Abstract: An externally toothed gear of a strain wave gearing is made to flex into a shape conforming to an ellipsoidal curve. The externally toothed gear meshes with an internally toothed gear at the major-diameter position of the ellipsoidal curve. These two meshing positions gradually change in the circumferential direction of the both gears along the tooth trace direction. The number of external teeth of the externally toothed gear participating in meshing with the internally toothed gear can be increased. A strain wave gearing which has a high rigidity and is capable of reducing vibrational noise, can be realized.

Abstract: An externally toothed gear of a strain wave gearing is made to flex into a shape conforming to an ellipsoidal curve. The externally toothed gear meshes with an internally toothed gear at the major-diameter position of the ellipsoidal curve. These two meshing positions gradually change in the circumferential direction of the both gears along the tooth trace direction. The number of external teeth of the externally toothed gear participating in meshing with the internally toothed gear can be increased. A strain wave gearing which has a high rigidity and is capable of reducing vibrational noise, can be realized.

Abstract: A gap measurement device 1 comprises a light source 5 for projecting light on a gap 3 to be measured, a lens optical system 6 for focusing on an imaging surface 7 a gap image 3A from light transmitted through the gap 3, and a light-receiving element 9 for receiving light of the gap image 3A formed on the imaging surface 7 of the lens optical system 6. A holed mask 8 provided with a light-transmitting hole 8a having a prescribed aperture size is arranged on the imaging surface 7, and the light-receiving element 9 receives the light of the gap image 3A via the hole 8a. A gap size at a point to be measured in an extended gap 3 can be measured by forming an image of the gap with the lens optical system 6 and placing the hole 8a of the holed mask 8 on the point to be measured on the imaging surface 7 of the lens optical system 6.

Abstract: In a self-calibration method of an angle detector, an angle interval between first and second scale reader heads are set, so that a single rotation is not equally divided into an integer number of portions by a value of the angle interval and that a plurality of rotations N are equally divided into M equal portions by the value of the angle interval. Readings by the scale reader heads during N rotations of the divided circle are obtained at a pre-set data sampling interval. From differences in readings by these scale reader heads, data of the sequential two-point method relating to an angle scale error of the divided circle are obtained at the data sampling interval. The scale error of the divided circle at the data sampling interval is calculated by synthesizing the data using the fact that an average of the data for the rotations N reaches approximately zero.

Abstract: A gap measurement device 1 comprises a light source 5 for projecting light on a gap 3 to be measured, a lens optical system 6 for focusing on an imaging surface 7 a gap image 3A from light transmitted through the gap 3, and a light-receiving element 9 for receiving light of the gap image 3A formed on the imaging surface 7 of the lens optical system 6. A holed mask 8 provided with a light-transmitting hole 8a having a prescribed aperture size is arranged on the imaging surface 7, and the light-receiving element 9 receives the light of the gap image 3A via the hole 8a. A gap size at a point to be measured in an extended gap 3 can be measured by forming an image of the gap with the lens optical system 6 and placing the hole 8a of the holed mask 8 on the point to be measured on the imaging surface 7 of the lens optical system 6.

Abstract: In a self-calibration method of an angle detector, an angle interval between first and second scale reader heads are set, so that a single rotation is not equally divided into an integer number of potions by a value of the angle interval and that a plurality of rotations N are equally divided into M equal portions by the value of the angle interval. Readings by the scale reader heads during N rotations of the divided circle are obtained at a pre-set data sampling interval. From differences in readings by these scale reader heads, data of the sequential two-point method relating to an angle scale error of the divided circle are obtained at the data sampling interval. The scale error of the divided circle at the data sampling interval is calculated by synthesizing the data using the fact that an average of the data for the rotations N reaches approximately zero.

Abstract: According to one aspect of the invention, there is provided a sensor device which is capable of detecting a state of a movable stage using an easily manufacturable reference grating and capable of improving the accuracy of detection. The sensor device comprises a reference grating which has a configuration that is varied periodically in a two-dimensional direction. A light source emits light to the reference grating. A spectral unit has a plurality of openings to convert the light emitted by the light source into a plurality of light beams through the plurality of openings. A detector unit has a photodetector to receive collectively reflected light beams reflected by the reference grating. The detector unit is provided to detect a state of a movable body relative to the reference grating based on a change of the reflected light beams received by the photodetector.

Abstract: This invention relates to a stage device which is moved with high accuracy in an X-Y direction and a rotating direction using a planar motor. The invention is aimed at reducing the size of the stage device and at performing accurately measurement of a position of the stage to the base. The stage device comprises a scale unit having a scale part on the entire plane of the base, and three two-dimensional angle sensors disposed on a bottom surface of a movable stage part. The scale unit and the two-dimensional angle sensors form a surface encode. A position of the movable stage part is measured by the surface encoder.

Abstract: A radiation tomographic imaging apparatus includes a scanning device for scanning a predefined region in a subject, a prescribing device for prescribing beforehand a position at which an image of said subject is to be produced at a higher priority in the scan region in said subject and a reconstructing device for sequentially reconstructing an image of said subject from projection data obtained by said scanning device, wherein once projection data at said prescribed higher-priority position has been obtained from said scanning device, said reconstructing device reconstructs an image at said higher-priority position at a higher priority.

Abstract: According to one aspect of the invention, there is provided a sensor device which is capable of detecting a state of a movable stage using an easily manufacturable reference grating and capable of improving the accuracy of detection. The sensor device comprises a reference grating which has a configuration that is varied periodically in a two-dimensional direction. A light source emits light to the reference grating. A spectral unit has a plurality of openings to convert the light emitted by the light source into a plurality of light beams through the plurality of openings. A detector unit has a photodetector to receive collectively reflected light beams reflected by the reference grating. The detector unit is provided to detect a state of a movable body relative to the reference grating based on a change of the reflected light beams received by the photodetector.

Abstract: This invention relates to a stage device which is moved with high accuracy in an X-Y direction and a rotating direction using a planar motor. The invention is aimed at reducing the size of the stage device and at performing accurately measurement of a position of the stage to the base. The stage device comprises a scale unit having a scale part on the entire plane of the base, and three two-dimensional angle sensors disposed on a bottom surface of a movable stage part. The scale unit and the two-dimensional angle sensors form a surface encode. A position of the movable stage part is measured by the surface encoder.

Abstract: A processing terminal 10 includes a writing implement (ball point pen) 30. The writing implement 30 is provided with a tilt change detecting mechanism for detecting a change in a tilt with respect to a writing implement main body of a lead and a vibration detecting mechanism for detecting the change in the vibration of the vibrated lead at the time of handwriting. The processing terminal 10 produces handwriting motion information based on both of the detected changes in the tilt of the lead and in the vibration. A handwriting identification organization 20 compares handwriting motion information with inherent information stored previously to identify handwriting. Thereby it can achieve high reliability in an authentication system with a simple structure.

Abstract: A radiation tomographic imaging apparatus includes a scanning device for scanning a predefined region in a subject, a prescribing device for prescribing beforehand a position at which an image of said subject is to be produced at a higher priority in the scan region in said subject, and a reconstructing device for sequentially reconstructing an image of said subject from projection data obtained by said scanning device, wherein once projection data at said prescribed higher-priority position has been obtained from said scanning device, said reconstructing device reconstructs an image at said higher-priority position at a higher priority.

Abstract: A processing terminal 10 includes a writing implement (ball point pen) 30. The writing implement 30 is provided with a tilt change detecting mechanism for detecting a change in a tilt with respect to a writing implement main body of a lead and a vibration detecting mechanism for detecting the change in the vibration of the vibrated lead at the time of handwriting. The processing terminal 10 produces handwriting motion information based on both of the detected changes in the tilt of the lead and in the vibration. A handwriting identification organization 20 compares handwriting motion information with inherent information stored previously to identify handwriting. Thereby it can achieve high reliability in an authentication system with a simple structure.

Abstract: Provided is an apparatus for accurately sensing the position of a moving object in two dimensions as well as a change in the attitude of the object when the object is moving. The apparatus includes a scale and at least one angle sensor. The scale is constituted by an angular grid, which is formed on the surface of a scale substrate inclusive of a planar surface and freely curved surface thereof, and which has an angle-related property that varies in two different directions (the x and y directions) in the form of a known function. The angle sensor is arranged so as to confront the angular grid surface of the scale. Either the scale or the angle sensor is mounted on a moving object and the position of the moving object in two-dimensional coordinates is sensed during relative movement between the scale and the angle sensor.

Abstract: The method of self-calibrating for a sensor without using an additional device by using data sampling, an approximate value of linear errors obtained by performing the numerical integration of approximate values of a linear-error derivative, correcting the approximate value of the input value at each sampling point, and repeating the processing for correcting the approximate value of the linear error by necessary times.

Abstract: A new method of angle measurement is based on the internal reflection effect at an air/glass boundary. The method uses a differential detection scheme to largely reduce the inherent non-linearity of the reflectance versus the angle of incidence in internal reflection. With non-linearity reduced, the displacement of the angle of incidence can be determined accurately by measuring the reflectance. The resolution and measurement range are determined by the initial angle of incidence, the polarization state of light, and the number of reflections. Compared with interferometers and autocollimators, this method has the advantage of a simple sensor design for applications ranging from very wide measurement range to extremely high resolution. Apparatus for accomplishing the method comprises a beamsplitter, a pair of critical angle prisms and a pair of photodiodes.