD and microwave plasma CVD. Argon and oxygen gases are used as an ionized gas. As a result, by setting up an incident angle at 0° and 80°, smooth surfaces of diamond films have been obtained. When an ion beam is irradiated to microwave plasma CVD diamond films at 80°, the surface roughness is reduced from 3μmRmax to 0. 5μmRmax. Moreover, the mechanism ofsmoothing process of diamond films has been considered and described as a simple model.

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In the 1st report, a turning test was carried out with hardened steel SUJ2 (HRC66) and ceramic tools. The early fracture has been investigated experimentally. As a result, the method of expression has been proposed for the occurrence condition of the early fracture. This method consists of the maximum undeformed chip thickness and the critical cutting speed, and the relation of them can be described as a exponential equation. In this paper the usefulness of this method is clarified for work hardness (HRC42-62) and chamfer angle (O-55°). The main findings are as follows ; (1) The early fracture occurs in cutting speed over a certain speed in both cutting of lower hard steel and with chamfered cutting edges. (2) The critical cutting speed is changed by the work hardness and the chamfer angle. (3) In these cases, the occurrence conditions of early fracture can be described by the method of this paper. (4) Therefore, the early fracture equation proposed in this paper is practically useful.

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In this paper, a relation between the ground surface roughness and grinding phenomena of various fine ceramics is investigated by a systematical experiment. Results obtained are as follows : The state of ground surface corresponds to the surface generation phenomena per cutting edge.There is a near connection between the grinding force and the surface generation phenomenon, namely in grinding of fine ceramics, the brittle work materials produce low grinding forces and the grinding forces of ductile materials are relatively high. A grinding wheel, which is made of fine abrasive grains, make the work surface good in roughness;however, in this case, the effect of spark-out grinding on improvement of surface roughness decreases comparing with using rough grain wheel.

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This paper proposes a new convex spherical finishing method for end of small diameter glass rods, and also describes the kinematical basic theory and the newly designed polishing machine for obtaining spherical surface on them. The distinctive feature of this method is to use the lip type finishing tool whose form is hollow and a cone shape. The inner cone surface is used for tool surface. The spherical surface on end of glass rods is able to be formed by pushing the end of them perpendicu-larly against the inner cone surface of the tool, rotating the glass rods at low speed and the tool at high speed. The experiments are performed for optical small diameter glass rod works (φ2.0×L110 mm), using lip type grinding tool filled up with 7 μm diamonds uniformly to the inner cone surface and lip type polishing tool coated with soft pitch under supplying CeO₂ powders slurry. Following conclusions are obtained : (1) Spherical radius R of the work can be changed continuously with adjustment of the work position against the tool. (2) Surface roughness and form accuracy values of spherical surface reach approximately 2 nm Rmax and 0.1 μm P-V, and R is 2.5 mm in agreement with the calculated value on the experiments.

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FIAC-System (Fuzzy Intelligent & Automatic Control System) is developed in order to achieve the intelligent automation of grinding process. In this paper, fuzzy in-process control grinding techniques are adapted to wheel head infeed control, in which grinding phenomena are sensed and best grinding conditions are choiced by predictive fuzzy theory in real time. Main conclusions are as follows : (1) In FIAC grinding, the ideal infeed control grinding process, in which the bigger infeed rate should be given in early stage for high efficiency and gradually decreasing infeed rate to spark-out point should be given for high quality, can be established. (2) By means of estimating the size error on account of workpiece thermal contraction occurred after spark-out, final size error and the deflection become extremely smaller. (3) In size accuracy and surface roughness, FIAC grinding is superior to two plunge speed grinding which has same efficiency as FIAC one.

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This paper describes the development of a piezoelectric micropress and its application to the blanking of thin sheet metals. As is generally known, the piezoelectric actuator is excellent for precise positioning, so device development of a precise micropress using a piezoelectric actuator for light processing is feasible. However, as the elongation of the actuator itself is limited to several micro-meters, an additional mechanism is necessary to gain longer displacement sufficient for press work. In this investigation, a structure known as a “two-stage differential action amplitude magnifying mechanism” is used to gain a displacement sufficient to press-work the sheet metals. The design conditions for the mechanism available for the press are considered, and the detailed dimensions are determined by FFM analysis. The micropress simply consists of the mechanism mentioned above, actuators, driver, and blanking die. The characteristics of the press developed are investigated, and results show that the specifications are slightly different from design values, but the press capacity of 130N generated force and 300μm stroke is quite sufficient to perform the blanking tests planned previously. Actual burr-free blanking tests requiring accurate positioning of the punch are performed, and perfectly burr-free blanked products are obtained by means of the micropress developed.

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To analyze the relational motions between the human body and body parts under such posture controls as jumping, somersault and landing, the describing functions were improved in this paper for the translational and rotational motions of a hard-soft link system which has such engineering models as viscoelastic resiliences and concentrated masses. Secondly, the equations of floating revolutions of the whole body were discussed based on the moments of momenta of rigid bodies under gravity.

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An optical axis determination method for semiconductor laser systems of invisible wave length, e. g. 1.3, 1.5 μm, has been proposed. A semiconductor laser module with a microlens shaped by the surface tension of melted glass is discussed. The optical axis of the system is determined as follows. At first, the axis of the lens is searched from interference fringes made by reflecting He-Ne laser visible light. This axis is then used as the reference axis. Next, the electromotive current in the semiconductor laser is measured by illuminating the semiconductor laser with a He-Ne laser light from the opposite direction against the laser emission. At the same time, the angle of the illuminating laser light is continuously changed by means of an f·θ lens. The illuminating laser light axis which corresponds to the desired optical axis is found when the maximum electromotive current is obtained. The spacial orientated axis is determined by independently measuring the maximum currents along two directions orthogonal to each other.

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This paper describes photothermoelastic effect occurring at the IC lead's soldered joints. Irradiation of chopped LASER light on a lead frame produces flexural vibration caused by the thermoelastic bending. Conditions of soldered joints were modelled into 3 categories, that is “nomalsoldering”, “lifted leg”, “touching”. Flexural resonance was found in “lifted leg”. And the deflection of a lead frame varied according to the mechanical conditions of soldered joints, when irradiation spot position moved along the surface of a lead frame. Precise analysis of amplitude and phase of the vibration gave information on the conditions of soldered joints. In order to explain the experimental results, a calculation model was made. The thermoelastic bending was calculated under the assumption that the temperature difference existed along the thickness of the shell element. Difference between the phenomena occurring from the PT effect and the conventional photoacoustic effect were also observed through the detection of acoustic wave and optical deflection method.

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