Patent EP0354759A2 successfully refreshed from Google Patents.
EP0354759A2
Expired / Lapsed
EP
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Electromagnetic identification system
Assignee: Central Research Laboratories Ltd
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Filing: 1989-08-08
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Granted: —
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Expires: 2009-08-08
Abstract
Abstract A tag for use with an electromagnetic identification system includes a magnetic control component (1), having alternating regions (10, 20) of, respectively, high and medium coercivity material, and an element (30) of magnetically soft material. The element (30) may be polarised so as to deactivate the tag by, for example, selectively demagnetising the regions (20) of medium coercivity, such as by exposing the tag to an alternating magnetic field having an initial field strength which is intermediate between the coercivity of the regions (10, 20), which may be formed as a striped coating or from a number of discrete magnetic components. The tag may include a surface layer bearing information (60) so as, for example, to simulate a product label.
Inventors
- 👤 David John Sansom
- 👤 Simon Nicolas Murray Willcock
- 👤 Robert Alex Woolley
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-01 11:02
CPC Classifications
G; G08; G08B; G08B13/00; G08B13/22; G08B13/24; G08B13/2402; G08B13/2405; G08B13/2408; G08B13/2411; G06; G06K; G06K19/00; G06K19/06; G06K19/06187; G08B13/2414; G08B13/2417; G08B13/2428; G08B13/2437; G08B13/2442
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
60 words
A tag for use with an electromagnetic identification system, the tag comprising an element of magnetically soft material and, in magnetic communication therewith for enabling polarisation of the element, a magnetic control component including first and further regions having, respectively, first and further magnetic characteristics for enabling magnetisation or demagnetisation of first or further regions independently of the other regions.
Claim 2
Dependent Claim
60 words
A tag for use with an electromagnetic identification system, the tag comprising an element of magnetically soft material and, in magnetic communication therewith for enabling polarisation of the element, a magnetic control component including first and further regions having, respectively, first and further magnetic characteristics for enabling magnetisation or demagnetisation of first or further regions independently of the other regions.
Claim 3
Dependent Claim
16 words
A tag according to Claim 1 wherein the first and further magnetic characteristics comprise magnetic coercivity.
Claim 4
Dependent Claim
48 words
A tag according to Claim 2 wherein the first regions of the magnetic control component comprise cobalt doped iron oxide, thereby to provide regions of relatively high coercivity, and the further regions of the magnetic control component comprise gamma iron oxide, thereby to provide regions of medium coercivity.
Claim 5
Dependent Claim
16 words
A tag according to Claim 1 wherein the first and further magnetic characteristics comprise Curie temperature.
Claim 6
Dependent Claim
21 words
A tag according to any one of the preceding claims wherein the element of magnetically soft material is of strip form.
Claim 7
Dependent Claim
21 words
A tag according to any one of the preceding claims wherein the element of magnetically soft material comprises a permalloy film.
Claim 8
Dependent Claim
16 words
A tag according to Claim 6 wherein the permalloy film is supported by a copper foil.
Claim 9
Dependent Claim
36 words
A tag according to any one of the preceding claims wherein the magnetic control component comprises a coating of magnetic material having, respectively, the first and further magnetic characteristics in the first and further regions thereof.
Claim 10
Dependent Claim
39 words
A tag according to any one of Claims 1 to 7 wherein the first and further regions of the magnetic control component comprise first and further discrete components of magnetic material having, respectively, the first and further magnetic characteristics.
Claim 11
Dependent Claim
17 words
A tag according to any one of the preceding claims comprising a boundary layer for displaying information.
Claim 12
Dependent Claim
31 words
A tag according to any one of the preceding claims comprising a substrate for supporting the tag and/or for enabling the tag to be attached to an item to be surveilled.
References Cited (Backward Citations)
No citation records indexed.
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