Registers – Systems controlled by data bearing records – Credit or identification card systems
Patent
1994-09-06
1996-09-17
Hajec, Donald T.
Registers
Systems controlled by data bearing records
Credit or identification card systems
235491, G06K 500
Patent
active
055570852
DESCRIPTION:
BRIEF SUMMARY
TECHNICAL FIELD
The invention relates to an electronic identification device and a method in such a device. By means of said identification device it is possible to detect presence of objects in an interrogation zone and also the identity of said objects. The detection is made contactless.
PRIOR ART
For a long time so called transponders functioning as electronic identification devices have been used in a variety of areas. Such a transponder comprises some type of means that is affected by an external signal to transmit or respond with another signal. Said external signal is generated by a transmitter means transmitting said signal within a specific area, a so called interrogation zone. Normally the reply signal includes such information that the transmitter means or a receiver means operatively connected thereto will be informed that the transponder is present in the interrogation zone. The information may exist in form of a specific reply frequency from an oscillator circuit on said transponder or by such influence of the external signal that the transmitter means can identify the transponder.
In agriculture this type of transponder has been used to identify specific animals in a group of animals. In these applications the transponder is attached to some part of the body of the animal, for instance the ear, and the response signal from the transponder is used for instance for portioning out food and for administrating drugs. There are also transponders, the reply signal thereof including besides the identification signal also information about for instance the body temperature of the animal.
Latter developments of microtechniques have made possible further developed transponders including an arithmetic unit and a memory unit having a considerably calculating and memory capacity. In such embodiments the reply signal can be far more complex and comprise large amounts of information taken for instance from said memory unit. It is possible also to transmit to said transponder information to be stored in the memory unit thereof. A transponder of this type is disclosed in W091/17515.
Normally a transponder is formed so that the reply signal thereof differs from the reply signal of other transponders. One of the most common applications for transponders is exactly to identify which bodies or which objects that carry the transponder. Identical objects normally carry identical transponders, that is transponders that are adjusted to transmit the same reply signal. In such cases problems arise if a plurality of identical objects at the same time are located in the interrogation zone where they will be reached by the external signal.
SUMMARY OF THE INVENTION
An object of the present invention is thus to overcome this problem and to allow identification or separation of a plurality of identical objects in said interrogation zone, and also to make possible collection of completing information about the object, for instance the position or orientation thereof in the interrogation zone. The object will be achieved by using elements which are produced by materials, the magnetic or magnetomechanical properties thereof depending on and being influenced by an external magnetic field. According to the invention preferrably sensors made of so called amorphous material are used but also other materials having similar magnetic properties can be used. It is possible also to use other sensors, the electrical or magnetical properties thereof being altered by external magnetic fields. Such sensors are for instance magnetoresistive sensors, that is sensors in which the electrical conductivity being changed in dependence of magnetic fields, and magnetooptical sensors, that is sensors in which the light conductivity is changed in dependence of an applied magnetic field. Sensors made of the latter type may use for instance the phenomenon referred to as the FARADAY EFFECT, that is that the oscillation plane of polarized light is pivoted, the pivoting angle being proportional to the magnetic field strength, or the phenomonen refer
REFERENCES:
patent: 4071818 (1978-01-01), Krisst
patent: 4168496 (1979-09-01), Lichtblau
patent: 4388524 (1983-06-01), Walton
patent: 4399437 (1983-08-01), Falck et al.
patent: 4459474 (1984-07-01), Walton
patent: 4495496 (1985-01-01), Miller, III
patent: 4510490 (1985-04-01), Anderson, III et al.
patent: 4584577 (1986-04-01), Temple
patent: 4600829 (1986-07-01), Walton
patent: 4647917 (1987-03-01), Anderson, III et al.
patent: 4656463 (1987-04-01), Anders et al.
patent: 4727360 (1988-02-01), Ferguson et al.
patent: 4940966 (1990-07-01), Pettigrew et al.
patent: 4980670 (1990-12-01), Humphrey et al.
patent: 5001458 (1991-03-01), Tyren et al.
patent: 5099225 (1992-03-01), Narlow et al.
patent: 5111186 (1992-05-01), Narlow et al.
patent: 5406262 (1995-04-01), Herman et al.
Persson Leif A.
Tyren Carl
Hajec Donald T.
RSO Corporation N.V.
Wigmore Steven
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