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A position sensing microprobe has been developed which satisfies harsh requirements to establish a nano-CMM (coordinate measuring machine) proposed for measuring microparts with a target accuracy of less than 50 nm within a 10 mm cubed working volume. This paper deals with dynamic properties and position sensing accuracy of the improved microprobe system for the nano-CMM using an optically trapped probe sphere of 8.0 ^m in diameter. The probe sphere is forced to vibrate with about a hundred nanometer amplitude and high frequency based on optical radiation pressure control. It is possible to measure its dynamic motions with a higher accuracy using the newly developed optical system with a position sensing detector (PSD). It is experimentally suggested that the improved microprobe system can achieve nano-position sensing in the lateral direction.

Organic nonlinear crystals that are very soft and brittle have been machined into optical surfaces by single-point diamond turning using special machining conditions. The crystallographic orientations of materials to be cut and rake angles of diamond tools strongly affect the cutting mode. The surface roughness depends upon the cutting direction, rake angle and nose radius of the diamond tool, feed rate and lubricant. The surface roughness is not a factor in the depth of cut or cutting speed. The machined surfaces of 23nm p-v in flatness and less than 1nm rms in surface roughness were obtained.

Super-smooth optical glass surfaces have been obtained by grinding using an ultraprecision surface grinder and a cup-type resinoid-bonded diamond wheel without any polishing. This paper deals with some mechanisms of surface roughness generation for brittle materials in ductile mode grinding. The shape of the contact area between a cup-type diamond wheel and sample in ultraprecision grinding has been measured with an optical profiler. The shape is affected by the grain size of the diamond powder, feed rate, and grinding time. Surface roughness can be estimated by a simple surface generation model where the inner edge angles of the wheel and feed rate determine the surface roughness in the ductile mode. The inner edge angles are affected by various grinding conditions.

By developing several alloys with the composition TbxDy1-x, (Fex, Mn1-y)n, a giant magnetostriction actuator was manufactured. The output power of them is several times and the displacement is several ten times as much as PZT without a magnifier. A temperature controller to keep a fluctuation of the cooling water within 10m°C was developed for the actuator. An ultra-precise machine tool was also developed. equipping the present actuator. The depth of cut can be set with the accuracy of several nanometers by the actuator and cut by a turning diamond tool. The hard and brittle materials such as glass and ceramics were finished in ductile mode, and the surface roughness was obtained within several nanometers.

Summary The paper deals with the life, the wear of single crystal diamond tools and their effects on the micro-roughness and the residual stress of the surface layers, under various machining conditions. Three kinds of diamond tools, having different nose radii, were used for mirror finishing of aluminum alloy workpieces. Cutting tests were carried out untill the cutting distance of a tool reached to 900Km. Despite of tool wear, the roughness of diamond-turned surface remains almost constant due to the burnishing effects. The micro-roughnesses are more or less varied by the feed rate and the nose radius of the cutting edge. Also the micro-roughness relate closely with the thrust forces. X-ray diffraction analysis was also conducted to determine the residual stress for each process. In the mirror finishing process, compressive stress of about 60 MPa remains on the surface layers. The thickness of the work-affected layer is merely on the order of submicrometers.