Magnetic sensor assembly

• US 20070080682A1
• Filed: 10/06/2005
• Published: 04/12/2007
• Est. Priority Date: 10/06/2005
• Status: Active Grant

• Current Assignee: Biosense Webster Incorporated (Johnson & Johnson)
• Original Assignee: Biosense Webster Incorporated (Johnson & Johnson)
• Inventors: Govari, Assaf, Altmann, Andres, Ephrath, Yaron
• Granted Patent: US 7,301,332 B2
• Time in Patent Office: Days
• US Class Current: 324/247
• CPC Class Codes: A61B 2090/3954 magnetic, e.g. NMR or MRI
• CPC Class Codes: A61B 2562/02 Details of sensors specially adapted for in-vivo measurements
• CPC Class Codes: A61B 2562/043 in a linear array
• CPC Class Codes: A61B 5/055 involving electronic [EMR] or nuclear [NMR] magnetic resonance, e.g. magnetic resonance imaging
• CPC Class Codes: A61B 5/06 Devices, other than using radiation, for detecting or locating foreign bodies for removing same A61B17/50 ; determining position of probes within or on the body of the patient
• CPC Class Codes: A61B 5/061 Determining position of a probe within the body employing means separate from the probe, e.g. sensing internal probe position employing impedance electrodes on the surface of the body A61B1/00158 takes precedence
• CPC Class Codes: A61B 5/062 using magnetic field
• CPC Class Codes: A61B 5/065 Determining position of the probe employing exclusively positioning means located on or in the probe, e.g. using position sensors arranged on the probe
• CPC Class Codes: A61B 90/39 Markers, e.g. radio-opaque or breast lesions markers
• CPC Class Codes: G01R 33/0206 Three-component magnetometers
• CPC Class Codes: G01R 33/09 Magnetoresistive devices

Abstract

A sensor assembly includes a first magneto-resistive field sensor in a first surface-mountable package, which measures first and second components of a magnetic field projected onto respective different first and second axes with respect to a spatial orientation of the sensor and to produce first position signals indicative of the measured first and second components. A second magneto-resistive field sensor in a second surface-mountable package measures at least a third component of the magnetic field projected onto at least a third axis with respect to the spatial orientation of the sensor, and to produce second position signals indicative of the measured third component. A substrate assembly orients the first field sensor in a first spatial orientation and to orient the second field sensor in a second spatial orientation so that the third axis is oriented out of a plane containing the first and second axes.

Claims

1. A sensor assembly, comprising:

a first magneto-resistive field sensor in a first surface-mountable package, which is arranged to measure first and second components of a magnetic field projected onto respective different first and second axes with respect to a spatial orientation of the first field sensor and to produce first position signals indicative of the measured first and second components;

a second magneto-resistive field sensor in a second surface-mountable package, which is arranged to measure at least a third component of the magnetic field projected onto at least a third axis with respect to the spatial orientation of the second field sensor, and to produce second position signals indicative of the measured third component; and

a substrate assembly having the first and second field sensors surface-mounted thereon, which is coupled to orient the first field sensor in a first spatial orientation and to orient the second field sensor in a second spatial orientation so that the third axis is oriented out of a plane containing the first and second axes.

2. The sensor assembly according to claim 1, wherein the substrate assembly comprises a flexible substrate material bent so as to orient the first and second field sensors.

3. The sensor assembly according to claim 2, wherein the flexible substrate material comprises one or more slots so as to enable bending the substrate assembly.

4. The sensor assembly according to claim 1, wherein the substrate assembly comprises two or more sections interlocked into one another so as to orient the first and second field sensors.

5. The sensor assembly according to claim 4, wherein the two or more sections comprise at least one slot so as to enable interlocking the sections into one another.

6. The sensor assembly according to claim 1, wherein the substrate assembly comprises a printed circuit board (PCB) material.

7. The sensor assembly according to claim 6, and comprising electrical conductors disposed on the PCB material so as to provide electrical interconnection for at least one of the first and second field sensors.

8. The sensor assembly according to claim 1, wherein the sensor assembly has a size smaller than 2 by 2 by 4 mm.

9. Position sensing apparatus, comprising:

one or more field generators, which are arranged to generate a magnetic field;

a sensor assembly, comprising;

a first magneto-resistive field sensor in a first surface-mountable package, which is arranged to measure first and second components of the magnetic field projected onto respective different first and second axes with respect to a spatial orientation of the first field sensor and to produce first position signals indicative of the measured first and second components;

a second magneto-resistive field sensor in a second surface-mountable package, which is arranged to measure at least a third component of the magnetic field projected onto at least a third axis with respect to the spatial orientation of the second field sensor, and to produce second position signals indicative of the measured third component; and

a substrate assembly having the first and second field sensors surface-mounted thereon, which is coupled to orient the first field sensor in a first spatial orientation and to orient the second field sensor in a second spatial orientation, so that the third axis is oriented out of a plane containing the first and second axes; and

a control module, which is arranged to receive the first and second position signals and to calculate a spatial position of the sensor assembly with respect to the one or more field generators responsively to the position signals.

10. The apparatus according to claim 9, wherein the magnetic field comprises a direct current (DC) magnetic field.

11. The apparatus according to claim 9, wherein the position sensor is adapted to be coupled to an object inserted into a body of a patient, and wherein the control module is arranged to determine position coordinates of the object inside the body.

12. The apparatus according to claim 9, wherein the substrate assembly comprises a flexible substrate material bent so as to orient the first and second field sensors.

13. The apparatus according to claim 9, wherein the substrate assembly comprises two or more sections interlocked into one another so as to orient the first and second field sensors.

14. The apparatus according to claim 9, wherein the substrate assembly comprises a printed circuit board (PCB) material.

15. A method for producing a sensor assembly, comprising:

providing a first magneto-resistive field sensor in a first surface-mountable package, which is arranged to measure first and second components of a magnetic field projected onto respective different first and second axes with respect to a spatial orientation of the first field sensor and to produce first position signals indicative of the measured first and second components;

providing a second magneto-resistive field sensor in a second surface-mountable package, which is arranged to measure at least a third component of the magnetic field projected onto at least a third axis with respect to the spatial orientation of the second field sensor, and to produce second position signals indicative of the measured third component;

surface-mounting the first and second field sensors on a substrate assembly so as to orient the first field sensor in a first spatial orientation and to orient the second field sensor in a second spatial orientation, so that the third axis is oriented out of a plane containing the first and second axes.

16. The method according to claim 15, wherein the substrate assembly comprises a flexible substrate material, and comprising bending the substrate assembly so as to orient the first and second field sensors.

17. The method according to claim 16, wherein the flexible substrate material comprises one or more slots so as to enable bending the substrate assembly.

18. The method according to claim 15, wherein the substrate assembly comprises two or more sections, and comprising interlocking the two or more sections into one another so as to orient the first and second field sensors.

19. The method according to claim 18, wherein the two or more sections comprise at least one slot so as to enable interlocking the sections into one another.

20. The method according to claim 15, wherein the substrate assembly comprises a printed circuit board (PCB) material.

21. The method according to claim 20, and comprising disposing electrical conductors on the PCB material so as to provide electrical interconnection for at least one of the first and second field sensors.

22. The method according to claim 15, wherein the sensor assembly has a size smaller than 2 by 2 by 4 mm.