When a work W rotates counterclockwise about an axis O.sub.w and is subjected to infeed grinding by a regulating wheel (1) which rotates clockwise about an axis O.sub.1 and a grinding wheel (2) which rotates clockwise about an axis O.sub.2, a load F acting on a blade (4), a load acting on the work W supported by the blade (4), and a load operating position y in the blade (4) at any given time are measured by a controller (20) based on the outputs of a first stress sensor S.sub.1 and a second stress sensor S.sub.2 and according to the correlation information stored in a storage device. If the component of a specified frequency extracted by performing frequency analysis of the time series of the load exceeds a threshold value, then designation processing is carried out to reduce the component of the designated frequency to the threshold value or less.

After a workpiece unit has been delivered from a cassette and before the workpiece unit is delivered to a chuck table, a value of the thickness of the workpiece unit is recognized on the basis of a result of a measurement performed by a measuring unit. The value of the thickness of the workpiece unit is represented by the sum of values of respective thicknesses of a workpiece and a tape affixed thereto. On the basis of the result of the measurement performed by the measuring unit, it is possible to decide whether or not the tape affixed to the workpiece has a desired thickness, i.e., whether the tape is of a desired type or not. As a result, a workpiece with an inadequate tape affixed thereto is prevented from being ground.

After a workpiece unit has been delivered from a cassette and before the workpiece unit is delivered to a chuck table, a value of the thickness of the workpiece unit is recognized on the basis of a result of a measurement performed by a measuring unit. The value of the thickness of the workpiece unit is represented by the sum of values of respective thicknesses of a workpiece and a tape affixed thereto. On the basis of the result of the measurement performed by the measuring unit, it is possible to decide whether or not the tape affixed to the workpiece has a desired thickness, i.e., whether the tape is of a desired type or not. As a result, a workpiece with an inadequate tape affixed thereto is prevented from being ground.

A substrate processing method of thinning a substrate having a protective tape attached on a front surface thereof includes measuring a thickness of the protective tape; and grinding, by using a grinder, a rear surface of the substrate held by a substrate holder.

A substrate processing method of thinning a substrate having a protective tape attached on a front surface thereof includes measuring a thickness of the protective tape; and grinding, by using a grinder, a rear surface of the substrate held by a substrate holder.

A grinding apparatus including a chuck table for holding a wafer, a grinding unit having a spindle for rotating a grinding wheel, an inclination adjusting unit for adjusting the inclination of the rotation axis of the chuck table with respect to the rotation axis of the spindle, a touch panel, and a control portion. The control portion is adapted to compare the information regarding the target sectional shape input into a target shape input field with the information regarding the present sectional shape input into a present shape input field and then control the inclination adjusting unit to change the inclination of the rotation axis of the chuck table so that the wafer is ground to obtain the target sectional shape of the wafer.

In a first step, an output of an eddy current sensor is measured while a polishing target whose film thickness has been known is in contact with the polishing face, thereby obtaining a measurement value of the eddy current sensor which corresponds to the film thickness. In a second step, an output of the eddy current sensor is measured when the polishing target is polished while pressed against the polishing face, thereby obtaining a measurement value of the eddy current sensor that corresponds to a film thickness during polishing. A correspondence relationship between the film thickness of the polishing target and the measurement value of the eddy current sensor is determined from the measurement value obtained in the first step and the measurement value obtained in the second step.

In a first step, an output of an eddy current sensor is measured while a polishing target whose film thickness has been known is in contact with the polishing face, thereby obtaining a measurement value of the eddy current sensor which corresponds to the film thickness. In a second step, an output of the eddy current sensor is measured when the polishing target is polished while pressed against the polishing face, thereby obtaining a measurement value of the eddy current sensor that corresponds to a film thickness during polishing. A correspondence relationship between the film thickness of the polishing target and the measurement value of the eddy current sensor is determined from the measurement value obtained in the first step and the measurement value obtained in the second step.

The present application discloses a method for calibrating a measuring probe in a gear cutting machine by using a workpiece received in a workpiece holder of the gear cutting machine, wherein the measuring probe includes a measuring probe tip which is movably arranged on a measuring probe base, wherein the deflection of the measuring probe tip relative the measuring probe base can be determined via at least one sensor of the measuring probe, and wherein the measuring probe is traversable relative to the workpiece holder via at least two axes of movement of the gear cutting machine. The method comprises rotating the workpiece via an axis of rotation of the workpiece holder and traversing the measuring probe via the at least two axes of movement of the gear cutting machine such that in the case of a perfect calibration the touch point of the measuring probe tip on the tooth flank would remain unchanged.

The present disclosure provides a fully automatic gemstone polishing robot. An aspect of the present disclosure provides an automatic gemstone polishing robot comprising: a gemstone polishing unit, comprising a gemstone holding unit for supporting a gemstone in contact with an abrasive surface, and configured to polish said gemstone in a plurality of iterations based on a feedback signal; an image capturing unit to capture, in one or more of the plurality of iterations, at least one image of the gemstone; and an image processing unit, which when executed by one or more processors, analyzes said at least one image of the gemstone with respect to one or a plurality of gemstone parameters, wherein the image processing unit is further configured to compare the one or a plurality of analyzed gemstone parameters with one or a plurality of pre-determined gemstone parameters to generate the feedback signal to be transmitted to the gemstone polishing unit. Another aspect of the present disclosure relates to a method of polishing a gemstone utilizing the automatic gemstone polishing robot.