Magnetic anti-theft and identification tag

    公开(公告)号:GB2313982A

    公开(公告)日:1997-12-10

    申请号:GB9710025

    申请日:1997-05-19

    Applicant: IBM

    Abstract: A magnetic anti-theft and identification tag 206 for concealing in an article such as a SIMM 115, microprocessor, memory or logic chip or board has an amorphous wire 101 and an array of magnetic elements 201 in the form of strips of foil, wire or magnetic ink. The amorphous wire 101 acts as an anti-theft element which is detectable when passing through an interrogation field and the array of elements provides identifying information in the form of a code which can be read by a sensing head 205. The array may be binary coded in various ways, for example by leaving out or magnetizing selected elements or magnetizing elements in opposite directions 203, 204. The elements may be soft elements driven by an applied local a.c. field from the sensor head. Two parallel rows of elements may be used. Various sensor heads are described, consisting of one or more small magnetic circuits coupled to one or more pickup loops. Some heads utilise the Matteucci effect. The wire 101 may form an integral part of the array for coding information.

    16.
    发明专利
    未知

    公开(公告)号:DE3876473D1

    公开(公告)日:1993-01-21

    申请号:DE3876473

    申请日:1988-03-25

    Applicant: IBM

    Abstract: A superconducting device operable at temperatures in excess of 30oK and a method for making the device are described. A representative device is an essentially coplanar SQUID device (10, 56A, 56B, 58A, 58B) formed in a single layer (12) of high-Tc superconducting material, the SQUID device (10, 56A, 56B, 58A, 58B) being operable at temperatures in excess of 60 K. High energy beams (34), for example ion beams, are used to convert selected portions (30) of the high-Tc superconductor layer (12) to nonsuperconducting properties so that the material now has both, superconducting regions (20A, 20B) and nonsuperconducting regions (30). In this manner a superconducting loop (16A, 16B, 20A, 20B) having superconducting weak links (16A, 16B) can be formed to comprise the SQUID device.

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