WO2020011308A1

WO2020011308A1 - Magnetic head and method for storing information, and product

Info

Publication number: WO2020011308A1
Application number: PCT/DE2019/100628
Authority: WO
Inventors: Mathias Rechel; Piriya TAPTIMTHONG; Marc Christopher Wurz
Original assignee: Gottfried Wilhelm Leibniz Universität Hannover
Priority date: 2018-07-12
Filing date: 2019-07-04
Publication date: 2020-01-16
Also published as: DE102018116896A1; EP3821431A1

Abstract

The invention relates to a magnetic head (1) having at least one magnetic flux guide (2) with at least two co-operating pole shanks (3), wherein the pole shanks (3) have pole shank ends (4) facing one another and a working gap (5) is formed between the pole shank ends (4) facing one another. The magnetic head (1) further has at least two flux guides (2) which each have a working gap (5), and/or a pole shoe (6) having at least two pole structures (7, 7') is formed on the pole shank end (4) of at least one of the co-operating pole shanks (3), each of which pole structures forms a partial working gap (8, 8') with the co-operating pole shank (3). The invention further relates to a method for magnetically storing information in a storage medium and to a product having information magnetically stored in the product.

Description

Magnetic head and method for storing information and product

The invention relates to a magnetic head, having at least one magnetic head

River guidance with at least two interacting pole legs, the

Pole legs have mutually facing pole leg ends and a working gap is formed between the facing pole leg ends. The invention further relates to a method for magnetic storage of information in one

Storage medium and a product with information magnetically stored in the product.

The need for methods to make the origin of a component traceable has been in constant growth for several years. This is particularly important with regard to the determination of components from a third-party manufacturer which do not meet the qualitative requirements for the properties of the components of an original equipment manufacturer, but which cannot be easily distinguished from one another due to their identical design.

In the area of article identification, bar codes or bar codes known from US Pat. No. 2,612,994 A have been affixed to or on articles since the 1970s - in particular to simplify a checkout process - by means of which a simple

Machine readability of a unique article number assigned to a respective article can be realized. On the one hand there is z. B. the possibility of such bar or bar codes as inexpensive one-way marking on an article or a component or on the other hand such a bar or bar code inseparable in the component. The latter case can be carried out, inter alia, by means of an engraving and in particular by means of a laser engraving, as is disclosed by WO 01/39 108 A2. In this way, however, it is just as practical to insert information into a component in a form other than a barcode or barcode. To identify an article or component marked with a bar or bar code, however, the bar or bar code must be recorded directly, which regularly requires a small distance of a few centimeters from a reader. In addition to barcodes or barcodes, RFID (radio-frequency identification) tags have been established, particularly in the industrial environment, by means of which one

Identification, inventory control and transport route control of articles or components is possible even over greater distances of up to several meters.

However, the identification of components by means of these methods is disadvantageous in that the information assigned to a component in this way is not hidden, but is essentially obviously recognizable. There is also a lack of the possibility of changing or supplementing information while at the same time being inseparable from the component.

As a result, methods are to be regarded as advantageous which enable the information used to identify a component to be supplemented or changed, and which at the same time are inseparable from the storage medium containing the information and the component.

Such a possibility is described by DE 10 2012 022 894 A1, the publication disclosing a projectile which has a storage unit arranged within it for the unique identification of the projectile. Among other things, it is also shown that information can be magnetically introduced into this storage unit.

Magnetic storage of data in or on storage media

Components in the broader sense are both in analog and therefore continuous in terms of value and time, and in digital form, and consequently in a manner that is discrete in value and generally also time

well known. As a representative of the former storage technology or components in the broader sense, z. B. Sound carriers with magnetic tapes as a storage medium in the form of classic 8-track cassettes or the more modern compact audio cassette. The second-mentioned storage technology has been widely used in mass data storage devices such as hard disk drives. Obviously, however, the goal of storage in the component - thus the corresponding storage medium - is to store the data, in particular a large amount of data per se, and not to enable the component itself to be identified as a result.

When magnetic tapes are used as the storage medium, information is usually stored by means of a toroidal core head which comes into contact with the magnetic tape. As described by way of example by US 2 948 488 A, it is within the scope of the writing process necessary to guide and stretch the magnetic tape in such a way that reliable contact with the writing head is ensured.

In the area of hard disk drives, on the other hand, due to the required high data density and thus a small size of individual data bits, so-called

Thin-film heads, as described, inter alia, in US Pat. No. 4,819,111 or US Pat. No. 5,898,541, the manufacture of which is based on technologies of microsystem technology and microelectronics. These thin-film heads comprise a missile, which on its underside facing the writing medium of the hard disk drive has a z. B. by US 8 593 764 B1 structuring, whereby an air cushion and thus a defined distance between the rotation of the writing medium

Thin film head and the writing medium is generated. This enables one

reliable, contactless writing process.

As already mentioned, there is an inevitable connection with an increase in the storage density to reduce the extent of a data bit. Such a reduction can be achieved by reducing the size of the data bits writing

Thin film head. However, this downsizing means that the

Thin film head generated magnetic field strength decreases. A condition to be taken into account contrary to this is that, along with the reduction in the extent of the data bits, magnetic storage media are required which have a high magnetic moment and a high coercive field strength. This is due to the fact that magnetic materials and thus the storage media made of them regularly have a grain structure and, when the data bit extent is reduced, a smaller number of such grains - down to just one grain - represent a data bit. Magnetic materials, which have low coercive field strengths and could therefore easily be remagnetized to represent the bit values zero and one with reduced thin-film heads, would be subject to spontaneous demagnetization and thus data loss if the data bit extent were reduced due to the superparamagnetic effect.

To circumvent this problem, WO 2005/034 093 A1 discloses a thin-film head which has a transducer element which is used to generate thermal radiation. Such a distinctive thin-film head uses the so-called heat-assisted magnetic recording (HAMR) process. This method enables the local heating of a magnetic storage medium to a temperature near or above its Curie temperature, which Magnetization of the storage medium with low magnetic field strengths and thereby to be achieved well below its coercive field strength.

However, the methods described for magnetic storage of information on magnetic tapes or hard drives are only suitable to a limited extent

Storage of information on virtually any component. The print heads used are not flexible and therefore cannot adapt to the surface of the component. On the other hand, either the flexible storage medium has to lie against the write head or the write head and storage medium are aligned with a minimum distance of a few nanometers from one another. Both are with regard to one

Saving on a component is not practical. In addition, the magnetic materials used in the writing heads in the form of iron alloys are susceptible to vibrations due to their mechanical properties and to an increased level during operation

Exposed to wear. Because of this, there is usually an encapsulation of the

Print heads, which however cannot be replaced easily.

A major disadvantage of the above-mentioned method-overcoming method and a device by means of which information can be introduced into a component using magnetic storage technology is described by P. Taptimthong, JF Düsing, L. Rissing and MC Wurz in the context of the publication “Flexible magnetic reading / writing system: heat-assisted magnetic recording ”in Procedia Technol. 26 (2016), pages 72-78. The document discloses a magnetic write head of the type mentioned at the beginning, by means of which data bits can be inserted into a component. The magnetic writing head has a flexible flow guide, which comes into contact with the surface of the component to be written during a writing operation. In addition, the magnetic writing head has a laser source and a lens system which serves to focus a laser beam generated by the laser source onto the surface of the component. By means of the disclosed

Magnetic write head, it is thus possible to represent a respective data bit both without and with the method of heat-supported magnetic recording

To magnetize the material of the component itself or a magnetic material inserted into the component. A disadvantage of this is the fact that simply introducing information in digital form - that is, generating data bits representing information in the component - is not sufficient

Offers counterfeit security. It is conceivable that due to the comparatively simple writing process of data bits on a component of an original equipment manufacturer

Information can be read out and transferred to a component from a third-party manufacturer. Against this background, the object of the invention is to provide a magnetic head of the type mentioned at the beginning, by means of which information can be introduced into a magnetic storage medium with increased security against counterfeiting or counterfeiting. The invention is also based on the object of providing a method which is used to introduce information into a magnetic storage medium with increased security against counterfeiting or counterfeiting. In addition, the object is also to provide a product with information magnetically stored in the product, information with increased security against counterfeiting or counterfeiting being stored in the product.

The first-mentioned object is achieved according to the invention with a magnetic head according to the

Features of claim 1 solved.

The further embodiment of the invention can be found in the subclaims.

According to the invention, a magnetic head is therefore provided, in particular for the magnetic storage of information on or in a magnetic storage medium, which has at least one, in this case in particular elastic, magnetic flux guidance, each with at least two interacting pole legs. The pole pieces have mutually facing - and in particular spaced - pole piece ends, a working gap being formed between the facing pole piece ends. In a first variant of the magnetic head according to the invention, it is now provided that the magnetic head has at least two flux guides, each with a working gap. On the other hand, there is a second - preferred - variant of the

Magnetic head according to the invention in that at the pole leg end of at least one of the interacting pole legs - a flux guide - a pole piece is formed with at least two pole structures, each of which forms a partial working gap with the interacting pole leg. It should be noted, however, that such a pole piece should preferably be formed on each of the interacting pole pieces. Furthermore, a combination of the first and the second variant of the magnetic head according to the invention is also provided, so that, for. B. there is a magnetic head with two flux guides, at their respective pole leg ends a pole piece is formed.

By means of the variants of the magnetic head according to the invention it is possible for at least two spatially separated,

individual magnetic structures can be introduced into the magnetic storage medium, wherein the magnetic storage medium can also be a product - such as a component - itself or part of a product. Such patterns result in increased counterfeiting and counterfeiting security, particularly in the area of counterfeit protection. The in

Storage medium generated and the magnetic pattern forming magnetic

Individual structures can be of identical design or differ in their geometric shape and / or size, the shape and / or size depending, among other things, on the geometric configuration of the pole structures forming the pole shoes.

Furthermore, the simultaneous introduction is to be understood in particular as the generation of the magnetic individual structures within a writing process, especially without a change in position of the magnetic head relative to the storage medium. Such a writing process - i.e. the introduction of one or more individual magnetic structures into the storage medium - includes, among other things, the excitation and thus a current flow through at least one excitation coil, as a result of which a magnetic field and thus a magnetic flux is generated in the flux guide or the flux guides.

As previously noted, the flow guide or the flow guides are preferably elastic and thus flexible and pliable. B. allows an adaptation of the elastic flow to the geometry of the surface of the magnetic storage medium. The elasticity of the flow guide results from the production of the flow guide or guides by reshaping a film, for example by folding or folding, and the associated creation of fold lines or fold edges in the film. Furthermore, this film consists of a semi-finished product, in the present case consisting of a thin-layer carrier and a likewise thin-layer lamination of a soft magnetic material. By structuring this soft magnetic material, e.g. B. by subtractive

Manufacturing methods such as etching are shaped on the carrier to form a structure that actually guides the magnetic flux. An elastic flow guide thus consists at least of the carrier and an actual flow-guiding structure made of soft magnetic material formed on the carrier. The soft magnetic material can z. B. an alloy of nickel iron or cobalt iron, the carrier

Plastic, preferably polyimide. The elastic flow guide should have at least three sections, of which two sections are flat and a section formed between these two flat sections has a curvature, in particular a convex curvature formed in the direction of the storage medium during operation of the magnetic head. In addition, an embodiment of the flexible flow guidance is possible with a further section opposite the section having a curvature, which section in the

Is essentially flat and in which the working gap faces away End sections of the flow guide or the pole limbs overlap or abut one another in abutting fashion.

With regard to the use of a plurality of elastic flux guides in the magnetic head, it is thus conceivable that these elastic flux guides, each separately consisting of numerically a carrier and numerically a flow-guiding structure, or consisting of numerically a carrier and several — thus at least two — separately structured on this carrier flow-guiding structures are embodied.

In a particularly advantageous development of the invention, a respective pole piece - in particular three - has at least two pole structures in their basic shape

differing groups of pole structures, with the differing geometric basic shape of the pole structures being able to influence the geometric shape of individual magnetic structures to be produced in a direct connection.

As a result, depending on the number of different groups, at least two different magnetic individual structures in the

Create storage medium, which in turn form a specific, magnetic pattern. In addition, the formation of the pole structures in a differing basic shape and a resulting differentiated configuration of the partial working columns corresponding to the pole structures result in the possibility of generating magnetic ones

Control individual structures in the storage medium. The different basic forms, in connection with a magnetic flow caused by the current flow through one or more excitation coils, lead to differing levels

Magnetic flux densities in the pole structures of different groups and hereby

coherently differing magnetic field strengths in the

corresponding sub-working columns. By varying the current flow through the excitation coil or a number of excitation coils, it is thus possible in a targeted manner to generate a magnetic field strength in certain partial working columns, which has a height which is sufficient to cause magnetization or remagnetization of the storage medium, whereas such a magnetic field strength is not sufficient in other partial working columns is.

Another extremely profitable embodiment of the magnetic head is also present when at least two pole structures of a first group are formed on at least one pole structure of a second group. Here, the first group should contain pole structures, which are present as pole fingers with a triangular base. Pole structures, which, however, are preferred as pole tongues with a trapezoidal base area are designed as an isosceles trapezoid, should also be assigned to the second group. A pole piece formed by the pole structures of these groups would, for example, be designed in such a way that a pole finger is arranged on each of the two opposite legs of a pole tongue that converge in the direction of the working gap between interacting pole legs, the pole fingers extending normally to the respective leg of the pole tongue extend into the working gap.

Advantageously, in a further development of the magnetic head, a pole piece and / or the pole pieces is formed at the pole leg end of each pole leg

interacting pole pieces are symmetrical, so that the individual magnetic structures also assume a symmetrical shape. In the case of a preferred embodiment of a flow guide with only two pole legs, their

If the pole pieces are opposite one another, it should be provided accordingly that the pole pieces formed at the ends of the pole pieces are designed to be mirror-symmetrical.

If the magnetic head for coupling heat into the storage medium also has at least one, in particular only one, at least one energy-generating radiation-generating radiation unit or if the number of radiation units generating a beam corresponds to the number of partial working columns, then it is advantageous by means of the radiation unit or the radiation units enables the process of heat-assisted magnetic recording (HAMR) to be used in order to achieve magnetization or remagnetization of individual magnetic structures below the coercive force of the magnetic material used for the magnetic storage medium by

Storage medium is heated in the areas of magnetic individual structures to be introduced to a temperature near or above the Curie temperature. Here, an irradiation unit should preferably be designed as a laser diode, which generates a laser beam in the ultraviolet, visible or infrared spectral range. By arranging one or more irradiation units, the number of which corresponds to the number of partial working columns, it would be profitable to dispense entirely with a deflection device or at least with a deflection device, which enables a variable change in the direction of travel of the beam or beams. If the flow guide is designed as an elastic flow guide with a carrier, it would be necessary that in the area of the working gap and / or at least in areas of the

Partial working gaps of one or more openings are formed in the carrier of the elastic flow guide, so that the beam or beams pass through the carrier, strike the storage medium and can thus couple heat into it. A promising embodiment of the magnetic head according to the invention is further characterized in that the magnetic head has a deflection device or a deflection device for influencing a direction of travel of the beam or a respective beam, wherein the deflection device or devices can be designed such that they are constant or on the other hand causes or causes a variable change in the course direction. If the beam is designed, for example, as a laser beam, then a constant change in the direction of travel of the beam would be brought about in a simple case by means of a deflection device, which as a at a fixed angle

Direction of travel of the beam or the beams of fixed mirrors is formed. To implement a variable deflection, however, the or a respective

Deflection device as a mirror scanner with, for example, opposite the

Direction of the beam or the beams pivotable or rotatable mirrors.

The arrangement of one or more radiation units and / or the influencing of the direction of travel of the beam by means of the deflection device or the deflection devices takes place in such a way that the area in which the beam or a respective beam is used

Support or simplification of the magnetization or remagnetization of the individual structures in the storage medium strikes the storage medium, is located in the working gap or the partial working columns and is therefore essentially orthogonal to the direction of the beam or the rays is limited by interacting pole legs and / or pole structures of interacting pole legs.

A promising further development of the magnetic head according to the invention is further characterized in that the beam or a respective beam, in particular by means of the respective irradiation unit and / or an optic arranged in or on the magnetic head, can be varied, in particular controlled or regulated, in its respective beam cross section. The beam cross section corresponds to or essentially corresponds to an area intensity profile of the respective beam. Due to the local limitation of the heating of the storage medium to the beam cross section, the structural shape follows a magnetic one that is introduced into the magnetic storage medium in such a supported manner

Single structure for magnetization or magnetization below the

Coercive field strength of the storage medium essentially the beam cross section of the beam heating the storage medium locally, as a magnetization or

Magnetic reversal of unheated areas cannot take place. This allows one high variety of shapes of the individual magnetic structures and, in connection with this, generate almost any number of different magnetic patterns in the storage medium.

In one embodiment, the magnetic head also has at least one

Damper element, which is operatively connected to the flow guide, a largely defined contact of the flow guide with the storage medium can be set and, in the case of an elastic flow guide, an undesired, excessive deformation of the elastic flow guide can be avoided. The damper element or the damper elements should or should in this case with the storage medium in operation of the magnetic head

facing section of the flow guide operatively connected, in particular be applied to this, the application of the damper element to the storage medium

corresponding section on the side of the relevant section of the flow guide facing away from the storage medium. Particularly in the case of an elastic flow guide, the section of the flow guide facing the storage medium, to which the damper element is operatively connected, could have a convex curvature in the direction of the storage medium. In addition to damping properties, the damper element can also have resilient properties and thus be present as a spring / damper element. This is e.g. B. possible if the damper element is designed as a viscoelastic damper.

In a highly practical embodiment, the flux guide is detachable and - separable from the magnetic head - arranged in the magnetic head, which enables simple exchange of the flux guide and thus a modular structure of the magnetic head.

In particular, in order to minimize saturation effects in the magnetic flux guidance, it also proves to be advantageous if in a further development of the magnetic head the magnetic head has a magnetic core that conducts magnetic flux and the flux guidance is connected in sections to this magnetic core in a flux-conducting manner. The magnetic core should only be partially closed, in particular in a U-shape, and / or essentially not elastic, but rigid.

Furthermore, if at least one distance measuring device and / or at least one force transducer is arranged on an underside of the magnetic head facing the storage medium during operation of the magnetic head, the distance and / or the contact force of the magnetic head and thus the flow guidance or guidance to and / or with the

Storage medium through continuous evaluation of the generated measurement signals by means of an evaluation device and a delivery of the magnetic head to the storage medium in Regulate the dependency of the measurement signals via one or more actuators. In one embodiment, three such distance measuring devices and / or could also be used

Force transducers can be arranged on the underside of the magnetic head, which in particular enables an equidistant alignment of the magnetic head parallel to the plane of the storage medium by matching the three distances and / or contact forces represented by the measured signals detected. The detection and regulation of the contact force between

Magnetic head and storage medium favors the setting of an optimal contact in the context of a contact-making introduction or contact writing of the

individual magnetic structures in the storage medium. Accordingly, the detection and control of the distance between the magnetic head and the storage medium favors an optimal distance between the magnetic head and the storage medium, in order to ensure that magnetic individual structures are reliably introduced into the storage medium in the context of contactless writing.

Furthermore, the second-mentioned object is achieved according to the invention with a method according to the features of claim 12.

The further embodiment of the method according to the invention is the associated one

See subclaims.

Thus, according to the invention, a method for magnetically storing information in a magnetic storage medium is provided, in particular by means of the magnetic head, at least two spatially separated individual magnetic structures forming a magnetic pattern are simultaneously introduced into the storage medium.

At the same time, this is to be understood as the generation of the individual magnetic structures within a writing process, in particular without a change in position of a magnetic head, which brings at least some of the information into the storage medium, relative to the storage medium.

Essentially two approaches are conceivable for storing the information in the sense of the method according to the invention. On the one hand, there is the possibility of introducing the information in the form of the magnetic pattern into the storage medium in the manner of a roll-to-roll process, which can also be referred to as writing or storing. The storage medium should be moved below the magnetic head relative to the latter, while the magnetic head is stationary in the plane parallel to the storage medium. On the other hand, the magnetic head should be arranged to be movable normally to the level of the storage medium and thus to the direction of advance of the storage medium Regulation of the distance and / or the contact force between the magnetic head and the storage medium is carried out. On the other hand, in particular when storing information on curved surfaces of a storage medium, it is advantageous to move the magnetic head over the curved surface and to maintain contact between the magnetic head and the storage medium by regulating the contact force.

The magnetic storage medium can be a product - such as a component - or part of the product itself. In addition to components, it is also conceivable that such a product is, for example, a bank note that contains a magnetic storage medium. Here, a magnetic pattern incorporated in this storage medium could serve as a forensic security feature which increases the security against forgery of the banknotes.

In an extremely advantageous development of the method according to the invention, the structure shape of at least one of the magnetic individual structures is represented by a

Beam cross-section of an energy-transmitting beam affects d. H. The structural shape of the respective magnetic individual structures essentially takes on the cross-sectional shape of the beam, as a result of which a large variety of shapes of the individual magnetic structures and, in connection therewith, an almost arbitrary number of different magnetic patterns can be generated in the storage medium.

In addition, one embodiment of the method can be regarded as very promising if the individual magnetic structures each generate an individual magnetic field that is dependent on the structural shape, as a result of which the magnetic pattern has an overlay field from the individual magnetic fields. In this way, the security against counterfeiting can be increased beyond measure due to a complex writing process.

The third object is achieved according to the invention with a product according to the

Features of claim 15 solved.

Thus, according to the invention, a product with information magnetically stored in the product is further provided, the product or a magnetic storage medium inherent in the product having at least two spatially separated, magnetic individual structures forming a magnetic pattern. The invention permits various embodiments. To further clarify its basic principle, embodiments are shown in the drawing and are described below. The drawing shows in

1 shows a simplified illustration of the magnetic head;

2 shows a further embodiment of the magnetic head;

3a, 3b elastic flow guides;

4a, 4b simplified sections through a magnetic head.

FIG. 1 shows a simplified representation of the magnetic head 1. This has the individual magnetic flux guide 2 with the two interacting pole legs 3, the flux guide 2 also being elastic and three sections of which can be seen. Two sections are flat, a section formed between these two flat sections having a convex curvature. A respective flat section is also inserted into a respective receiving opening 17 of the winding body 9, as a result of which the flux guide 2 is furthermore detachably and separably arranged in the magnetic head 1 from the magnetic head 1. The winding bodies 9 also serve to accommodate the excitation coils, which are not shown in this illustration. It can also

it should be provided that in addition to the flat sections of the river guide 2 in the

Receiving openings 17 flow amplifiers are arranged, which are present, for example, as sheets made of a soft magnetic material. Furthermore, between the mutually facing pole leg ends 4 of the pole legs 3 of the working gap 5 and at both pole leg ends 4 of the interacting pole legs 3, a pole piece 6 is formed from three pole structures 7, 7 ', which are also formed symmetrically to one another. The respective three pole structures 7, 7 'are divided into two pole structures 7 and one pole structure 7'. The pole structures 7, 7 'are still two in their basic form

assigned to differentiating groups, the pole structures 7 belonging to the first group and being designed as triangular pole fingers. The second group, however, is formed by the pole structures 7 ', which in this embodiment of the

Magnetic head 1 are shaped as trapezoidal pole tongues. The pole shoes 6 each formed by the pole structures 7, 7 'of these groups are thus designed such that a pole structure 7 designed as a pole finger is also arranged on the two opposite legs of the pole structures 7', each designed as a pole tongue, and tapering in the direction of the working gap 5 , which extend into the working gap 5. Between the opposing and spaced apart

Pole structures 7 thus each have a partial working gap 8, between the pole structures 7 ″ the partial working gap 8 ″. The representation of Figure 1 also shows the

Distance measuring device 15, which is arranged on the underside 14 of the magnetic head 1.

FIG. 2 shows a further embodiment of the magnetic head 1, the magnetic head 1 having the single radiation unit 11, which is designed as a laser diode and generates the laser beam 10. Furthermore, the magnetic head 1 has the deflection device 12 to influence the direction of travel R of the laser beam 10, which in turn is designed as a mirror scanner with a pivotable mirror. The laser beam 10 generated by the radiation unit 11 designed as a laser diode is also variable in its respective beam cross section by means of the optics 18 arranged in the magnetic head 1. In addition to changing the beam cross section of the laser beam 10, the optics also serve to focus the laser beam 10 onto the surface of the storage medium 13 shown in FIGS. 3a, 3b or 4a, 4b

beam-changing optics 18, the image recording unit 19 is also arranged in the magnetic head 1. This image recording unit 19 is in this case in particular designed as a camera or as an endoscope camera for observing structures of the

Storage medium 13 and thus the positioning of the magnetic head 1 relative to

Storage medium 13 to serve.

FIGS. 3a and 3b each show a similarly shaped, elastic flow guide 2, which consists of the actual flow-guiding structure 23 and the carrier 24. The respective pole legs 3 have pole shoes 6 formed at the pole leg ends 4 from the pole structures 7, 7 ', the pole structures 7, 7' as pole tongues and at the

Pole tongues arranged pole fingers are formed. The magnetic individual structures 21 which can be introduced into the storage medium 13 by this shaping of the pole shoes 6 and the magnetic patterns 20 formed from the individual structures 21 are shown in the illustration of the respective FIGS. 3a and 3b to the right of the flux guides 2. The magnetic pattern 20 shown in FIG. 3 a consists of two rectangular magnetic individual structures 21, which are formed over the one formed between the pole structures 7

Partial working column 8 are introduced into the magnetic storage medium 13. The magnetic field generated in the partial working columns 8 is here sufficiently high, even without a heat-supported magnetic recording, to bring about a magnetization of the storage medium 13. On the other hand, magnetization of the storage medium 13 is caused by the larger partial working gap 8 ′ compared to the partial working gap 8 and a smaller one Magnetic field forming height is not possible. As shown in FIG. 3b, it is only possible by means of the heat-assisted magnetic recording via a heat input of the beam 10 into the storage medium 13 in the area of the partial working gap 8 ', in this area an additional individual magnetic structure 21 into the storage medium 13

contribute. The structural shape of the magnetic individual structure 21 depends on the beam cross section of the beam 10. This is circular, as in the left representation of FIG. 3b, so that the magnetic individual structure 21 introduced is also circular. The magnetic pattern 20 in the storage medium 13 shown in the right-hand illustration in FIG.

The individual magnetic structures 21 each generate an individual magnetic field which is dependent on the structural shape, as a result of which the magnetic pattern 20 has an overlay field from the individual magnetic fields.

FIGS. 4a and 4b show simplified sections through a respective magnetic head 1, each of which has damper elements 22. By means of the

Damper elements 22 allow a defined contact of the elastic flow guide 2 with the storage medium 13 and an undesired, excessive deformation of the elastic flow guide 2 to be avoided. The damper element 22 and the

Damper elements 22 are in this case applied to the curved section of the flow guide 2 facing the storage medium 13, the damper element 22 being applied on the side of the curved section of the flow guide 2 facing away from the storage medium 13. As indicated schematically in FIG. 4b, the damper element 22 has, in addition to damping properties, also resilient properties and is thus designed as a spring / damper element. The magnetic head 1 shown in FIG. 4a also has three force transducers 16, by means of which a defined contact force between the magnetic head 1 or the flux guide 2 and the storage medium 13 can be adjusted in a controlled manner. applicant:

Gottfried Wilhelm Leibniz University of Hanover

Welfengarten 1

30167 Hanover

Our sign: UNV-LUH-116-PCT July 4th, 2019

B EZU G SZEI C H E N LI STE

1 magnetic head 16 force transducers

2 River guide 17 intake opening

3 pole legs 18 optics

4 pole leg end 19 image acquisition unit

5 working gap 20 Magnetic pattern

6 pole shoe 21 magnetic single structure

7, 7 'pole structure 22 damper element

8, 8 'partial working gap 23 flow-guiding structure

9 bobbins 24 carriers

10 beam

R direction

11 radiation unit

12 deflection device

13 storage medium

14 bottom

15 distance measuring device

Claims

Applicant: Gottfried Wilhelm Leibniz University of Hanover Welfengarten 1 30167 Hanover Our mark: UNV-LUH-116-PCT July 4th, 2019 PATE N TAN SP RÜ CHE

1. magnetic head (1), having at least one magnetic flux guide (2), each with at least two interacting pole legs (3), the pole legs (3) having mutually facing pole leg ends (4) and between the facing pole leg ends (4) a working gap (5) is formed, characterized in that the

Magnetic head (1) has at least two flux guides (2), each with a working gap (5) and / or at the pole leg end (4) of at least one of the interacting pole legs (3) a pole piece (6) with at least two pole structures (7, 7 ' ) is formed, each of which forms a partial working gap (8, 8 ') with the interacting pole leg (3).

2. Magnetic head (1) according to claim 1, characterized in that a respective pole piece (6) pole structures (7, 7 ') of at least two are in their basic shape

distinguishing groups of pole structures (7, 7 ').

3. Magnetic head (1) according to claim 1 or 2, characterized in that at least two pole structures (7) of a first group are formed on at least one pole structure (7 ') of a second group.

4. Magnetic head (1) according to at least one of the preceding claims, characterized in that at the pole leg end (4) of each pole leg (3) a pole piece (6) is formed and / or the pole pieces (6) interacting pole piece (3) symmetrically are trained.

5. Magnetic head (1) according to at least one of the preceding claims, characterized in that the magnetic head (1) at least one at least one

Radiation unit (11) generating energy-transmitting beam (10) or the number of radiation units (10) each generating a beam (10) corresponds to a number of partial working columns (8, 8 ').

6. Magnetic head (1) according to at least one of the preceding claims, characterized in that the magnetic head (1) to influence a course direction (R) of the beam (10) or a respective beam (10) a deflection device (12) or a deflection device (12).

7. Magnetic head (1) according to at least one of the preceding claims, characterized in that the beam (10) or a respective beam (10) is variable in its respective beam cross section.

8. Magnetic head (1) according to at least one of the preceding claims, characterized in that the magnetic head (1) has at least one damper element which is operatively connected to the flux guide (2).

9. Magnetic head (1) according to at least one of the preceding claims, characterized in that the flow guide (2) is detachably and separably from the magnetic head (1) in the magnetic head (1).

10. Magnetic head (1) according to at least one of the preceding claims, characterized in that the magnetic head (1) has a magnetic core carrying magnetic flux and the flux guide (2) is connected in sections with this magnetic core to conduct flux.

11. Magnetic head (1) according to at least one of the preceding claims, characterized in that at least one on an underside (14) of the magnetic head (1) facing a storage medium (13) during operation of the magnetic head (1)

Distance measuring device (15) and / or at least one force transducer (16) is arranged.

12. A method for the magnetic storage of information in a storage medium (13), characterized in that at the same time at least two spatially separated, individual magnetic structures (21) forming a magnetic pattern (20) in the

Storage medium (13) can be introduced.

13. The method according to claim 12, characterized in that the structural shape of at least one of the magnetic individual structures (21) is influenced by a beam cross section of an energy-transmitting beam (10).

14. The method according to claim 12 or 13, characterized in that the magnetic individual structures (21) are each dependent on the structural shape

Generate single magnetic field, whereby the magnetic pattern (20) has an overlay field from the individual magnetic fields.

15. Product with information magnetically stored in the product, characterized in that the product or a magnetic storage medium inherent in the product has at least two spatially separated, magnetic individual structures (21) forming a magnetic pattern (20).