位相共役波の発生法について解説した.理想を言えば,位相共役鏡が,レンズや鏡や偏光素子などの光学部品と同列に並び,特殊な鏡の一種として手軽に使われるようになることが望ましい.そのためには,弱い光にもすばやく応答し,忠実度の高い反射波が高反射率で,安定して,波長の広い範囲で得られるというのが理想である.
大出力レーザにはSBS法が使われ,よい結果が得られている.光情報処理や光計測ではフォトリフラクティブ材料を使った4光波混合法が使われるが,応答速度と安定度において大幅の改善が望まれる.

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天文学用の補償光学は,実用段階に入りつつあり,すでにサイエンスデータが出始めている.特に赤外域では必須の装置と考えられるようになってきた.今後は,レーザガイド星を使った可視光用(多素子)補償光学の開発へと進んでいくであろう.そのためには,マルチプルレーザガイド星による波面の立体的測定等,解決すべき課題が多い.8mクラスの望遠鏡に組み込まれた補償光学系によって期待される天文学の成果は,数多くあるが,例えば太陽系外の惑星の探査がある.太陽系外にも地球や木星のような惑星があることは信じられてはいるが,まだ見つけられていない.その原理は,そのような惑星が星の非常に近傍にあり,かつ星と比べてはるかに暗いからである.補償光学と「コロナグラフ」という中心星の散乱光をおさえる装置を組み合わせれば,見つけることが可能になる.ほかに中心にブラックホールがあると考えられている活動銀河中心核の構造の解明に大きな役割を果たすであろう.また,宇宙の年齢を決めるためには遠方の銀河までの距離を知らねばならないが,補償光学を用いて,おとめ座銀河団内の銀河にあるセファイド(本当の明るさと変光周期との間に一定の関係がある)変光星が星として分解できるようになり,これによってこの銀河団までの距離が精密にわかるようになる.
天文学に近い応用では,深宇宙光通信に用いる軌道上の大型軽量望遠鏡面精度をあげることに使われるであろう.また,軍用でない,人工衛星の監視にも使うことができる.工業的には,ウラン235同位元素の分離に,補償光学の応用の研究がされている,など徐々に広がりつつある.

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A model is proposed for the total tuning of feed drive systems in NC machine tools. The model should be sufficiently simple for calculation, yet precise for analysis of servo system stability. Parameters of the model are identified by curve fitting of the frequency response measured by the DAC measuring method. This model was tested by measuring the responses of feed drive systems in a existing machining center. As a result, model was sufficiently correct for practical use.

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This paper describes the development of an insertion technique of parts with small radial clearance. The insertion principle is based on measurements of electrostatic capacitance change between the conducting surface of the parts to be paired. If, for example, a bar part and a fixed hole part are set parallel to each other with small vertical clearance, they form a capacitor whose dielectric medium is air. The capacitance depends on the overlapping surface area of the paired parts if the vertical clearance is constant. During insertion, if the bar part can move freely with respect to the horizontal plane of the fixed hole part, the capacitance is minimum when the horizontal centerlines of both parts coincide. Under this condition, the bar part can be inserted smoothly into the hole part. The practicality of the method is investigated through the experiments. As the result, it was found that the capacitance measurement method is an effective means of ensuring the proper positioning of parts during insertion. In the case of insertion of cylindrical parts and rectangular block parts, positioning error is within 4 μm.

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The present paper describes damping effects of impact damper having a spring supported impactor without gap and pre-pressure. The transient response of the damper is investigated for various conditions based on experiments and numerical simulations. The results obtained are as follows :1) The newly designed damper without gap and pre-pressure practically has no residual vibration and the damping effects are not dependent on amplitude. 2) The damper has optimum damping effect when natural frequency ratio is selected around 0.5.

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A original method to get long depth of focus of optical microscope image using computer image processing has been proposed. At first the principle of proposed method is explained, then the validity of the method is shown experimentally. The microscope objective is determined positioning by actuator such as PZT. At each located position digital picture image through CCD camera is taken into a computer. The computer extracts the area where the image is in focus from these pictures, then it composes whole frame image. The depth of focus of the composite picture image is nearly equal to the distance of motion of objective lens. As for the methods that distinguish between in-focus-area and out-of-focus-area, four different methods have been proposed. Processing time and accuracy point of view Hadamard transfer method is the best within these four methods. This method has been applied to the observation of several specimens such as standard surface roughness test piece, grooved metal surface and so on, with excellent results. By adding displacement information to the recorded CCD camera image, this method is also applicable to the three dimensional surface topography measurement.

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A laser power density distribution is one of the important factors that defines the solidified unit shape in the rapid prototyping. In this paper, several methods are proposed to determine a laser power distribution, i. e., a method using two interference filters or using one interference filter with numerical calculus, and using least square method. It is shown experimentally by identifying parameters of UV-Ar laser beam that the power density distribution in the three dimensional space around beam waist is described by the superposition of two Gaussian beams, and that estimated value is in good accordance with the measured results of power density distribution.

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The probe of this scanning near-field optical microscope (SNOM) is a dielectric sphere of 500 nm in diameter on a transparent substrate. The probe sphere is illuminated by evanescent wave which is formed by the incidence of He-Ne laser with the wave length of 632.8 nm from the inside of the substrate on the condition of total reflection. The light from the probe is collected by a conventional microscope through the substrate. The detected light intensity changes remarkably when a sample is brought in a near-field around the probe. The variation of detected light intensity in the near-field depends on refractive index of sample; the smaller real part of refractive index of sample, the more remarkable increase of detected light intensity. This result is explained by using an electric dipole model for the electromagnetic interaction between probe and sample. The vertical resolution of about 1 nm and lateral resolution of less than 20 nm are obtained for the developed microscope by measuring a standard specimen which is prepared by vacuum evaporation of metal.

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High-temperature superconductor YBa₂Cu₃O_7-x with strong pinning force has allowed the realization of stable magnetic suspension with no control. Superconducting magnetic bearing (SMB) using YBCO and permanent magnet, and SMB operation system were assembled. TWO SMB cooled down in a field cooling state by liquid nitrogen were proved to support a rotor weighing 2.5 kg up to 42 000 rpm. A radial run out of the rotor was 8 μm or less. The value can be considered for practical applications. The rotating performance at high speed has been disclosed by an active control assist in radial direction during accelerations.

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An 8 × 8 matrix relay, having a volume about one tenth that of conventional relays, has been developed using microsystem design and conventional machining technology. Also the performance of switch actuators is investigated to clarify the limits of miniaturization. The developed relay has 64 electromagnetic bi-stable switches and its dimensions are 28 mm × 32 mm×7 mm. The relay has a multilayered planer structure, which is popular in microelectromechanical system design. Its contact force is 10 mN, which is one tenth that of conventional relay. Also, mechanical and magnetic interferences between switch actuators and electrostatic interference among signal lines are analyzed theoretically. The results show that (a) the mechanical and electrical interferences are independent of length, (b) electrostatic interference is proportional to length, and (c) the limit of miniaturization is about one tenth of the prototype.

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First-principles molecular-dynamics simulations of H-terminated Si(001) surface interacting with H₂O molecule are carried out on the basis of density-functional theory, norm-conserving pseudopotential and plane-wave basis set. Stable atomic structure, charge density, atomic population, bond population and local energy are calculated about H-terminated Si(001) surface without H₂O, with H₂O, without surface step and with one atomic layer surface step. The following results are obtained: H-terminated Si(001) surface atom is stable, but as for the step edge atom interacting with H₂O, the backbond is weakened and the local energy rises higher than that of Si bulk atom. It suggests the possibility of removal chemical process of the step edge atom with the interaction of H₂O molecule.

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A machining process/tool wear monitoring system based on real-time sound recognition and neural network algorithm was developed. The system is composed of a high-speed digital filter bank unit, preliminary test/learning module, database module, and real-time monitoring module. The filter bank is constructed using DSP's and calculates sound patterns through digital filtering program in real-tine. Abnormality in overall process is monitored by comparing a current sound pattern with the standard pattern, which is calculated and registered in the database for each NC block through test machining prior to production machining. Since the overall change of the sound pattern due to tool wear is too small to be detected by simple comparison of pattern, the way to monitor tool wear more reliably by using the rate of change of pattern components and neural network algorithm is proposed. Evaluation tests were performed for the NC lathe operation in the real shop floor. Environmental noise was reduced remarkably by closing the protection door of machine. Monitoring results showed usefulness of the developed system. Especially tool wear monitoring could judge the time of tool change as exactly as an expert did.

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砥石作業面上の切れ刃の摩耗面の大きさとその配置を,湿式研削中にインプロセスで測定するための装置を製作し,その出力を検討した.その結果,以下のことがわかった.
(1)切れ刃の逃げ面摩耗面の位置と装置の出力波形のピークの位置とは一致する.
(2)測定の外乱の1つとなる砥石の回転むらの影響を排除するための具体的な方法を示した.
(3)測定は湿式研削中でも通常研削周速(30m/s)で可能であり,またドレッシング時の切れ刃の状態の監視にも適用できる.
(4)切れ刃の逃げ面摩耗の程度は,装置の出力ピークの面積で表すことができる.

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This paper deals with the growth of indentation cracks in glass which are dynamically observed by a newly developed crack observation system. The three dimensional structure of indentation cracks are also obtained from the measurement of a crack shape on a perpendicular section to the indentation surface. The main results obtained are as follows; (1) The three dimensional structure of indentation cracks is shown in Fig.4 in the main text. All of these cracks grow during the unloading process of an indentation. (2) Cracks rapidly grow within 0.01s after the onset of unloading then gradually decrease the growing rate. (3) The cracks are thought to be mechanically stable. (4) As the unloading rate decreases, the cracks grow more slowly.

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The author proposed a new system, called the workpiece-referred form accuracycontrol system (WORFAC), and confirmed an effectiveness of this manufacturingmethod. In the 3rd report, this method was applied to cylindrical turning usingan ordinary NC machine tool, and the corrective servo coefficient was found out.In this study, the effects of coefficient m for error convergency of the firstreferred surface and for disturbance elimination are cleared by both simulationon a computer and experiment of cylindrical turning. As to error convergency, using m, the error of first referred surface can be converged to zero. When mincreases to 1, the convergent time becomes longer. For the disturbance, due tom, the degree of elimination can be changed. At the start point of control, atransitional error of peak amount (1-m)A_d causes, and after converging, the (1-m)/(1+m)A_d error is remained, where A_d is the amplitude of disturbance.

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The study deals with 5-axis control tool path generation for side-milling cutters in the light of making use of 5-axis control machining centers having the potential of machining with high efficiency and accuracy. Concerning 5-axis control machining, there are two ways of using cutting edges; one is to use the top part such as ball-end mill and the other the side part described in the study. Most of 5-axis control machining is probably carried out by the former, however, there are some cases where the latter exerts the validity. In the study, the system developed enables the collision-free tool path generation for side-milling cutters which is transformed to actual 5-axis control NC data, taking account of the structure of 5-axis control machining centers. The validity of the system is experimentally confirmed.

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A method is proposed for planning an optimal machining sequence on automatic NC programming for turning. The method can determine a machining sequence which needs the least cutting time. In a process to determine the sequence, suitability of cutting conditions as well as interference between a tool and a workpiece is checked. A planning problem is represented as a graph based on the concept of "cycle". In the graph, an optimal transition is found among sets consisting of machining processes. And an algorithm is proposed to solve the problem applying the dynamic programming of optimality. Numerical evaluation of the algorithm shows that it needs less calculating cost than exhaustive search and Dijkstra's algorithm to determine an optimal machining sequence. Machining sequences determined by the algorithm are compared with those determined by a skilled worker. As a result, machining sequences determined by the algorithm always had less or equal cutting time than those determined by a skilled worker.

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In the strategy phase of the manufacturing system, the problems lie in the lack of the fundamental technologies with respect to the utilization of human's deep knowledge and skills. In this paper, therefore, proposed is the modeling method for the thought processes of the mature engineer, which are, in the other words, the engineers' schema and can be represented by the directed graph, where the node signifies the element of the problem. Assuming different cultural values of manufacturing as to be appeared in the thinking processes of experienced engineers, a new concept design method of machining cell is proposed so as to be suitable for the cultures of manufacturing that the engineers belong. And it is'clear that the proposed method is useful to build an anthoropocentric system with different cultural values for manufacturing, and that the modeling method becomes the fundamental technology in a region of human resource utilization.

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Non-manifold models have been studied in order to represent and manipulate the shape of products in design and manufacturing processes consistently. Most developments of non-manifold modeling are based on the Radial-edge structure which has complicated structures and operations of topologies. In this paper, a new non-manifold modeling method based on cells, which is named Cell-model, is proposed. A Cell-model is composed of two prime concepts; Cells as topological elements and Cell-lists as adjacencies of Cells. Orders among adjacent Cells, which are essential for topological information, can he derived from a Cell-model by applying Switching functions to Cell-lists and chaining the selected Cells. A set of basic operators for handling topological structures of Cell-models are defined, and the basic concept of set operations in the Cell-modeling is explained with an example of modeling processes.

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This paper describes a method for eliminating thermal deformation on an aluminum laminated plate fixed to a flexible printed circuit (FPC) by adhesive. The objective of this study is to develop a head-arm for a magnetic disk storage system. Thermal deformation is calculated using the finite element method and the composite beam method. The deformation caused by temperature changes can be eliminated by making the equivalent thermal expansion coefficient of the FPC and that of the aluminum equal. Two methods for achieving this are investigated: controlling the volume of copper leaf in the FPC and controlling the volume of stainless steel inserted in the adhesive layer. The following results are found. The width ratio of copper leaf needed to eliminate thermal deformation is 0.50-0.55, and the necessary thickness of stainless steel is 10-15 μm. These results indicate that the insertion of stainless steel in the adhesive layer is the more appropriate method for application in the development of a new head-arm.

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