公开(公告)号：US20190293735A1

公开(公告)日：2019-09-26

申请号：US16302264

申请日：2017-05-22

Applicant: TDK CORPORATION

Inventor： Kentaro USHIODA ,  Makoto KAMENO ,  Chengbin LIN ,  Shuichi OKAWA

IPC: G01R33/09 ,  H01L43/08

Abstract: An object of the present invention is to enhance detection accuracy of a magnetic sensor having four bridge-connected magnetic sensing elements. A magnetic sensor includes magnetic layers 41-43 provided on a surface of the sensor substrate 20 and bridge-connected magnetic sensing elements R1-R4. The magnetic layer 41 includes a main area M1 and a converging area S1 having a width gradually reduced with increasing distance from the main area M1, the magnetic layer 42 includes a main area M2 and converging areas S5, S7 each having a width gradually reduced with increasing distance from the main area M2, and the magnetic layer 43 includes a main area M3 and converging areas S6, S8 each having a width gradually reduced with increasing distance from the main area M3. The end portions of the converging areas S1-S4 and the end portions of the converging areas S5-S8 face each other, respectively, through gaps G1-G4, respectively. The magnetic sensing elements R1-R4 are disposed on magnetic paths formed by the gaps G1-G4, respectively. According to the present invention, detection accuracy is enhanced because a magnetic flux generated by current flowing in one magnetic sensing element does not affect the other sensing element.

公开(公告)号：US20240248156A1

公开(公告)日：2024-07-25

申请号：US18566578

申请日：2022-05-31

Applicant: TDK Corporation ,  National University Corporation YOKOHAMA National University

Inventor： Tamon KASAJIMA ,  Shuichi OKAWA ,  Masanori KOSUDA ,  Yasushi TAKEMURA ,  Bagus Trisnanto Suko

IPC: G01R33/06 ,  G01R33/12

CPC classification number: G01R33/06 ,  G01R33/1276

Abstract: A magnetic field measurement device includes: an excitation coil that applies an excitation AC magnetic field to an object to be measured including a magnetic material to make a magnetization change of the magnetic material exhibit linear response; a detection coil that detects a primary detection magnetic field caused due to the magnetization change of the magnetic material to generate a primary detection signal; a magnetic field generation coil that generates a secondary detection magnetic field based on the primary detection signal; and a magnetic sensor that detects the secondary detection magnetic field to generate a secondary detection signal including a non-sine wave component. With this configuration, it is possible to obtain the secondary detection signal including a non-sine wave component without making the magnetization change of the magnetic material exhibit nonlinear response, allowing reduction in the current value and frequency of a current flowing in the excitation coil.

公开(公告)号：US20240094262A1

公开(公告)日：2024-03-21

申请号：US18264304

申请日：2022-01-28

Applicant: TDK Corporation

Inventor： Shuichi OKAWA

IPC: G01R15/18 ,  G01R19/00

CPC classification number: G01R15/18 ,  G01R19/0092

Abstract: A magnetic sensor includes: a sensor chip having magnetic layers magnetically coupled to each other through a magnetic gap and a magnetic sensing element disposed on a magnetic path formed by the magnetic gap; an external magnetic member magnetically coupled to one of the magnetic layer 21; and a measuring current coil wound around the external magnetic member and through which a current for generating a magnetic field to be measured flows. The magnetic sensing element 31 and the magnetic layers are thus integrated in the sensor chip, so that the magnetic gap can be designed to be very small in width, and a leakage magnetic field can be applied in large amounts to the magnetic sensing element. Thus, even when the current I flowing in the measuring current coil is weak, a magnetic field generated by the current I can be detected with high sensitivity.

公开(公告)号：US20170238834A1

公开(公告)日：2017-08-24

申请号：US15501777

申请日：2015-08-05

Applicant: National University Corporation Tokyo Medical and Dental University ,  TDK CORPORATION

Inventor： Shigenori KAWABATA ,  Satoshi SUMIYA ,  Shuichi OKAWA

IPC: A61B5/05

CPC classification number: A61B5/05 ,  A61B5/04005 ,  A61B5/04007 ,  A61B5/04009 ,  A61B5/0515 ,  A61B5/062 ,  A61B5/4064 ,  A61B5/407 ,  A61B5/6852 ,  A61B5/6853 ,  A61B5/6868 ,  A61B5/687 ,  A61B5/6873 ,  A61B5/6876 ,  A61B5/6885 ,  A61B2562/043

Abstract: A biomagnetism measurement device includes a tubular body, an inflatable portion inflatable upon supply of gas, and a magnetic sensor portion that detects a magnetic field from outside the tubular body. The inflatable portion is located at a required region of the tubular body, and the magnetic sensor portion is fixed to an inner wall of the inflatable portion. The tubular body and the inflatable portion include the same material, and the wall thickness of the inflatable portion is thinner than that of the tubular body.