公开(公告)号：US11346660B2

公开(公告)日：2022-05-31

申请号：US17014308

申请日：2020-09-08

Applicant: MITUTOYO CORPORATION

Inventor： Masato Kon ,  Hiromu Maie ,  Seiji Sasaki ,  Jyota Miyakura

IPC: G01B15/04

Abstract: A calibration method of an X-ray measuring device includes: a front-stage feature position calculation step of parallelly moving spheres disposed in N places a plurality of times, and identifying centroid positions ImPos(1 to Q)_Dis(1 to M)_Sphr_(1 to N) of projected images of the spheres in the N places; an individual matrix calculation step of calculating an individual projection matrix PPj (j=1 to Q) for each of the spheres; an individual position calculation step of calculating moving positions Xb of the spheres on the basis of the individual projection matrix PPj (j=1 to Q); a coordinate integration step of calculating specific relative position intervals X(1 to N) of the spheres; a rear-stage feature position calculation step; a transformation matrix calculation step of calculating a projective transformation matrix Hk (k=1 to Q); a rotation detection step; a position calculation step; and a center position calculation step.

公开(公告)号：US11004243B2

公开(公告)日：2021-05-11

申请号：US16455912

申请日：2019-06-28

Applicant: THE UNIVERSITY OF TOKYO ,  MITUTOYO CORPORATION

Inventor： Yutaka Ohtake ,  Tomonori Goto ,  Masato Kon

IPC: G06T11/00 ,  G06T3/40

Abstract: Projection images of reduced resolution are generated by reducing resolution of filtered projection images and/or reducing the number of filtered projection images. Volume data of reduced resolution is generated by performing CT reconstruction using the projection images of reduced resolution. Each voxel of the volume data of reduced resolution is provisionally divided. The provisionally divided voxels are compared in voxel value before and after provisional division. If a difference in voxel value before and after the provisional division is greater than a threshold, the provisional division is determined to be valid, and division is further continued. If the difference in voxel value before and after the provisional division is less than or equal to the threshold, the provisional division is determined to be invalid and the voxel ends being divided.

公开(公告)号：US10753887B2

公开(公告)日：2020-08-25

申请号：US16250167

申请日：2019-01-17

Applicant: MITUTOYO CORPORATION

Inventor： Kozo Ariga ,  Gyokubu Cho ,  Hidemitsu Asano ,  Masato Kon

IPC: G01N23/046

Abstract: An X-ray CT measuring apparatus configured to emit an X-ray from an X-ray source while rotating a subject arranged on a rotary table, and obtain a tomographic image of the subject by reconstructing projection images, includes an imaging unit for imaging the subject on the rotary table from above or sideways, an obtaining unit for obtaining an image of the subject while rotating the subject, a calculating unit for calculating a maximum outer diameter of the subject during rotation by using the obtained image of the subject, and a setting unit for setting a movement limit of the rotary table on the basis of the maximum outer diameter.

公开(公告)号：US11561091B2

公开(公告)日：2023-01-24

申请号：US16455883

申请日：2019-06-28

Applicant: THE UNIVERSITY OF TOKYO ,  MITUTOYO CORPORATION

Inventor： Yutaka Ohtake ,  Tasuku Ito ,  Tomonori Goto ,  Masato Kon

IPC: G01B15/02 ,  G01N23/046 ,  G01B15/04 ,  G01B15/00

Abstract: In measuring a dimension of an object to be measured W made of a single material, a plurality of transmission images of the object to be measured W are obtained by using an X-ray CT apparatus, and then respective projection images are generated. The projection images are registered with CAD data used in designing the object to be measured W. The dimension of the object to be measured W is calculated by using a relationship between the registered CAD data and projection images. In such a manner, high-precision dimension measurement is achieved by using several tens of projection images and design information without performing CT reconstruction.

公开(公告)号：US11234670B2

公开(公告)日：2022-02-01

申请号：US16291674

申请日：2019-03-04

Applicant: MITUTOYO CORPORATION

Inventor： Sadayuki Matsumiya ,  Hidemitsu Asano ,  Masato Kon

IPC: G06K9/00 ,  A61B6/00 ,  G01N23/046 ,  G06T11/00 ,  A61B6/03

Abstract: When generating a tomographic image using a measuring X-ray CT apparatus that is configured to emit X-rays while rotating a specimen that is arranged on a rotary table and reconstruct a projection image thereof to generate a tomographic image of the specimen, an amount of geometric error that is included in the projection image is obtained in advance and stored; the projection image is corrected using the stored amount of geometric error; and a tomographic image is reconstructed using the corrected projection image.

公开(公告)号：US11170572B2

公开(公告)日：2021-11-09

申请号：US16676943

申请日：2019-11-07

Applicant: THE UNIVERSITY OF TOKYO ,  MITUTOYO CORPORATION

Inventor： Yutaka Ohtake ,  Yukie Nagai ,  Tomonori Goto ,  Seiji Sasaki ,  Masato Kon

IPC: G06T17/20

Abstract: An isosurface mesh M is generated by extracting voxels having a certain CT value from volume data obtained by X-ray CT. A gradient vector g of a CT value is calculated at each vertex p of the isosurface mesh M. A plurality of sample points S are generated in positive and negative directions of the calculated gradient vector g. Gradient norms N of CT values at the respective generated sample points S are calculated. The vertex p of the isosurface mesh is moved and corrected to a sample point Sm having the maximum norm Nm calculated.

公开(公告)号：US11037337B2

公开(公告)日：2021-06-15

申请号：US16299513

申请日：2019-03-12

Applicant: MITUTOYO CORPORATION

Inventor： Kozo Ariga ,  Gyokubu Cho ,  Hidemitsu Asano ,  Masato Kon

IPC: A61B6/00 ,  G06T11/00 ,  G01N23/046

Abstract: When generating a measurement plan for measuring X-ray CT that performs X-ray irradiation while rotating a test object, and in doing so acquires projection image data, reconstructs volume data from the projection image data, and measures a targeted measurement location in the volume data, the present invention calculates required measurement accuracy and a measurement field of view range based on tolerance information included in CAD data of the test object and a measurement location on the test object defined by a measurement operator ahead of time, and automatically generates, from this information, an optimized measurement plan that minimizes the number of measurements.

公开(公告)号：US20190227004A1

公开(公告)日：2019-07-25

申请号：US16250167

申请日：2019-01-17

Applicant: Mitutoyo Corporation

Inventor： Kozo ARIGA ,  Gyokubu Cho ,  Hidemitsu Asano ,  Masato Kon

IPC: G01N23/046

Abstract: An X-ray CT measuring apparatus configured to emit an X-ray from an X-ray source while rotating a subject arranged on a rotary table, and obtain a tomographic image of the subject by reconstructing projection images, includes an imaging unit for imaging the subject on the rotary table from above or sideways, an obtaining unit for obtaining an image of the subject while rotating the subject, a calculating unit for calculating a maximum outer diameter of the subject during rotation by using the obtained image of the subject, and a setting unit for setting a movement limit of the rotary table on the basis of the maximum outer diameter.

公开(公告)号：US10190996B2

公开(公告)日：2019-01-29

申请号：US15093134

申请日：2016-04-07

Applicant: MITUTOYO CORPORATION

Inventor： Sadayuki Matsumiya ,  Hidemitsu Asano ,  Masato Kon

IPC: B65G47/244 ,  G01N23/046

Abstract: An XY shift mechanism can shift a rotary table in a two-dimensional direction (XY direction) orthogonal to a rotation axis of the rotary table. By collaborative control of the shift position of the rotary table in the two-dimensional direction in synchronization with the rotation of the rotary table, rotation is made possible about a virtual rotation center that is set at an arbitrary position on the rotary table. The collaborative control of the shift position of the rotary table in the two-dimensional direction also corrects rotation eccentricity owing to the eccentricity of the rotary table. Thus, the virtual rotation center can be set at an arbitrary position on the rotary table, thus enabling obtainment of high resolution tomographic images of a plurality of regions of interest of an object, without the need for repositioning of the object.

公开(公告)号：US11510643B2

公开(公告)日：2022-11-29

申请号：US17024061

申请日：2020-09-17

Applicant: MITUTOYO CORPORATION

Inventor： Hidemitsu Asano ,  Masato Kon

IPC: A61B6/00 ,  A61B6/03 ,  A61B6/04

Abstract: Volume data is generated by performing a CT scan with a spherical calibration jig having known dimensions in contact with an object. A profile of the surface shape of the object in the volume data is obtained, and a boundary surface of the spherical calibration jig is calculated from the center coordinates of the spherical calibration jig. A correction value for adjusting a boundary surface of the object determined from the gradient of the profile to the boundary surface of the spherical calibration jig is determined, and the boundary surface of the object is corrected by using the correction value. The shape of the object is determined by using the corrected boundary surface. The precision of measurement X-ray CT can thus be increased by accurately detecting the boundary surface of the object.