Patent US3775305A successfully refreshed from Google Patents.
US5889271A
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Method of reading a security thread
Assignee: Bank of England
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Filing: 1995-11-07
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Granted: 1999-03-30
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Expires: 2015-11-07
Abstract
Abstract A security thread detector assembly for reading a security thread carried by a security document and coded such that each of a succession of segments along the thread represents a digital value, the particular digital value being represented by the particular characteristic of the respective segment comprises a head having a multiplicity of parallel reading channels having a track pitch which is substantially less than the length of a segment and being disposed to read the document such that the thread is substantially broadside to the channels, whereby all the segments are sensed substantially simultaneously and each segment is represented by a plurality of samples.
Inventors
- 👤 Martin John Webb
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 05:28
CPC Classifications
G; G07; G07D; G07D7/00; G06; G06K; G06K7/00; G06K7/08; G06K7/082; G06K7/083; G06K7/084; G07D7/004
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
158 words
A method of reading a security thread carried by a security document and coded such that each of a succession of segments along the thread represents a digital value, each digital value being represented by the characteristic of the segment, the method comprising the steps of providing a multiplicity of side-by-side reading channels having a track pitch which is substantially less than the length of a segment, presenting the document such that the thread is substantially broadside to the channels so that all of the segments which are to be sensed are sensed substantially simultaneously, representing each sensed segment by a plurality of samples, applying to at least one group of samples a numerical criterion of tolerances such that any segment may be validly represented by more than or fewer than a nominal number of samples, the nominal number corresponding to said plurality of samples and being at least four, and detecting a code represented by the segments.
Claim 2
Independent Claim
158 words
A method of reading a security thread carried by a security document and coded such that each of a succession of segments along the thread represents a digital value, each digital value being represented by the characteristic of the segment, the method comprising the steps of providing a multiplicity of side-by-side reading channels having a track pitch which is substantially less than the length of a segment, presenting the document such that the thread is substantially broadside to the channels so that all of the segments which are to be sensed are sensed substantially simultaneously, representing each sensed segment by a plurality of samples, applying to at least one group of samples a numerical criterion of tolerances such that any segment may be validly represented by more than or fewer than a nominal number of samples, the nominal number corresponding to said plurality of samples and being at least four, and detecting a code represented by the segments.
Claim 3
Dependent Claim
34 words
A method according to claim 1 wherein the document is rectangular and the thread is parallel to shorter sides of the document, and including presenting the document with one of the shorter sides leading.
Claim 4
Dependent Claim
16 words
A method according to claim 1 wherein the group of samples represents a multiplicity of segments.
Claim 5
Dependent Claim
29 words
A method according to claim 1 wherein the samples of a plurality of groups are examined and the digits representing the same binary value within a group are counted.
References Cited (Backward Citations)
US3978450A
Cited
GB2098768A
Cited
US5093184A
Cited
EP0413534A1
Cited
US5279403A
Cited
US5419424A
Cited
US5631039A
Cited
US5757521A
Cited
US5786910A
Cited
US5614824A
Cited
US5736722A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2002-03-29 | 2002-09-28 | 2003-03-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-03-29 | 2006-09-28 | 2007-03-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-03-29 | 2010-09-28 | 2011-03-30 | $7700.00 | Window Closed / Lapsed |