US6147480A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Detection of metal disturbance
Assignee: Biosense Webster Inc
•
Filing: 1998-10-15
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Granted: 2000-11-14
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Expires: 2018-10-15
Abstract
Abstract A method for tracking an object using energy fields, in the presence of interference due to introduction of an article responsive to the fields, in the vicinity of the object. One or more desired energy fields are produced in the vicinity of the object, and a characteristic of energy fields induced due to introduction of the article is determined. Signals are generated responsive to the energy fields at a plurality of locations of the object after introduction of the article. Spatial coordinates of the object are determined, responsive to the generated signals and the determined characteristic.
Inventors
- 👤 Daniel Osadchy
- 👤 Assaf Govari
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 21:51
CPC Classifications
A; A61; A61B; A61B5/00; A61B5/06; A61B34/00; A61B34/20; A61B5/061; A61B5/062; A61B2034/2046; A61B2034/2051; A61B90/00; A61B90/08; A61B2090/0807; A61B2090/0808; A61B2090/0809
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
133 words
A method for tracking an object using an energy field, in the presence of interference due to introduction of an article responsive to the field, in the vicinity of the object, comprising: producing a first energy field in the vicinity of the object; identifying and determining a characteristic of a parasitic energy field induced responsive to the first field, due to introduction of the article; receiving signals responsive to the first energy field and the parasitic energy field generated at a plurality of locations of the object after introduction of the article; and determining spatial coordinates of the object responsive to the generated signals and the determined characteristic by determining a phase shift of the signals responsive to the parasitic energy field with respect to the signals responsive to the first energy field.
Claim 2
Independent Claim
133 words
A method for tracking an object using an energy field, in the presence of interference due to introduction of an article responsive to the field, in the vicinity of the object, comprising: producing a first energy field in the vicinity of the object; identifying and determining a characteristic of a parasitic energy field induced responsive to the first field, due to introduction of the article; receiving signals responsive to the first energy field and the parasitic energy field generated at a plurality of locations of the object after introduction of the article; and determining spatial coordinates of the object responsive to the generated signals and the determined characteristic by determining a phase shift of the signals responsive to the parasitic energy field with respect to the signals responsive to the first energy field.
Claim 3
Dependent Claim
46 words
A method in accordance with claim 1, wherein determining spatial coordinates comprises: determining an amplitude of the signals generated at a location of the object; processing the amplitude to find a corrected amplitude using the determined characteristic; and calculating the coordinates based on the corrected amplitude.
Claim 4
Dependent Claim
68 words
A method in accordance with claim 2, wherein determining the characteristic of the induced energy fields comprises: receiving a first signal responsive to the energy field in the absence of the field-responsive article; introducing the article into the vicinity of the object; receiving a second signal responsive to the energy field in the presence of the article; and processing the first and second signals to determine the characteristic.
Claim 5
Dependent Claim
67 words
A method in accordance with claim 3, wherein processing the first and second signals comprises: finding a first amplitude A and a first phase φ of the first signal; finding a second amplitude and a second phase φ total of the second signal; and determining a phase shift φ', associated with the induced field, based on the first and second amplitudes and the first and second phases.
Claim 6
Dependent Claim
34 words
A method in accordance with claim 4, wherein determining the phase shift φ' comprises finding values of φ' and of a third amplitude A' associated with the induced field, substantially as given by: ##EQU4##
Claim 7
Dependent Claim
58 words
A method in accordance with claim 5, wherein determining spatial coordinates comprises: measuring an uncorrected amplitude I and an uncorrected phase φ un of the signals received at one of the plurality of locations of the object; finding a corrected amplitude A cor , using the phase shift φ'; and calculating the coordinates based on the corrected amplitude.
Claim 8
Dependent Claim
17 words
A method in accordance with claim 6, wherein the corrected amplitude is substantially as given by: ##EQU5##
Claim 9
Dependent Claim
33 words
A method in accordance with claim 7, and comprising detecting a malfunction in a system for tracking the object by finding a variability in one or more of the first and second phases.
Claim 10
Dependent Claim
19 words
A method in accordance with claim 8, wherein the characteristic is not determined from measurements made at the location.
Claim 11
Dependent Claim
24 words
A method in accordance with claim 1, and comprising detecting the second energy field and notifying a user that the article has been introduced.
Claim 12
Dependent Claim
29 words
A method in accordance with claim 10, wherein determining the spatial coordinates of the object comprises estimating an error bound on the coordinates in the presence of the article.
Claim 13
Dependent Claim
16 words
A method in accordance with claim 11, wherein producing the energy fields comprises producing magnetic fields.
Claim 14
Dependent Claim
23 words
A method in accordance with claim 12, wherein receiving the signals comprises receiving electrical signals which are generated responsive to the magnetic field.
Claim 15
Dependent Claim
92 words
An object tracking system, comprising: a radiator, which generates an energy field in the vicinity of the object; a sensor, fixed to the object, which generates signals responsive to the energy field; and signal processing circuitry, which receives the signals from the sensor and determines position coordinates of the object responsive thereto, while detecting interference in the signals due to introduction into the vicinity of the object of an article responsive to the energy field wherein the circuitry detects a phase shift in the signals due to the introduction of the article.
Claim 16
Dependent Claim
92 words
An object tracking system, comprising: a radiator, which generates an energy field in the vicinity of the object; a sensor, fixed to the object, which generates signals responsive to the energy field; and signal processing circuitry, which receives the signals from the sensor and determines position coordinates of the object responsive thereto, while detecting interference in the signals due to introduction into the vicinity of the object of an article responsive to the energy field wherein the circuitry detects a phase shift in the signals due to the introduction of the article.
Claim 17
Dependent Claim
26 words
A system according to claim 14, wherein based on the detected phase shift, the circuitry corrects the position coordinates for errors induced due to the interference.
Claim 18
Dependent Claim
23 words
A system according to claim 15, wherein the circuitry detects a malfunction in the system by finding a variability in the phase shift.
Claim 19
Dependent Claim
26 words
A system according to claim 16, wherein the circuitry notifies a user of the system that the article has been introduced, based on the detected interference.
Claim 20
Dependent Claim
21 words
A system according to claim 17, wherein the circuitry determines an error bound on the coordinates, based on the detected interference.
Claim 21
Dependent Claim
27 words
A system according to claim 18, wherein the energy field comprises a magnetic field, and wherein the signals comprise electrical currents generated responsive to the magnetic field.
References Cited (Backward Citations)
US3644825A
Cited
US3868565A
Cited
US4017858A
Cited
US4054881A
Cited
US4287809A
Cited
US4317078A
Cited
US4710708A
Cited
US4416289A
Cited
US4560930A
Cited
US4613866A
Cited
US4526177A
Cited
US4642786A
Cited
US4651436A
Cited
US4945305A
Cited
US4849692A
Cited
US5002137A
Cited
US4905698A
Cited
US4905698B1
Cited
US5099845A
Cited
US5042486A
Cited
US5068608A
Cited
US5273025A
Cited
US5253647A
Cited
US5172056A
Cited
WO1992003090A1
Cited
US5429132A
Cited
US5269289A
Cited
US5377678A
Cited
US5255680A
Cited
US5251635A
Cited
US5265610A
Cited
US5211165A
Cited
US5425367A
Cited
US5437277A
Cited
US5325873A
Cited
WO1994004938A1
Cited
US5375596A
Cited
US5309913A
Cited
US5453687A
Cited
WO1994023647A1
Cited
US5443489A
Cited
US5694945A
Cited
US5425382A
Cited
US5622169A
Cited
US5558091A
Cited
WO1996005768A1
Cited
US5577502A
Cited
US5752513A
Cited
WO1996041119A1
Cited
US5729129A
Cited
US5715822A
Cited
US5682886A
Cited
WO1997029679A2
Cited
WO1997029709A1
Cited
WO1997029678A2
Cited
WO1997029710A1
Cited
US5769843A
Cited
WO1997032179A1
Cited
WO1997042517A1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2003-11-14 | 2004-05-15 | 2004-11-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2007-11-14 | 2008-05-15 | 2008-11-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2011-11-14 | 2012-05-15 | 2012-11-14 | $7700.00 | Window Closed / Lapsed |