Tape, tape cartridge, servo pattern recording device, tape driver, tape system, detection device, inspection device, servo pattern recording method, tape manufacturing method, detection method, and inspection method

Abstract

The first servo pattern has a first position and a second position that intersect the imaginary line. The second servo pattern has a third position intersecting the imaginary line. The imaginary line is set at a position where the distance between the first position and the second position between the first servo pattern and the second servo pattern adjacent to each other in the longitudinal direction is half the distance between the first position and the third position. The width of the servo belt is set to a length such that the distance from the imaginary line to one end of the servo belt in the width direction coincides with the distance from the imaginary line to the other end of the servo belt in the width direction.

Description

Technical Field

[0001] The technology of the present invention relates to a magnetic tape, a magnetic tape cassette, a servo pattern recording device, a magnetic tape drive, a magnetic tape system, a detection device, an inspection device, a servo pattern recording method, a magnetic tape manufacturing method, a detection method and an inspection method. Background Art

[0002] In the specification of U.S. Patent Application Publication No. 2021 / 0125633, the servo pattern on the tape uses the same pattern as before, and the magnetic head of the tape drive is tilted to compensate in the width direction. The same pattern as before means that two non-parallel patterns are arranged symmetrically with respect to an imaginary line in the width direction and have the same azimuth angle and opposite directions.

[0003] In the servo pattern disclosed in U.S. Patent Application Publication No. 2021 / 0125633, servo signal non-uniformity occurs. To solve this problem, the servo pattern disclosed in U.S. Patent Application Publication No. 2022 / 0108718 is formed in a direction that rotates the conventional symmetrically arranged servo pattern, thereby suppressing the non-uniformity of the servo signal. Summary of the invention

[0004] An embodiment of the technology involved in the present invention provides a magnetic tape, a tape cassette, a servo pattern recording device, a magnetic tape drive, a magnetic tape system, a detection device, an inspection device, a servo pattern recording method, a magnetic tape manufacturing method, a detection method, and an inspection method that can help achieve high-precision reading of a servo band.

[0005] Means for solving technical problems

[0006] A first mode involved in the technology of the present invention is a magnetic tape having a servo band, wherein a plurality of servo patterns are recorded on the servo band along the long side direction of the magnetic tape, the servo pattern being at least one linear magnetized region pair, the linear magnetized region pair being a first linear magnetized region magnetized linearly and a second linear magnetized region magnetized linearly, the first linear magnetized region and the second linear magnetized region being inclined in opposite directions relative to a first imaginary straight line along the width direction of the magnetic tape, the first linear magnetized region being inclined at a steeper angle relative to the first imaginary straight line than the second linear magnetized region, the positions of both ends of the first linear magnetized region being aligned with the positions of both ends of the second linear magnetized region in the width direction of the magnetic tape, the first servo pattern and the second servo pattern being alternately arranged along the long side direction as the plurality of servo patterns on the servo band, and a plurality of servo patterns being set that crosses the plurality of servo patterns along the long side direction. The servo pattern has an imaginary line, the first servo pattern has a first position and a second position intersecting the imaginary line, the second servo pattern has a third position intersecting the imaginary line, the first position is a position where the imaginary line intersects with a first linear magnetized region of the first servo pattern, the second position is a position where the imaginary line intersects with the second linear magnetized region of the first servo pattern, and the third position is a position where the imaginary line intersects with the first linear magnetized region of the second servo pattern, the imaginary line is set at a position where a relationship that the first distance becomes half of the second distance holds, the first distance is a distance between the first position and the second position between the first servo pattern and the second servo pattern adjacent in the long side direction, the second distance is a distance between the first position and the third position, and the width of the servo band is set to a length where a distance from the imaginary line to one end of the servo band in the width direction is equal to a distance from the imaginary line to the other end of the servo band in the width direction.

[0007] A second aspect of the technology of the present invention is the magnetic tape of the first aspect, wherein the first linear magnetized region is a set of a plurality of first magnetized straight lines, the second linear magnetized region is a set of a plurality of second magnetized straight lines, the first position is a position where a first magnetized straight line located at one end in the long-side direction among a plurality of first magnetized straight lines included in a first servo pattern on an imaginary line intersects the imaginary line, the second position is a position where a second magnetized straight line located at one end in the long-side direction among a plurality of second magnetized straight lines included in the first servo pattern on the imaginary line intersects the imaginary line, and the third position is a position where a first magnetized straight line located at one end in the long-side direction among a plurality of first magnetized straight lines included in the second servo pattern on the imaginary line intersects the imaginary line.

[0008] A third aspect of the technology of the present invention is the magnetic tape of the second aspect, wherein in the servo pattern, the number of first magnetization straight lines is the same as the number of second magnetization straight lines, the number of first magnetization straight lines is different between the first servo pattern and the second servo pattern, and the number of second magnetization straight lines is different between the first servo pattern and the second servo pattern.

[0009] A fourth aspect according to the technology of the present invention is the magnetic tape according to any one of the first to third aspects, wherein a plurality of servo bands are formed at a predetermined pitch in the width direction.

[0010] A fifth aspect according to the technology of the present invention is a magnetic tape cassette comprising: the magnetic tape according to any one of the first to fourth aspects; and a casing that accommodates the magnetic tape.

[0011] A sixth aspect of the technology of the present invention is a servo pattern recording device, which includes a pulse signal generator and a servo pattern recording head, wherein the pulse signal generator generates a pulse signal, the servo pattern recording head has a gap pattern, and a magnetic field is applied from the gap pattern to a band-shaped area formed in a band shape along the long side direction of the tape on the surface of the tape in accordance with the pulse signal, thereby recording a plurality of servo patterns in the band-shaped area along the long side direction, and a servo band is formed by recording a plurality of servo patterns in the band-shaped area along the long side direction, and the gap pattern is at least one straight line area pair, one straight line area in the straight line area pair, namely, the first straight line area, and the other straight line area in the straight line area pair, namely, The second straight line region is inclined in an opposite direction to a second imaginary straight line along a direction corresponding to the width direction of the magnetic tape on the surface, the first straight line region is inclined at a steeper angle to the second imaginary straight line than the second straight line region, positions of both ends of the first straight line region and positions of both ends of the second straight line region are aligned in a direction corresponding to the width direction of the magnetic tape, the servo pattern is at least one linear magnetized region pair, the linear magnetized region pair is a first linear magnetized region magnetized linearly and a second linear magnetized region magnetized linearly, the first linear magnetized region and the second linear magnetized region are inclined in opposite directions to the first imaginary straight line along the width direction of the magnetic tape The first linear magnetized region is inclined at a steeper angle relative to the first imaginary straight line than the second linear magnetized region. With respect to the width direction of the magnetic tape, the positions of both ends of the first linear magnetized region are aligned with the positions of both ends of the second linear magnetized region. On the servo tape, as a plurality of servo patterns, the first servo pattern and the second servo pattern are alternately arranged along the long side direction. Among the plurality of servo patterns, an imaginary line is set that crosses the plurality of servo patterns along the long side direction. The first servo pattern has a first position and a second position that intersect with the imaginary line. The second servo pattern has a third position that intersects with the imaginary line. The first position is the first linear magnetized region where the imaginary line intersects with the first servo pattern. The first position is a position where the imaginary line intersects with the second linear magnetized region of the first servo pattern, the second position is a position where the imaginary line intersects with the first linear magnetized region of the second servo pattern, the third position is a position where the imaginary line intersects with the first linear magnetized region of the second servo pattern, the imaginary line is set at a position where the relationship that the first distance becomes half of the second distance holds, the first distance is a distance between the first position and the second position between the first servo pattern and the second servo pattern adjacent in the long side direction, the second distance is a distance between the first position and the third position, and the width of the servo band is set to a length where the distance from the imaginary line to one end of the servo band in the width direction is consistent with the distance from the imaginary line to the other end of the servo band in the width direction.

[0012] A seventh aspect of the technology of the present invention is a servo pattern recording device according to the sixth aspect, wherein the first linear magnetized region is a set of a plurality of first magnetized straight lines, the second linear magnetized region is a set of a plurality of second magnetized straight lines, the first position is a position where a first magnetized straight line located at one end in the long-side direction among a plurality of first magnetized straight lines included in the first servo pattern on the imaginary line intersects the imaginary line, the second position is a position where a second magnetized straight line located at one end in the long-side direction among a plurality of second magnetized straight lines included in the first servo pattern on the imaginary line intersects the imaginary line, and the third position is a position where a first magnetized straight line located at one end in the long-side direction among a plurality of first magnetized straight lines included in the second servo pattern on the imaginary line intersects the imaginary line.

[0013] The eighth aspect of the technology of the present invention is the servo pattern recording device of the seventh aspect, wherein in the servo pattern, the number of first magnetization straight lines is the same as the number of second magnetization straight lines, the number of first magnetization straight lines is different between the first servo pattern and the second servo pattern, and the number of second magnetization straight lines is different between the first servo pattern and the second servo pattern.

[0014] A ninth aspect according to the technology of the present invention is the servo pattern recording device according to any one of the sixth to eighth aspects, wherein a plurality of servo bands are formed at a predetermined pitch in the width direction.

[0015] The 10th method involved in the technology of the present invention is a tape drive, which comprises: a traveling mechanism for causing the magnetic tape involved in any one of the 1st to 4th methods to travel along a predetermined path; and a magnetic head having a plurality of servo reading elements for reading a servo pattern on the predetermined path while the magnetic tape is moved by the traveling mechanism. In the tape drive, the plurality of servo reading elements are arranged along the long side direction of the magnetic head, and the magnetic head is configured in a posture so that the long side direction of the magnetic head is inclined relative to the traveling direction of the magnetic tape.

[0016] The 11th mode involved in the technology of the present invention is a magnetic tape system, which comprises: a magnetic tape involved in any one of the 1st to 4th modes; a magnetic tape drive equipped with a magnetic head, the magnetic head having a plurality of servo reading elements for reading a servo pattern on a predetermined path in a state where the magnetic tape moves along the predetermined path, wherein the plurality of servo reading elements are arranged along the long side direction of the magnetic head, and the magnetic head is configured in a posture where the long side direction of the magnetic head is inclined relative to the moving direction of the magnetic tape.

[0017] A twelfth aspect of the present invention is a detection device including a processor, wherein the processor detects a servo signal that is a result of reading a servo pattern from a magnetic tape according to any one of the first to fourth aspects by a servo reading element using an autocorrelation coefficient.

[0018] A 13th mode involved in the technology of the present invention is a servo pattern recording method, which includes the following steps: generating a pulse signal; and applying a magnetic field from the gap pattern to a band-shaped area formed in a band shape on the surface of a magnetic tape along the long side direction of the magnetic tape by a servo pattern recording head having a gap pattern in accordance with the pulse signal, thereby recording a plurality of servo patterns in the band-shaped area along the long side direction, and forming a servo band by recording a plurality of servo patterns in the band-shaped area along the long side direction, wherein the gap pattern is at least one straight line area pair, one straight line area in the straight line area pair, namely a first straight line area, and the other straight line area in the straight line area pair, namely a second straight line area, relative to the servo band. The second imaginary straight line along the direction corresponding to the width direction of the magnetic tape on the surface is inclined in the opposite direction, the first straight line region is inclined at a steeper angle relative to the second imaginary straight line than the second straight line region, the positions of both ends of the first straight line region and the positions of both ends of the second straight line region are aligned in the direction corresponding to the width direction of the magnetic tape, the servo pattern is at least one linear magnetized region pair, the linear magnetized region pair is a first linear magnetized region magnetized in a linear shape and a second linear magnetized region magnetized in a linear shape, the first linear magnetized region and the second linear magnetized region are inclined in the opposite direction relative to the first imaginary straight line along the width direction of the magnetic tape, the first linear magnetized region The magnetized region has a steeper inclination angle with respect to the first imaginary straight line than the second linear magnetized region. With respect to the width direction of the magnetic tape, the positions of both ends of the first linear magnetized region are aligned with the positions of both ends of the second linear magnetized region. On the servo tape, as a plurality of servo patterns, the first servo pattern and the second servo pattern are alternately arranged along the long side direction. In the plurality of servo patterns, an imaginary line is set that crosses the plurality of servo patterns along the long side direction. The first servo pattern has a first position and a second position that intersect with the imaginary line. The second servo pattern has a third position that intersects with the imaginary line. The first position is where the imaginary line intersects with the first linear magnetized region of the first servo pattern. The first position is the position of the cross, the second position is the position where the imaginary line intersects with the second linear magnetized region of the first servo pattern, the third position is the position where the imaginary line intersects with the first linear magnetized region of the second servo pattern, the imaginary line is set at a position where the relationship that the first distance becomes half of the second distance holds, the first distance is the distance between the first position and the second position between the first servo pattern and the second servo pattern adjacent in the long side direction, the second distance is the distance between the first position and the third position, and the width of the servo band is set to a length where the distance from the imaginary line to one end of the servo band in the width direction is consistent with the distance from the imaginary line to the other end of the servo band in the width direction.

[0019] A fourteenth aspect according to the technology of the present invention is a magnetic tape on which a plurality of servo patterns are recorded by the servo pattern recording device according to any one of the sixth to ninth aspects.

[0020] A fifteenth aspect according to the technology of the present invention is a magnetic tape cassette comprising: the magnetic tape according to the fourteenth aspect; and a casing that houses the magnetic tape.

[0021] The 16th method involved in the technology of the present invention is a tape drive, which comprises: a moving mechanism that causes the magnetic tape involved in the 14th method to move along a predetermined path; and a magnetic head having a plurality of servo reading elements that read a servo pattern on the predetermined path while the magnetic tape is moved by the moving mechanism. In the tape drive, the plurality of servo reading elements are arranged along the long side direction of the magnetic head, and the magnetic head is configured in a posture so that the long side direction of the magnetic head is inclined relative to the moving direction of the magnetic tape.

[0022] The 17th method involved in the technology of the present invention is a magnetic tape system, which comprises: the magnetic tape involved in the 14th method; and a magnetic tape drive equipped with a magnetic head, the magnetic head having a plurality of servo reading elements for reading a servo pattern on a predetermined path in a state where the magnetic tape moves along the predetermined path. In the magnetic tape system, the plurality of servo reading elements are arranged along the long side direction of the magnetic head, and the magnetic head is configured in a posture where the long side direction of the magnetic head is inclined relative to the moving direction of the magnetic tape.

[0023] An eighteenth aspect of the present invention is a detection device including a processor, wherein the processor detects a servo signal that is a result of reading a servo pattern from the magnetic tape according to the fourteenth aspect by a servo reading element using an autocorrelation coefficient.

[0024] A 19th aspect of the technology of the present invention is a method for manufacturing a magnetic tape, comprising the steps of: recording a plurality of servo patterns on a magnetic tape according to the servo pattern recording method of the 13th aspect; and winding up the magnetic tape.

[0025] A 20th aspect of the present invention is an inspection device comprising: the detection device according to the 12th aspect or the 18th aspect; and an inspection processor for inspecting a servo band in which a servo pattern is recorded on a magnetic tape based on a servo signal detected by the detection device.

[0026] A 21st aspect of the present invention is a detection method including the step of detecting a servo signal obtained by using an autocorrelation coefficient when a servo pattern is read from a magnetic tape according to any one of the first to fourth and fourteenth aspects by a servo reading element.

[0027] A 22nd aspect of the technology of the present invention is an inspection method including the step of inspecting a servo band in which a servo pattern is recorded on a magnetic tape based on a servo signal detected by the detection method according to the 21st aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1This is a block diagram showing an example of the structure of the magnetic tape system involved in the embodiment.

[0029] Figure 2 It is a schematic perspective view showing an example of the appearance of the magnetic tape cassette according to the embodiment.

[0030] Figure 3 This is a schematic configuration diagram showing an example of the hardware configuration of the tape drive according to the embodiment.

[0031] Figure 4 This is a schematic perspective view showing an example of a manner in which a magnetic field is released from the lower side of the magnetic tape cassette according to the embodiment by a non-contact type reader / writer.

[0032] Figure 5 This is a schematic configuration diagram showing an example of the hardware configuration of the tape drive according to the embodiment.

[0033] Figure 6 This is a conceptual diagram showing an example of a state in which a magnetic head is positioned on a conventionally known magnetic tape as viewed from the surface side of the magnetic tape.

[0034] Figure 7 This is a conceptual diagram showing an example of how a conventionally known magnetic tape is viewed from the surface side of the magnetic tape before and after the width of the magnetic tape is reduced.

[0035] Figure 8 This is a conceptual diagram showing an example of a state in which a magnetic head is tilted on a conventionally known magnetic tape as viewed from the surface side of the magnetic tape.

[0036] Fig. 9 This is a conceptual diagram showing an example of a state in which the magnetic tape according to the embodiment is viewed from the surface side of the magnetic tape.

[0037] Fig.10 This is a conceptual diagram showing an example of the relationship between the geometric characteristics of an actual servo pattern and the geometric characteristics of a virtual servo pattern.

[0038] Fig.11 This is a conceptual diagram showing an example of the structure of a servo band formed on the magnetic tape according to the embodiment.

[0039] Fig.12 This is a conceptual diagram showing an example of a state in which corresponding frames between servo bands adjacent in the width direction of the magnetic tape according to the embodiment are shifted at a predetermined interval, as viewed from the surface side of the magnetic tape.

[0040] Fig.13 This is a conceptual diagram showing an example of a state in which a servo pattern is read by a servo read element included in a magnetic head that is not deflected on the magnetic tape according to the embodiment, as viewed from the surface side of the magnetic tape.

[0041] Fig.14 This is a conceptual diagram showing an example of a state in which a servo pattern is read by a servo read element included in a magnetic head tilted on the magnetic tape according to the embodiment, as viewed from the surface side of the magnetic tape.

[0042] Fig.15 This is a conceptual diagram showing an example of the functions of a control device included in the tape drive according to the embodiment.

[0043] Fig.16 This is a conceptual diagram showing an example of processing contents of a position detection unit and a control unit included in a control device in a tape drive according to an embodiment.

[0044] Fig.17 This is a conceptual diagram showing an example of the structure of the servo writer according to the embodiment.

[0045] Fig.18 The present invention is a conceptual diagram showing an example of the relationship between a pulse signal generator and a servo pattern recording head included in a servo writer according to an embodiment and an example of a state in which the servo pattern recording head included in the servo writer according to an embodiment is located on a magnetic tape as viewed from the surface side of the magnetic tape (i.e., the back side of the servo pattern recording head).

[0046] Fig.19 This is a conceptual diagram showing an example of a state in which a servo pattern recording head included in the servo writer according to the embodiment is located on a magnetic tape as viewed from the front side of the magnetic tape (that is, the back side of the servo pattern recording head).

[0047] Fig. 20 This is a conceptual diagram showing an example of the relationship between the geometric characteristics of an actual gap pattern and the geometric characteristics of a virtual gap pattern. DETAILED DESCRIPTION

[0048] Hereinafter, an example of an implementation of a magnetic tape, a tape cassette, a servo pattern recording device, a tape drive, a tape system, a detection device, an inspection device, a servo pattern recording method, a magnetic tape manufacturing method, a detection method, and an inspection method involved in the technology of the present invention will be described according to the accompanying drawings.

[0049] First, the words and phrases used in the following description are explained.

[0050] CPU is the abbreviation of "Central Processing Unit". RAM is the abbreviation of "Random Access Memory". NVM is the abbreviation of "Non-volatile memory". EEPROM is the abbreviation of "Electrically Erasable and Programmable Read Only Memory". SSD is the abbreviation of "Solid State Drive". HDD is the abbreviation of "Hard Disk Drive". ASIC is the abbreviation of "Application Specific Integrated Circuit". FPGA is the abbreviation of "Field-Programmable Gate Array". PLC is the abbreviation of "Programmable Logic Controller". IC is the abbreviation of "Integrated Circuit". RFID is the abbreviation of "Radio Frequency Identifier". BOT is the abbreviation of "Beginning Of Tape". EOT is the abbreviation for "End Of Tape". UI is the abbreviation for "User Interface". WAN is the abbreviation for "Wide Area Network". LAN is the abbreviation for "Local Area Network". TDS is the abbreviation for "Transverse Dimensional Stability".

[0051] As an example, Figure 1 As shown, the tape system 10 includes a tape cartridge 12 and a tape drive 14. The tape cartridge 12 is loaded in the tape drive 14. The tape cartridge 12 contains a magnetic tape MT. The tape drive 14 pulls out the magnetic tape MT from the loaded tape cartridge 12, and while advancing the pulled out magnetic tape MT, records data on the magnetic tape MT, or reads data from the magnetic tape MT.

[0052] In the present embodiment, the magnetic tape MT is an example of the "magnetic tape" involved in the technology of the present invention. Furthermore, in the present embodiment, the magnetic tape system 10 is an example of the "magnetic tape system" involved in the technology of the present invention. Furthermore, in the present embodiment, the magnetic tape drive 14 is an example of the "magnetic tape drive" and "detection device" involved in the technology of the present invention. Furthermore, in the present embodiment, the magnetic tape cassette 12 is an example of the "magnetic tape cassette" involved in the technology of the present invention.

[0053] Next, refer to Figure 2 to Figure 4 An example of the structure of the tape cassette 12 will be described. Figure 2 to Figure 4 In the figure, arrow A is used to indicate the loading direction of the tape cassette 12 into the tape drive 14, the direction of arrow A is set as the front direction of the tape cassette 12, and the front direction side of the tape cassette 12 is set as the front side of the tape cassette 12. In the description of the structure shown below, "front" refers to the front side of the tape cassette 12.

[0054] Furthermore, in the following description, for the sake of convenience, Figure 2 to Figure 4 In the figure, the arrow B direction perpendicular to the arrow A direction is defined as the right direction, and the right side of the tape cassette 12 is defined as the right side of the tape cassette 12. In the description of the structure shown below, "right" refers to the right side of the tape cassette 12.

[0055] Furthermore, in the following description, for the sake of convenience, Figure 2 to Figure 4 In the figure, the direction opposite to the arrow B direction is defined as the left direction, and the left side of the tape cassette 12 is defined as the left side of the tape cassette 12. In the description of the structure shown below, "left" refers to the left side of the tape cassette 12.

[0056] Furthermore, in the following description, for the sake of convenience, Figure 2 to Figure 4 In the figure, arrow C is used to indicate a direction perpendicular to arrow A and arrow B, arrow C is used to indicate the upper direction of the tape cassette 12, and the upper direction side of the tape cassette 12 is used to indicate the upper side of the tape cassette 12. In the description of the structure shown below, "upper" refers to the upper side of the tape cassette 12.

[0057] Furthermore, in the following description, for the sake of convenience, Figure 2 to Figure 4 In the embodiment, the direction opposite to the front direction of the tape cassette 12 is defined as the rear direction of the tape cassette 12, and the rear direction side of the tape cassette 12 is defined as the rear side of the tape cassette 12. In the description of the structure shown below, "rear" refers to the rear side of the tape cassette 12.

[0058] Furthermore, in the following description, for the sake of convenience, Figure 2 to Figure 4In the figure, the direction opposite to the upper direction of the tape cassette 12 is defined as the lower direction of the tape cassette 12, and the lower direction side of the tape cassette 12 is defined as the lower side of the tape cassette 12. In the description of the structure shown below, "lower" refers to the lower side of the tape cassette 12.

[0059] As an example, Figure 2 As shown, the tape cassette 12 is roughly rectangular in shape when viewed from above, and has a box-shaped shell 16. The shell 16 is an example of a "shell" involved in the technology of the present invention. The magnetic tape MT is accommodated in the shell 16. The shell 16 is made of a resin such as polycarbonate, and has an upper shell 18 and a lower shell 20. The upper shell 18 and the lower shell 20 are joined by welding (for example, ultrasonic welding) and screwing in a state where the lower peripheral surface of the upper shell 18 is in contact with the upper peripheral surface of the lower shell 20. The joining method is not limited to welding and screwing, and other joining methods may also be used.

[0060] The delivery reel 22 is rotatably accommodated inside the shell 16. The delivery reel 22 includes a reel hub 22A, an upper flange 22B1, and a lower flange 22B2. The reel hub 22A is formed in a cylindrical shape. The reel hub 22A is the axial portion of the delivery reel 22, and the axial direction is along the up and down direction of the shell 16, and is arranged in the central portion of the shell 16. The upper flange 22B1 and the lower flange 22B2 are respectively formed in an annular shape. The top view central portion of the upper flange 22B1 is fixed to the upper end portion of the reel hub 22A, and the top view central portion of the lower flange 22B2 is fixed to the lower end portion of the reel hub 22A. In addition, the reel hub 22A and the lower flange 22B2 can be integrally formed.

[0061] The magnetic tape MT is wound around the outer peripheral surface of the reel hub 22A, and the ends of the magnetic tape MT in the width direction are held by the upper flange 22B1 and the lower flange 22B2.

[0062] An opening 16B is formed on the front side of the right wall 16A of the housing 16. The magnetic tape MT is pulled out from the opening 16B.

[0063] A cartridge memory 24 is provided in the lower housing 20. Specifically, the cartridge memory 24 is accommodated in the right rear end portion of the lower housing 20. An IC chip having NVM is mounted in the cartridge memory 24. In this embodiment, a so-called passive RFID tag is used as the cartridge memory 24, and various information is read and written to the cartridge memory 24 in a non-contact manner.

[0064] Management information for managing the tape cartridge 12 is stored in the cartridge memory 24. The management information includes, for example, information related to the cartridge memory 24 (for example, information that can identify the tape cartridge 12), information related to the magnetic tape MT (for example, information indicating the recording capacity of the magnetic tape MT, information indicating the outline of the data recorded on the magnetic tape MT, information indicating the items of the data recorded on the magnetic tape MT, and information indicating the recording format of the data recorded on the magnetic tape MT), and information related to the magnetic tape drive 14 (for example, information indicating the specifications of the magnetic tape drive 14 and signals used in the magnetic tape drive 14).

[0065] As an example, Figure 3 As shown, the tape drive 14 includes a transport device 26, a magnetic head 28, a control device 30, a storage device 32, a UI system device 34, and a communication interface 35. The tape cartridge 12 is loaded into the tape drive 14 in the direction of arrow A. In the tape drive 14, the magnetic tape MT is pulled out from the tape cartridge 12 and used.

[0066] The magnetic tape MT has a magnetic layer 29A, a base film 29B and a back coating layer 29C. The magnetic layer 29A is formed on one side of the base film 29B, and the back coating layer 29C is formed on the other side of the base film 29B. Data is recorded on the magnetic layer 29A. The magnetic layer 29A contains ferromagnetic powder. As the ferromagnetic powder, for example, ferromagnetic powder commonly used in the magnetic layer of various magnetic recording media can be used. As a preferred specific example of the ferromagnetic powder, hexagonal ferrite powder can be cited. As the hexagonal ferrite powder, for example, hexagonal strontium ferrite powder or hexagonal barium ferrite powder can be cited. The back coating layer 29C is, for example, a layer containing non-magnetic powder such as carbon black. The base film 29B is also called a support, and is, for example, formed of polyethylene terephthalate, polyethylene naphthalate or polyamide. In addition, a non-magnetic layer can be formed between the base film 29B and the magnetic layer 29A. In the magnetic tape MT, the surface on which the magnetic layer 29A is formed is the front surface 31 of the magnetic tape MT, and the surface on which the back coat layer 29C is formed is the back surface 33 of the magnetic tape MT.

[0067] The tape drive 14 uses the magnetic head 28 to perform magnetic processing on the surface 31 of the magnetic tape MT. Here, magnetic processing refers to recording data on the surface 31 of the magnetic tape MT and reading data from the surface 31 of the magnetic tape MT (i.e., playing back data). In the present embodiment, the tape drive 14 uses the magnetic head 28 to selectively record data on the surface 31 of the magnetic tape MT and read data from the surface 31 of the magnetic tape MT. That is, the tape drive 14 pulls out the magnetic tape MT from the tape cassette 12, and uses the magnetic head 28 to record data on the surface 31 of the pulled out magnetic tape MT, or uses the magnetic head 28 to read data from the surface 31 of the pulled out magnetic tape MT.

[0068] The control device 30 controls the entire tape drive 14. In the present embodiment, the control device 30 is implemented by an ASIC, but the technology of the present invention is not limited to this. For example, the control device 30 may also be implemented by an FPGA and / or a PLC. Furthermore, the control device 30 may also be implemented by a computer including a CPU, a flash memory (for example, an EEPROM and / or an SSD, etc.) and a RAM. Furthermore, it may also be implemented by a combination of two or more of an ASIC, an FPGA, a PLC and a computer. That is, the control device 30 may also be implemented by a combination of a hardware structure and a software structure. In addition, in the present embodiment, the control device 30 is an example of a "processor" involved in the technology of the present invention.

[0069] The storage device 32 is connected to the control device 30, and the control device 30 writes various information to the storage device 32 and reads various information from the storage device 32. A flash memory and / or a HDD can be cited as an example of the storage device 32. The flash memory and the HDD are just examples, and any nonvolatile memory that can be mounted on the tape drive 14 may be used.

[0070] The UI system device 34 is a device having a receiving function of receiving an instruction signal indicating an instruction from a user and a prompting function of prompting information to the user. The receiving function is implemented, for example, by a touch panel, a hard key (for example, a keyboard) and / or a mouse. The prompting function is implemented, for example, by a display, a printer and / or a speaker. The UI system device 34 is connected to the control device 30. The control device 30 obtains the instruction signal received by the UI system device 34. Under the control of the control device 30, the UI system device 34 prompts various information to the user.

[0071] The communication interface 35 is connected to the control device 30. Furthermore, the communication interface 35 is connected to an external device 37 via a communication network (not shown) such as a WAN and / or a LAN. The communication interface 35 manages the transmission and reception of various information (e.g., data recorded on the magnetic tape MT, data read from the magnetic tape MT, and / or instruction signals given to the control device 30) between the control device 30 and the external device 37. In addition, as the external device 37, for example, a personal computer or a large computer can be cited.

[0072] The conveying device 26 is a device for selectively conveying the magnetic tape MT in the forward direction and the reverse direction along a predetermined path, and is provided with a feeding motor 36, a winding reel 38, a winding motor 40, and a plurality of guide rollers GR. In addition, here, the forward direction refers to the feeding direction of the magnetic tape MT, and the reverse direction refers to the rewinding direction of the magnetic tape MT. In the present embodiment, the conveying device 26 is an example of the "travel mechanism" involved in the technology of the present invention.

[0073] The feed motor 36 rotates the feed reel 22 in the tape cassette 12 under the control of the control device 30. The control device 30 controls the feed motor 36 to control the rotation direction, rotation speed, torque, etc. of the feed reel 22.

[0074] The winding motor 40 rotates the winding reel 38 under the control of the control device 30. The control device 30 controls the winding motor 40 to control the rotation direction, rotation speed, torque, etc. of the winding reel 38.

[0075] When the magnetic tape MT is wound up by the winding reel 38, the control device 30 rotates the feed motor 36 and the winding motor 40 so that the magnetic tape MT moves forward along a predetermined path. The rotation speed and torque of the feed motor 36 and the winding motor 40 are adjusted according to the speed at which the magnetic tape MT is wound up by the winding reel 38. The rotation speed and torque of each of the feed motor 36 and the winding motor 40 are adjusted by the control device 30, thereby applying tension to the magnetic tape MT. The rotation speed and torque of each of the feed motor 36 and the winding motor 40 are adjusted by the control device 30, thereby controlling the tension applied to the magnetic tape MT.

[0076] Furthermore, when the magnetic tape MT is rewound onto the feed reel 22, the control device 30 rotates the feed motor 36 and the take-up motor 40 so that the magnetic tape MT travels in the reverse direction along a predetermined path.

[0077] In the present embodiment, the tension applied to the magnetic tape MT is controlled by controlling the rotation speed and torque of the delivery motor 36 and the take-up motor 40, but the technology of the present invention is not limited thereto. For example, the tension applied to the magnetic tape MT may be controlled by using a dancer roller or by introducing the magnetic tape MT into a vacuum chamber.

[0078] The plurality of guide rollers GR are rollers for guiding the magnetic tape MT. The predetermined path, that is, the travel path of the magnetic tape MT is determined by arranging the plurality of guide rollers GR at intervals between the tape cassette 12 and the take-up reel 38 at positions across the magnetic head 28 .

[0079] The magnetic head 28 includes a magnetic element unit 42 and a carriage 44. The magnetic element unit 42 is held by the carriage 44 so as to come into contact with the running magnetic tape MT. The magnetic element unit 42 includes a plurality of magnetic elements.

[0080] The magnetic element unit 42 records data on the magnetic tape MT transported by the transport device 26, or reads data from the magnetic tape MT transported by the transport device 26. Here, the data refers to, for example, the servo pattern 58 (see Fig. 9 ) and data other than the servo pattern 58, that is, recorded in the data band DB (reference Fig. 9 ) data.

[0081] The tape drive 14 includes a non-contact reader / writer 46. The non-contact reader / writer 46 is disposed on the lower side of the tape cassette 12 loaded therein, facing the back surface 24A of the cartridge memory 24, and reads and writes information to the cartridge memory 24 in a non-contact manner.

[0082] As an example, Figure 4 As shown, the contactless read / write device 46 releases a magnetic field MF from the lower side of the tape cassette 12 toward the cartridge memory 24. The magnetic field MF penetrates the cartridge memory 24.

[0083] The contactless reader / writer 46 is connected to the control device 30. The control device 30 outputs a control signal to the contactless reader / writer 46. The control signal is a signal for controlling the cartridge memory 24. The contactless reader / writer 46 generates a magnetic field MF according to the control signal input from the control device 30, and releases the generated magnetic field MF toward the cartridge memory 24.

[0084] The contactless reader / writer 46 performs contactless communication with the cartridge memory 24 via the magnetic field MF, thereby performing processing corresponding to the control signal on the cartridge memory 24. For example, under the control of the control device 30, the contactless reader / writer 46 selectively performs processing for reading information from the cartridge memory 24 and processing for causing the cartridge memory 24 to store information (i.e., processing for writing information to the cartridge memory 24).

[0085] As an example, Figure 5 As shown, the tape drive 14 is provided with a moving mechanism 48. The moving mechanism 48 has a moving actuator 48A. As the moving actuator 48A, for example, a voice coil motor and / or a piezoelectric actuator can be cited. The moving actuator 48A is connected to the control device 30, and the control device 30 controls the moving actuator 48A. The moving actuator 48A generates power under the control of the control device 30. The moving mechanism 48 receives the power generated by the moving actuator 48A, thereby moving the magnetic head 28 along the width direction of the magnetic tape MT.

[0086] The tape drive 14 is provided with a tilt mechanism 49. The tilt mechanism 49 has a tilt actuator 49A. As the tilt actuator 49A, for example, a voice coil motor and / or a piezoelectric actuator can be cited. The tilt actuator 49A is connected to the control device 30, and the control device 30 controls the tilt actuator 49A. The tilt actuator 49A generates power under the control of the control device 30. The tilt mechanism 49 receives the power generated by the tilt actuator 49A, thereby tilting the magnetic head 28 toward the long side direction LD of the magnetic tape MT relative to the width direction WD of the magnetic tape MT (refer to FIG. 1 ). Figure 8 ). That is, the magnetic head 28 is deflected on the magnetic tape MT under the control of the control device 30.

[0087] Here, as a comparative example with respect to the magnetic tape MT, reference is made to Figure 6 to Figure 8 The case where the conventionally known magnetic tape MT0 is used in place of the magnetic tape MT is described. In addition, if the magnetic tape MT0 is compared with the magnetic tape MT, the difference is that the servo pattern 52 (reference Figure 6 ), in contrast, the servo pattern 58 (reference Fig. 9 ).

[0088] As an example, Figure 6 As shown, servo bands SB1, SB2 and SB3 and data bands DB1 and DB2 are formed on the surface 31 of the magnetic tape MT0. In addition, for the convenience of explanation, when there is no need to distinguish them, the servo bands SB1 to SB3 are referred to as servo bands SB, and the data bands DB1 and DB2 are referred to as data bands DB.

[0089] The servo bands SB1 to SB3 and the data bands DB1 and DB2 are formed along the long side direction LD (i.e., the full length direction) of the magnetic tape MT0. Here, in other words, the long side direction LD refers to the running direction of the magnetic tape MT0. The running direction of the magnetic tape MT0 is defined by two directions: the forward direction (hereinafter, also referred to as the "forward direction") in which the magnetic tape MT0 runs from the side of the delivery reel 22 to the side of the winding reel 38 and the reverse direction (hereinafter, also referred to as the "reverse direction") in which the magnetic tape MT0 runs from the side of the winding reel 38 to the side of the delivery reel 22.

[0090] The servo bands SB1 to SB3 are arranged at positions separated in the width direction WD (hereinafter, also referred to as "width direction WD") of the magnetic tape MT0. For example, the servo bands SB1 to SB3 are formed at equal intervals along the width direction WD. Here, the equal interval is an example of the "predetermined pitch" involved in the technology of the present invention. In addition, in this embodiment, "equal interval" refers to equal intervals in the sense of including errors that are generally allowed in the technical field to which the technology of the present invention belongs and do not deviate from the technical purpose of the present invention, in addition to completely equal intervals.

[0091] The data band DB1 is arranged between the servo band SB1 and the servo band SB2, and the data band DB2 is arranged between the servo band SB2 and the servo band SB3. That is, the servo bands SB and the data bands DB are alternately arranged along the width direction WD.

[0092] In addition, Figure 6 In the example shown, for the sake of convenience, three servo bands SB and two data bands DB are shown, but this is just an example. It can also be two servo bands SB and one data band DB. Even if there are more than four servo bands SB and more than three data bands DB, the technology of the present invention will also be applicable.

[0093] In the servo band SB, a plurality of servo patterns 52 are recorded along the long side direction LD of the magnetic tape MT0. The servo patterns 52 are classified into a servo pattern 52A and a servo pattern 52B. The plurality of servo patterns 52 are arranged at constant intervals along the long side direction LD of the magnetic tape MT0. In addition, in the present embodiment, "constant" means not only completely constant, but also constant in the sense of including errors that are generally allowed in the technical field to which the technology of the present invention belongs and do not deviate from the technical purpose of the present invention.

[0094] The servo band SB is divided into a plurality of frames 50 along the long side direction LD of the magnetic tape MT0. The frame 50 is defined by a set of servo patterns 52. Figure 6 In the example shown, servo patterns 52A and 52B are shown as an example of a set of servo patterns 52. Servo patterns 52A and 52B are adjacent to each other along the longitudinal direction LD of magnetic tape MT0. In frame 50, servo pattern 52A is located on the upstream side in the positive direction, and servo pattern 52B is located on the downstream side in the positive direction.

[0095] The servo pattern 52 is composed of linear magnetized region pairs 54. The linear magnetized region pairs 54 are classified into linear magnetized region pairs 54A and linear magnetized region pairs 54B.

[0096] The servo pattern 52A is composed of a pair of linear magnetized regions 54A. Figure 6 In the example shown, linear magnetized regions 54A1 and 54A2 are shown as an example of the linear magnetized region pair 54A. The linear magnetized regions 54A1 and 54A2 are regions magnetized linearly.

[0097] The linear magnetized regions 54A1 and 54A2 are inclined in opposite directions with respect to an imaginary straight line C1 which is an imaginary straight line along the width direction WD. Figure 6 In the example shown, the linear magnetized regions 54A1 and 54A2 are inclined in line symmetry with respect to the imaginary straight line C1. More specifically, the linear magnetized regions 54A1 and 54A2 are not parallel to each other, and are formed to be inclined at a predetermined angle (for example, 5 degrees) in the opposite direction of the long side direction LD of the magnetic tape MT0 with the imaginary straight line C1 as the axis of symmetry. In the present embodiment, the imaginary straight line C1 is an example of the "first imaginary straight line" and the "second imaginary straight line" involved in the technology of the present invention.

[0098] The linear magnetized region 54A1 is a set of five magnetized straight lines, namely, magnetized straight lines 54A1a. The linear magnetized region 54A2 is a set of five magnetized straight lines, namely, magnetized straight lines 54A2a.

[0099] The servo pattern 52B is composed of a pair of linear magnetized regions 54B. Figure 6In the example shown, linear magnetized regions 54B1 and 54B2 are shown as an example of the linear magnetized region pair 54B. The linear magnetized regions 54B1 and 54B2 are regions magnetized linearly.

[0100] The linear magnetized regions 54B1 and 54B2 are inclined in opposite directions with respect to an imaginary straight line C2 which is an imaginary straight line along the width direction WD. Figure 6 In the example shown, the linear magnetized regions 54B1 and 54B2 are inclined in line symmetry with respect to the imaginary straight line C2. More specifically, the linear magnetized regions 54B1 and 54B2 are not parallel to each other, and are formed to be inclined at a predetermined angle (for example, 5 degrees) in the opposite direction of the long side direction LD of the magnetic tape MT0 with the imaginary straight line C2 as the axis of symmetry. In the present embodiment, the imaginary straight line C2 is an example of the "first imaginary straight line" involved in the technology of the present invention.

[0101] The linear magnetized region 54B1 is a set of four magnetized straight lines, namely, magnetized straight lines 54B1a. The linear magnetized region 54B2 is a set of four magnetized straight lines, namely, magnetized straight lines 54B2a.

[0102] The magnetic head 28 is located on the surface 31 side of the magnetic tape MT0 thus constructed. The bracket 44 is formed in a rectangular parallelepiped shape and is configured to cross the surface 31 of the magnetic tape MT0 along the width direction WD. The multiple magnetic elements of the magnetic element unit 42 are arranged in a straight line along the long side direction of the bracket 44. The magnetic element unit 42 has a pair of servo reading elements SR and a plurality of data reading and writing elements DRW as multiple magnetic elements. The length of the bracket 44 in the long side direction is long enough relative to the width of the magnetic tape MT0. For example, the length of the bracket 44 in the long side direction is set to a length that exceeds the width of the magnetic tape MT0 at any position where the magnetic element unit 42 is configured on the magnetic tape MT0.

[0103] A pair of servo read elements SR is composed of servo read elements SR1 and SR2. The servo read element SR1 is arranged at one end of the magnetic element unit 42, and the servo read element SR2 is arranged at the other end of the magnetic element unit 42. Figure 6 In the example shown, the servo read element SR1 is disposed at a position corresponding to the servo band SB2 , and the servo read element SR2 is disposed at a position corresponding to the servo band SB3 .

[0104] The plurality of data read / write elements DRW are arranged in a straight line between the servo read element SR1 and the servo read element SR2. The plurality of data read / write elements DRW are arranged at intervals along the long side direction of the magnetic head 28 (for example, arranged at equal intervals along the long side direction of the magnetic head 28). Figure 6 In the example shown, a plurality of data read / write elements DRW are provided at positions corresponding to the data band DB2.

[0105] The control device 30 obtains a servo signal, which is a result of reading the servo pattern 52 by the servo reading element SR, and performs servo control according to the obtained servo signal. Here, servo control refers to control for moving the magnetic head 28 along the width direction WD of the magnetic tape MT0 by operating the moving mechanism 48 according to the servo pattern 52 read by the servo reading element SR.

[0106] By performing servo control, a plurality of data read / write elements DRW are located on a designated area within the data band DB, and magnetic processing is performed on the designated area within the data band DB. Figure 6 In the example shown, a designated area within the data band DB2 is magnetically processed by a plurality of data read / write elements DRW.

[0107] Furthermore, when the data band DB to be read by the magnetic element unit 42 is changed (in Figure 6 In the example shown, when the data band DB, which is the object of reading data by the magnetic element unit 42, is changed from the data band DB2 to the DB1, the moving mechanism 48, under the control of the control device 30, moves the magnetic head 28 along the width direction WD, thereby changing the position of a pair of servo reading elements SR. That is, the moving mechanism 48 moves the servo reading element SR1 to a position corresponding to the servo band SB1 and moves the servo reading element SR2 to a position corresponding to the servo band SB2 by moving the magnetic head 28 along the width direction WD. As a result, the positions of the plurality of data read / write elements DRW are changed from the data band DB2 to the data band DB1, and the data band DB1 is magnetically processed by the plurality of data read / write elements DRW.

[0108] In recent years, research related to technology to reduce the influence of TDS has been promoted. It is known that TDS depends on temperature, humidity, pressure of the magnetic tape wound on the reel, and deterioration over time. If no measures are taken, TDS becomes larger and off-track (i.e., the position of the data read / write element DRW relative to the track in the data tape DB) will occur when the data tape DB is magnetically processed.

[0109] exist Figure 7In the example shown, the manner in which the width of the magnetic tape MT0 shrinks over time is shown. In this case, a deviation from the track occurs. The width of the magnetic tape MT0 sometimes widens, in which case a deviation from the track also occurs. That is, if the width of the magnetic tape MT0 narrows or widens over time, the position of the servo read element SR relative to the servo pattern 52 will deviate from the predetermined position determined by the design (for example, the center position of each of the linear magnetized regions 54A1, 54A2, 54B1 and 54B2) in the width direction WD. If the position of the servo read element SR relative to the servo pattern 52 deviates from the predetermined position determined by the design in the width direction WD, the accuracy of the servo control is reduced, which causes the position of the magnetic track in the data band DB and the data read / write element DRW to deviate. In this way, the magnetic processing cannot be performed on the originally predetermined magnetic track.

[0110] As a method of reducing the influence of TDS, for example Figure 8 As shown, there is known a method of maintaining the position of the servo read element SR relative to the servo pattern 52 at a predetermined position determined by design by tilting the magnetic head 28 on the magnetic tape MT0.

[0111] The magnetic head 28 has a rotation axis RA. The rotation axis RA is set at a position corresponding to the center of the magnetic element unit 42 included in the magnetic head 28 when viewed from above. The magnetic head 28 is rotatably held on the tilt mechanism 49 via the rotation axis RA. An imaginary center line, i.e., an imaginary straight line C3, is set in the magnetic head 28. The imaginary straight line C3 is a straight line that passes through the rotation axis RA and extends along the long side direction of the magnetic head 28 when viewed from above (i.e., the direction in which multiple data read and write elements DRW are arranged). The magnetic head 28 is held by the tilt mechanism 49 in a posture in which the imaginary straight line C3 is tilted toward the long side direction LD of the magnetic tape MT0 relative to the imaginary straight line C4 along the width direction WD. Figure 8 In the example shown, the magnetic head 28 is in a posture in which the imaginary straight line C3 is tilted toward the delivery reel 22 relative to the imaginary straight line C4 (that is, in a posture in which the imaginary straight line C3 is tilted toward the delivery reel 22). Figure 8 The tilting mechanism 49 maintains the tilting posture (the posture tilted counterclockwise when viewed from the paper surface side).

[0112] The tilt mechanism 49 receives a tilt actuator 49A (refer to Figure 5 ) is used to rotate the magnetic head 28 on the surface 31 of the magnetic tape MT0 around the rotation axis RA. Under the control of the control device 30, the tilt mechanism 49 rotates the magnetic head 28 on the surface 31 of the magnetic tape MT0 around the rotation axis RA, thereby changing the direction and angle of the tilt (i.e., azimuth) of the imaginary straight line C3 relative to the imaginary straight line C4.

[0113] The inclination direction and angle of the imaginary straight line C3 relative to the imaginary straight line C4 change depending on the temperature, humidity, pressure of the magnetic tape MT0 wound on the reel, degradation over time, etc., or the expansion and contraction in the width direction WD of the magnetic tape MT caused by them, thereby maintaining the position of the servo reading element SR relative to the servo pattern 52 at a predetermined position determined by the design.

[0114] The servo read element SR is formed in a straight line along the imaginary straight line C3. Therefore, when the servo pattern 52A is read by the servo read element SR, in the linear magnetized region pair 54A, the angle formed by the linear magnetized region 54A1 and the servo read element SR is different from the angle formed by the linear magnetized region 54A2 and the servo read element SR. In this way, if the angles are different, a deviation (for example, a deviation in the signal level and a deformation of the waveform, etc.) caused by azimuth loss occurs between the servo signal originating from the linear magnetized region 54A1 (i.e., a servo signal obtained by reading the linear magnetized region 54A1 by the servo read element SR) and the servo signal originating from the linear magnetized region 54A2 (i.e., a servo signal obtained by reading the linear magnetized region 54A2 by the servo read element SR). Figure 8 In the example shown, the angle formed by the servo read element SR and the linear magnetized area 54A1 is larger than the angle formed by the servo read element SR and the linear magnetized area 54A2, so the output of the servo signal is small and the waveform is also widened, so that a deviation occurs in the servo signal read by the servo read element SR crossing the servo band SB in a state where the magnetic tape MT0 is traveling. In addition, when the servo pattern 52B is read by the servo read element SR, a deviation due to azimuth loss also occurs between the servo signal from the linear magnetized area 54B1 and the servo signal from the linear magnetized area 54B2. This deviation of the servo signal may become a cause of reducing the accuracy of servo control.

[0115] Furthermore, for example, as another example of the servo pattern 52A known in the past, consider a method in which the linear magnetized region 54A1 is parallel to the imaginary straight line C1, and the linear magnetized region 54A2 is inclined relative to the imaginary straight line C1 (i.e., a method in which only the linear magnetized region 54A2 is inclined). In this known method, when the servo pattern 52A is read by the servo read element SR, the angle formed by the linear magnetized region 54A1 and the servo read element SR and the angle formed by the linear magnetized region 54A2 and the servo read element SR in the linear magnetized region pair 54A are different. In this way, if the angles are different, a deviation due to azimuth loss occurs between the servo signal from the linear magnetized region 54A1 and the servo signal from the linear magnetized region 54A2. This deviation in the servo signal may become a cause of reducing the accuracy of servo control.

[0116] Therefore, in view of this situation, in this embodiment, as an example, Fig. 9 As shown, a magnetic tape MT is used. The magnetic tape MT is different from the magnetic tape MT0 in that it has a frame 56 instead of the frame 50. The frame 56 is defined by a set of servo patterns 58. In the following, the same reference numerals are given to the same components of the magnetic tape MT as those of the magnetic tape MT0, and the description thereof is omitted.

[0117] The servo band SB is formed by recording a plurality of servo patterns 58 along the long side direction LD in a band-shaped area 61 formed in a band shape along the long side direction LD on the magnetic tape MT. Similar to the plurality of servo patterns 52 recorded on the magnetic tape MT0, the plurality of servo patterns 58 are arranged at a constant interval along the long side direction LD of the magnetic tape MT. In the present embodiment, the band-shaped area 61 is an example of a "band-shaped area" involved in the technology of the present invention.

[0118] Each one end in the width direction WD of the plurality of servo patterns 58 is aligned in the width direction WD, and each other end in the width direction WD of the plurality of servo patterns 58 is also aligned in the width direction WD. The length of the width SWD of the servo band SB is specified by the length in the width direction WD of the plurality of servo patterns 58 recorded along the long side direction LD. That is, each one end in the width direction WD of the plurality of servo patterns 58 recorded along the long side direction LD specifies one end E1 of the width SWD of the servo band SB, and each other end in the width direction WD of the plurality of servo patterns 58 recorded along the long side direction LD specifies the other end E2 of the width SWD of the servo band SB.

[0119] exist Fig. 9 In the example shown, servo patterns 58A and 58B are shown as an example of a set of servo patterns 58 included in the frame 56. The servo patterns 58A and 58B are adjacent to each other along the long side direction LD of the magnetic tape MT, and the servo pattern 58A is located on the upstream side in the positive direction, and the servo pattern 58B is located on the downstream side in the positive direction in the frame 56. That is, on the servo band SB, the servo pattern 58A and the servo pattern 58B are alternately arranged along the long side direction LD.

[0120] The servo pattern 58 is composed of linear magnetized region pairs 60. The linear magnetized region pairs 60 are classified into linear magnetized region pairs 60A and linear magnetized region pairs 60B. In the present embodiment, the linear magnetized region pairs 60 are an example of “linear magnetized region pairs” involved in the technology of the present invention.

[0121] The servo pattern 58A is composed of a pair of linear magnetized regions 60A. Fig. 9 In the example shown, linear magnetized regions 60A1 and 60A2 are shown as an example of the linear magnetized region pair 60A. The linear magnetized regions 60A1 and 60A2 are regions magnetized linearly.

[0122] In the present embodiment, the linear magnetized region 60A1 is an example of the “first linear magnetized region” involved in the technology of the present invention, and the linear magnetized region 60A2 is an example of the “second linear magnetized region” involved in the technology of the present invention.

[0123] The linear magnetized regions 60A1 and 60A2 are inclined in opposite directions relative to the imaginary straight line C1. In other words, the linear magnetized region 60A1 is inclined in one direction (for example, from Fig. 9 On the other hand, the linear magnetized region 60A2 is inclined in another direction (for example, from the imaginary straight line C1) relative to the imaginary straight line C1. Fig. 9 The surface of the paper is tilted counterclockwise when viewed from the paper surface side.

[0124] The linear magnetized regions 60A1 and 60A2 are not parallel to each other and are inclined at different angles relative to the imaginary straight line C1. The inclination angle of the linear magnetized region 60A1 relative to the imaginary straight line C1 is steeper than that of the linear magnetized region 60A2. Here, "steep" means, for example, that the angle of the linear magnetized region 60A1 relative to the imaginary straight line C1 is smaller than the angle of the linear magnetized region 60A2 relative to the imaginary straight line C1. In addition, the total length of the linear magnetized region 60A1 is shorter than the total length of the linear magnetized region 60A2.

[0125] In the servo pattern 58A, the linear magnetized region 60A1 is a set of a plurality of magnetized straight lines 60A1a, and the linear magnetized region 60A2 is a set of a plurality of magnetized straight lines 60A2a. Here, the magnetized straight line 60A1a is an example of the "first magnetized straight line" involved in the technology of the present invention, and the magnetized straight line 60A2a is an example of the "second magnetized straight line" involved in the technology of the present invention.

[0126] The number of magnetized straight lines 60A1a included in the linear magnetized region 60A1 is the same as the number of magnetized straight lines 60A2a included in the linear magnetized region 60A2. The linear magnetized region 60A1 is a set of five magnetized straight lines, i.e., magnetized straight lines 60A1a, and the linear magnetized region 60A2 is a set of five magnetized straight lines, i.e., magnetized straight lines 60A2a.

[0127] In the servo band SB, in the width direction WD, the positions of both ends of the linear magnetized region 60A1 (i.e., the positions of both ends of the five magnetized straight lines 60A1a) and the positions of both ends of the linear magnetized region 60A2 (i.e., the positions of both ends of the five magnetized straight lines 60A2a) are aligned.

[0128] In addition, here, an example is given in which the positions of the two ends of each of the five magnetizing straight lines 60A1a are aligned with the positions of the two ends of each of the five magnetizing straight lines 60A2a, but this is just an example, and the positions of the two ends of at least one of the five magnetizing straight lines 60A1a are aligned with the positions of the two ends of at least one of the five magnetizing straight lines 60A2a.

[0129] Furthermore, in this embodiment, the concept of "alignment" includes not only the meaning of complete alignment, but also the meaning of "alignment" including errors that are generally allowed in the technical field to which the technology of the present invention belongs and that do not deviate from the technical spirit of the present invention.

[0130] The servo pattern 58B is composed of a pair of linear magnetized regions 60B. Fig. 9 In the illustrated example, linear magnetized regions 60B1 and 60B2 are illustrated as an example of the linear magnetized region pair 60B. The linear magnetized regions 60B1 and 60B2 are regions magnetized linearly.

[0131] In the present embodiment, the linear magnetized region 60B1 is an example of the “first linear magnetized region” involved in the technology of the present invention, and the linear magnetized region 60B2 is an example of the “second linear magnetized region” involved in the technology of the present invention.

[0132] The linear magnetized regions 60B1 and 60B2 are inclined in opposite directions relative to the imaginary straight line C2. In other words, the linear magnetized region 60B1 is inclined in one direction (for example, from Fig. 9 On the other hand, the linear magnetized region 60B2 is inclined in another direction (for example, from the imaginary straight line C2) relative to the imaginary straight line C2. Fig. 9 The surface of the paper is tilted counterclockwise when viewed from the paper surface side.

[0133] The linear magnetized regions 60B1 and 60B2 are not parallel to each other and are inclined at different angles relative to the imaginary straight line C2. The inclination angle of the linear magnetized region 60B1 relative to the imaginary straight line C2 is steeper than that of the linear magnetized region 60B2. Here, "steep" means, for example, that the angle of the linear magnetized region 60B1 relative to the imaginary straight line C2 is smaller than the angle of the linear magnetized region 60B2 relative to the imaginary straight line C2. In addition, the total length of the linear magnetized region 60B1 is shorter than the total length of the linear magnetized region 60B2.

[0134] In the servo pattern 58B, the linear magnetized region 60B1 is a set of a plurality of magnetized straight lines 60B1a, and the linear magnetized region 60B2 is a set of a plurality of magnetized straight lines 60B2a. Here, the magnetized straight line 60B1a is an example of the "first magnetized straight line" involved in the technology of the present invention, and the magnetized straight line 60B2a is an example of the "second magnetized straight line" involved in the technology of the present invention.

[0135] The number of magnetized straight lines 60B1a included in the linear magnetized region 60B1 is the same as the number of magnetized straight lines 60B2a included in the linear magnetized region 60B2. The linear magnetized region 60B1 is a set of four magnetized straight lines, i.e., magnetized straight lines 60B1a, and the linear magnetized region 60B2 is a set of four magnetized straight lines, i.e., magnetized straight lines 60B2a.

[0136] Thus, between the servo pattern 58A and the servo pattern 58B, the number of magnetizing straight lines 60A1a and the number of magnetizing straight lines 60B1a are different, and the number of magnetizing straight lines 60A2a and the number of magnetizing straight lines 60B2a are also different.

[0137] Furthermore, the total number of magnetization straight lines 60B1a and 60B2a included in the servo pattern 58B is also different from the total number of magnetization straight lines 60A1a and 60A2a included in the servo pattern 58A. Fig. 9 In the illustrated example, the total number of magnetization straight lines 60A1a and 60A2a included in the servo pattern 58A is ten, whereas the total number of magnetization straight lines 60B1a and 60B2a included in the servo pattern 58B is eight.

[0138] In the servo band SB, in the width direction WD, the positions of both ends of the linear magnetized region 60B1 (i.e., the positions of both ends of the four magnetized straight lines 60B1a) and the positions of both ends of the linear magnetized region 60B2 (i.e., the positions of both ends of the four magnetized straight lines 60B2a) are aligned.

[0139] In addition, here, an example is given in which the positions of the two ends of each of the four magnetizing straight lines 60B1a are aligned with the positions of the two ends of each of the four magnetizing straight lines 60B2a, but this is only an example, and the positions of the two ends of at least one of the four magnetizing straight lines 60B1a and the two ends of at least one of the four magnetizing straight lines 60B2a may be aligned.

[0140] Furthermore, here, as an example of the linear magnetized region 60A1, a set of five magnetized straight lines, namely, the magnetized straight lines 60A1a, is cited, as an example of the linear magnetized region 60A2, a set of five magnetized straight lines, namely, the magnetized straight lines 60A2a, as an example of the linear magnetized region 60B1, a set of four magnetized straight lines, namely, the magnetized straight lines 60B1a, and as an example of the linear magnetized region 60B2, a set of four magnetized straight lines, namely, the magnetized straight lines 60B2a, but the technology of the present invention is not limited to this. For example, the linear magnetized region 60A1 may be a magnetized straight line 60A1a that helps determine the number of positions of the magnetic head 28 on the magnetic tape MT, the linear magnetized region 60A2 may be a magnetized straight line 60A2a that helps determine the number of positions of the magnetic head 28 on the magnetic tape MT, the linear magnetized region 60B1 may be a magnetized straight line 60B1a that helps determine the number of positions of the magnetic head 28 on the magnetic tape MT, and the linear magnetized region 60B2 may be a magnetized straight line 60B2a that helps determine the number of positions of the magnetic head 28 on the magnetic tape MT.

[0141] Here, reference Fig.10 The geometrical characteristics of the linear magnetized region pair 60A on the magnetic tape MT will be described. In the present embodiment, the geometrical characteristics refer to generally recognized geometrical characteristics such as length, shape, orientation, and / or position.

[0142] As an example, Fig.10 As shown, the geometrical characteristics of the linear magnetized region pair 60A on the magnetic tape MT can be expressed using the imaginary linear region pair 62. The imaginary linear region pair 62 is composed of the imaginary linear region 62A and the imaginary linear region 62B. The geometrical characteristics of the linear magnetized region pair 60A on the magnetic tape MT are equivalent to the following geometrical characteristics: when the entire imaginary linear region pair 62 is tilted relative to the imaginary straight line C1 by tilting the symmetry axes SA1 of the imaginary linear regions 62A and the imaginary linear regions 62B that are tilted line-symmetrically relative to the imaginary straight line C1 relative to the imaginary straight line C1, the geometrical characteristics based on the imaginary linear region pair 62 are tilted relative to the imaginary straight line C1.

[0143] The imaginary linear region pair 62 is a pair having Figure 6 The imaginary linear magnetized region pair 62 is an imaginary magnetized region used for convenience in explaining the geometric characteristics of the linear magnetized region pair 60A on the magnetic tape MT, and is not an actual magnetized region.

[0144] The imaginary linear region 62A has Figure 6 The linear magnetized region 54A1 shown in FIG. Figure 6The five imaginary straight lines 62A1 corresponding to the five magnetization straight lines 54A1a shown in FIG. Figure 6 The linear magnetized region 54B1 shown in FIG. Figure 6 The five magnetization straight lines 54A2a shown are composed of five imaginary straight lines 62B1 corresponding to each other.

[0145] The center O1 is provided in the virtual linear region pair 62. For example, the center O1 is the center of a line segment L0 connecting the center of the straight line 62A1 located most upstream in the positive direction among the five straight lines 62A1 and the center of the straight line 62B1 located most downstream in the positive direction among the five straight lines 62B1.

[0146] The imaginary linear region pair 62 has Figure 6 Since the linear magnetized region pair 54A shown in FIG. 1 has the same geometric characteristics, the virtual linear region 62A and the virtual linear region 62B are inclined line-symmetrically with respect to the virtual straight line C1. Here, the following case is considered: when the virtual linear region pair 62 is tilted as a whole with respect to the virtual straight line C1 by tilting the symmetry axis SA1 of the virtual linear regions 62A and 62B with respect to the virtual straight line C1 at an angle a (for example, 10 degrees) with respect to the virtual straight line C1 with the center O1 as the rotation axis, if the virtual linear region pair 62 is read by the servo reading element SR. In this case, in the virtual linear region pair 62, in the width direction WD, there are portions where the virtual linear region 62A can be read but the virtual linear region 62B cannot be read, or where the virtual linear region 62A cannot be read but the virtual linear region 62B can be read. That is, when reading is performed by the servo reading element SR in each of the virtual linear regions 62A and 62B, insufficient portions and unnecessary portions are generated.

[0147] Therefore, by supplementing the insufficient parts and removing the unnecessary parts, the positions of the two ends of the imaginary linear area 62A (i.e., the positions of the two ends of each of the five straight lines 62A1) are aligned with the positions of the two ends of the imaginary linear area 62B (i.e., the positions of the two ends of each of the five straight lines 62B1) in the width direction WD.

[0148] The geometrical characteristics of the virtual linear region pair 62 thus obtained (i.e., the geometrical characteristics of the virtual servo pattern) are equivalent to the geometrical characteristics of the actual servo pattern 58A. That is, the linear magnetized region pair 60A having geometrical characteristics equivalent to the geometrical characteristics of the virtual linear region pair 62 obtained by aligning the positions of both ends of the virtual linear region 62A with the positions of both ends of the virtual linear region 62B in the width direction WD is recorded in the band-shaped region 61 (refer to Fig. 9 ).

[0149] The linear magnetized region pair 60B is different from the linear magnetized region pair 60A only in that it has four magnetized straight lines 60B1a instead of five magnetized straight lines 60A1a and four magnetized straight lines 60B2a instead of five magnetized straight lines 60A2a. Therefore, in the width direction WD, the linear magnetized region pair 60B having geometrical characteristics equivalent to those of an imaginary linear region pair (not shown) obtained by aligning the positions of the two ends of each of the four straight lines 62A1 with the positions of the two ends of each of the four straight lines 62B1 is recorded in the band-shaped region 61 (refer to FIG. 1 ). Fig. 9 ).

[0150] In this embodiment, if Fig.10 As shown, insufficient parts and unnecessary parts are generated by tilting the imaginary linear areas 62A and 62B at an angle a relative to the imaginary straight line C1 with the center O1 as the rotation axis, so the insufficient parts are supplemented and the unnecessary parts are removed. Here, in order to perform servo control, skew angle control and / or tension control with high precision, it is preferable to make the amount of the insufficient parts supplemented and the amount of the unnecessary parts removed consistent. In other words, it is preferable to eliminate the misalignment between one end side and the other end side in the width direction WD of the servo pattern 58 (for example, the imbalance between the amount of the insufficient parts supplemented and the amount of the unnecessary parts removed) and accurately determine the center position in the width direction WD of the servo band SB.

[0151] Therefore, in this embodiment, as an example, Fig.11 As shown, the length of the width SWD of the servo pattern SB is set according to the imaginary straight line C5, the position P1, the position P2, the position P3, the distance D1, the distance D2, the distance D3, and the distance D4.

[0152] Here, imaginary straight line C5 is an example of the "imaginary line" involved in the technology of the present invention. Position P1 is an example of the "first position" involved in the technology of the present invention. Position P2 is an example of the "second position" involved in the technology of the present invention. Position P3 is an example of the "third position" involved in the technology of the present invention. Distance D1 is an example of the "first distance" involved in the technology of the present invention. Distance D2 is an example of the "second distance" involved in the technology of the present invention. Distance D3 is an example of the "distance from the imaginary line to one end in the width direction of the servo band" involved in the technology of the present invention. Distance D4 is an example of the "distance from the imaginary line to the other end in the width direction of the servo band" involved in the technology of the present invention.

[0153] The imaginary straight line C5 is set with respect to the plurality of servo patterns 58 recorded along the longitudinal direction LD on the servo band SB. The imaginary straight line C5 crosses the plurality of servo patterns 58 along the longitudinal direction LD. The imaginary straight line C5 is not a straight line actually recorded on the servo band SB but an imaginary straight line for setting the width of the servo band SB.

[0154] The servo pattern 58A has a position P1 and a position P2. The position P1 is a position where the imaginary straight line C5 intersects the linear magnetized region 60A1. The position P2 is a position where the imaginary straight line C5 intersects the linear magnetized region 60A2.

[0155] exist Fig.11 In the example shown, one end (at the end of the longitudinal direction LD) of all magnetized straight lines 60A1a included in the linear magnetized region 60A1 is shown. Fig.11 In the example shown, the position where the magnetization straight line 60A1a (on the most upstream side in the traveling direction of the magnetic tape MT when the magnetic tape MT is traveling in the forward direction) intersects with the imaginary straight line C5 is defined as the position P1. Fig.11 In the example shown, one end (at the end of the longitudinal direction LD) of all magnetized straight lines 60A2a included in the linear magnetized region 60A2 is shown. Fig.11 In the example shown, the position where the magnetization straight line 60A2a (on the most upstream side in the traveling direction of the magnetic tape MT when the magnetic tape MT travels in the forward direction) intersects with the virtual straight line C5 is defined as the position P2.

[0156] The servo pattern 58B has a position P3. The position P3 is a position where the imaginary straight line C5 intersects the linear magnetized region 60B1.

[0157] exist Fig.11 In the example shown, one end (at the end of the longitudinal direction LD) of all magnetized straight lines 60B1a included in the linear magnetized region 60B1 is shown. Fig.11 In the example shown, the position where the magnetization straight line 60B1a on the upstream side (in the traveling direction of the magnetic tape MT) when the magnetic tape MT travels in the forward direction intersects the virtual straight line C5 is defined as the position P3.

[0158] The imaginary straight line C5 is set at a position where the distance D1 between the adjacent servo patterns 58A and 58B in the long side direction LD is half the distance D2 (for example, the ratio of the distance D1 to the distance D2 is "0.5"). The distance D1 refers to the distance between the position P1 and the position P2 in one servo pattern 58A. The distance D2 refers to the distance between the position P1 and the position P3 between the adjacent servo patterns 58A and 58B. In addition, in the present embodiment, "half" refers to half in the sense of including an error that is generally allowed in the technical field to which the technology of the present invention belongs and does not deviate from the technical spirit of the present invention (for example, a few %).

[0159] The width of the servo band SB is set to a length such that the distance D3 from the imaginary straight line C5 to one end E1 is consistent with the distance D4 from the imaginary straight line C5 to the other end E2. In addition, in this embodiment, "consistent" means not only completely consistent, but also consistent in the sense of including errors that are generally allowed in the technical field to which the technology of the present invention belongs and that do not deviate from the technical purpose of the present invention.

[0160] As an example, Fig.12 As shown, a plurality of servo bands SB are formed along the width direction WD in the magnetic tape MT, and the frames 56 corresponding to the servo bands SB are offset at predetermined intervals along the long side direction LD of the magnetic tape MT between the servo bands SB adjacent in the width direction WD. This means that the servo patterns 58 corresponding to the servo bands SB are offset at predetermined intervals along the long side direction LD of the magnetic tape MT between the servo bands SB adjacent in the width direction WD.

[0161] The predetermined interval is defined by the angle α, the pitch between adjacent servo bands SB in the width direction WD (hereinafter also referred to as “servo band pitch”), and the frame length. Fig.12 In the example shown, the angle α is exaggerated for easier visual understanding, but in reality, the angle α is, for example, about 15 degrees. The angle α is the angle between the frames 56 that are not in a corresponding relationship between the adjacent servo bands SB in the width direction WD and the imaginary straight line C1. Fig.12 In the example shown, as an example of the angle α, one frame 56 (in the pair of frames 56 corresponding to the servo bands SB adjacent to each other in the width direction WD) is shown. Fig.12 In the example shown, a frame 56 of the servo band SB3) is adjacent to another frame 56 of a pair of frames 56 (in Fig.12 In the example shown, the frame 56 of the servo band SB2 (a frame 56 corresponding to a frame 56 of the servo band SB3) is between the frames 56 ( Fig.12 In the example shown, the angle between the line segment L1) and the imaginary straight line C1. In this case, the frame length refers to the total length of the frame 56 in the long side direction LD of the magnetic tape MT. The predetermined interval is defined by the following formula (1). In addition, Mod (A / B) represents the remainder when "A" is divided by "B".

[0162] (Predetermined interval) = Mod {(Servo band pitch × tanα) / (Frame length)} ... (1)

[0163] In addition, Fig.12In the example shown, the angle α is exemplified as the angle between one frame 56 (hereinafter referred to as "first frame") of a pair of frames 56 in a corresponding relationship between adjacent servo bands SB in the width direction WD and the frame 56 adjacent to the other frame 56 (hereinafter referred to as "second frame") of the pair of frames 56 and the imaginary straight line C1, but the technology of the present invention is not limited to this. For example, the angle α may be the angle between the first frame and the frame 56 (hereinafter referred to as "third frame") separated from the second frame by two or more frames in the same servo band SB as the second frame, and the imaginary straight line C1. In this case, the "frame length" used in the formula (1) is the distance between the second frame and the third frame in the long side direction LD of the magnetic tape MT (for example, the distance from the front end of the second frame to the front end of the third frame).

[0164] As an example, Fig.13 As shown, when the servo pattern 58A (i.e., the linear magnetized region pair 60A) is read by the servo read element SR in a state where the direction of the imaginary straight line C1 coincides with the direction of the imaginary straight line C3 (i.e., the state where the long side direction of the magnetic head 28 coincides with the width direction WD), a deviation due to azimuth loss occurs between the servo signal from the linear magnetized region 60A1 and the servo signal from the linear magnetized region 60A2. Furthermore, when the servo pattern 58B (i.e., the linear magnetized region pair 60B) is read by the servo read element SR in a state where the direction of the imaginary straight line C1 coincides with the direction of the imaginary straight line C3 (i.e., the state where the long side direction of the magnetic head 28 coincides with the width direction WD), the same phenomenon occurs.

[0165] So, as an example, Fig.14 As shown, the tilt mechanism 49 (reference Figure 8 ) so that the imaginary straight line C3 is angled upstream relative to the imaginary straight line C1 at an angle β (i.e., from Fig.14 The magnetic head 28 is tilted on the magnetic tape MT with the rotation axis RA as the center in a manner that the magnetic head 28 is tilted at an angle β in the counterclockwise direction when viewed from the paper surface side. In this way, the magnetic head 28 is tilted at an angle β toward the upstream side in the positive direction on the magnetic tape MT, so that Fig.13 Compared with the example shown in FIG. 1 , the difference due to the azimuth loss between the servo signal from the linear magnetized region 60A1 and the servo signal from the linear magnetized region 60A2 is reduced. Also, when the servo pattern 58B (i.e., the linear magnetized region pair 60B) is read by the servo read element SR, the difference due to the azimuth loss between the servo signal from the linear magnetized region 60B1 and the servo signal from the linear magnetized region 60B2 is reduced.

[0166] Here, the angle β is set, for example, to be Fig.10) is the rotation axis so that the imaginary linear regions 62A and 62B (reference Fig.10 ) of the symmetry axis SA1 (reference Fig.10 ) is rotated relative to the imaginary straight line C1, that is, angle a (reference Fig.10 ). The geometrical characteristics of the imaginary linear regions 62A and 62B are the same as those of the linear magnetized regions 60A1 and 60B1. Therefore, the linear magnetized regions 60A1 and 60B1 are also inclined at an angle a relative to the imaginary straight line C1. In this case, if the magnetic head 28 is inclined at an angle β (i.e., angle a) toward the upstream side in the positive direction on the magnetic tape MT, the inclination angle β of the magnetic head 28 is consistent with the inclination angle a of the linear magnetized regions 60A1 and 60A2. As a result, the deviation caused by the azimuth loss between the servo signal derived from the linear magnetized region 60A1 and the servo signal derived from the linear magnetized region 60A2 is reduced. Moreover, when the servo pattern 58B (i.e., the linear magnetized region pair 60B) is read by the servo read element SR, similarly, the deviation caused by the azimuth loss between the servo signal derived from the linear magnetized region 60B1 and the servo signal derived from the linear magnetized region 60B2 is reduced.

[0167] As an example, Fig.15 As shown, the control device 30 includes a control unit 30A and a position detection unit 30B. The position detection unit 30B includes a first position detection unit 30B1 and a second position detection unit 30B2. The position detection unit 30B acquires a servo signal, which is a result of reading the servo pattern 58 by the servo reading element SR, and detects the position of the magnetic head 28 on the magnetic tape MT based on the acquired servo signal.

[0168] The servo signal is classified into a first servo signal and a second servo signal. The first servo signal is a servo signal obtained by reading the servo pattern 58 by the servo reading element SR1, and the second servo signal is a servo signal obtained by reading the servo pattern 58 by the servo reading element SR2.

[0169] The first position detection unit 30B1 acquires a first servo signal, and the second position detection unit 30B2 acquires a second servo signal. Fig.15 In the example shown, the first position detection unit 30B1 acquires a first servo signal obtained by reading the servo pattern 58 in the servo band SB2 by the servo read element SR1, and the second position detection unit 30B2 acquires a second servo signal obtained by reading the servo pattern 58 in the servo band SB3 by the servo read element SR2. The first position detection unit 30B1 detects the position of the servo read element SR1 relative to the servo band SB2 based on the first servo signal, and the second position detection unit 30B2 detects the position of the servo read element SR2 relative to the servo band SB3 based on the second servo signal.

[0170] The control unit 30A performs various controls based on the position detection result of the first position detection unit 30B1 (i.e., the result of the position detection by the first position detection unit 30B1) and the position detection result of the second position detection unit 30B2 (i.e., the result of the position detection by the second position detection unit 30B2). Here, the various controls refer to, for example, servo control, skew angle control, and / or tension control. Tension control refers to control of the tension applied to the magnetic tape MT (e.g., tension for reducing the influence of TDS).

[0171] As an example, Fig.16 As shown, the position detection unit 30B detects a servo signal which is a result of reading the servo pattern 58 from the magnetic tape MT by the servo read element SR using the autocorrelation coefficient.

[0172] The storage device 32 stores an ideal waveform signal 66. The ideal waveform signal 66 is a signal representing a single ideal waveform included in the servo signal (for example, an ideal signal obtained by reading one ideal magnetization straight line included in the servo pattern 58 by the servo reading element SR). The ideal waveform signal 66 can be said to be a sample signal to be compared with the servo signal. In addition, here, an example in which the ideal waveform signal 66 is stored in the storage device 32 is given, but this is only an example. For example, the ideal waveform signal 66 may be stored in the cassette memory 24 instead of the storage device 32, or may be stored in the storage device 32 and the cassette memory 24 at the same time. Furthermore, the ideal waveform signal 66 may be recorded in a BOT area (not shown) provided at the head of the magnetic tape MT and / or an EOT area (not shown) provided at the end of the magnetic tape MT.

[0173] The autocorrelation coefficient used by the position detection section 30B is a coefficient indicating the degree of correlation between the servo signal and the ideal waveform signal 66. The position detection section 30B acquires the ideal waveform signal 66 from the storage device 32, and compares the acquired ideal waveform signal 66 with the servo signal. Then, the position detection section 30B calculates the autocorrelation coefficient based on the comparison result. The position detection section 30B detects a position on the servo band SB where the correlation between the servo signal and the ideal waveform signal 66 is high (for example, a position where the servo signal and the ideal waveform signal 66 coincide with each other) according to the autocorrelation coefficient.

[0174] The position of the servo reading element SR relative to the servo band SB is detected, for example, based on the interval in the long-side direction LD of the servo patterns 58A and 58B. For example, the interval in the long-side direction LD of the servo patterns 58A and 58B is detected based on the autocorrelation coefficient. Fig.15When the servo pattern 58 is viewed from the front side of the paper (the upper side), the interval between the linear magnetized region 60A1 and the linear magnetized region 60A2 becomes narrower, and the interval between the linear magnetized region 60B1 and the linear magnetized region 60B2 also becomes narrower. In contrast, when the servo read element SR is located on the lower side of the servo pattern 58 (i.e., Fig.15 When the position detector 30B detects the position of the servo read element SR relative to the servo band SB, the interval between the linear magnetized region 60A1 and the linear magnetized region 60A2 becomes wider, and the interval between the linear magnetized region 60B1 and the linear magnetized region 60B2 also becomes wider. In this way, the position detector 30B detects the position of the servo read element SR relative to the servo band SB using the interval between the linear magnetized region 60A1 and the linear magnetized region 60A2 and the interval between the linear magnetized region 60B1 and the linear magnetized region 60B2 detected according to the autocorrelation coefficient.

[0175] The control unit 30A adjusts the position of the magnetic head 28 by operating the moving mechanism 48 according to the position detection result in the position detection unit 30B (i.e., the result of the position detection by the position detection unit 30B). In addition, the control unit 30A causes the magnetic element unit 42 to perform magnetic processing on the data band DB of the magnetic tape MT. That is, the control unit 30A obtains a read signal from the magnetic element unit 42 (i.e., data read from the data band DB of the magnetic tape MT by the magnetic element unit 42), or supplies a record signal to the magnetic element unit 42 to record data corresponding to the record signal on the data band DB of the magnetic tape MT.

[0176] Furthermore, in order to reduce the influence of TDS, the control unit 30A calculates the servo band pitch based on the position detection result in the position detection unit 30B, performs tension control according to the calculated servo band pitch, or deflects the magnetic head 28 on the magnetic tape MT. The tension control is achieved by adjusting the rotation speed and torque of the delivery motor 36 and the take-up motor 40, respectively. The deflection of the magnetic head 28 is achieved by operating the tilt mechanism 49.

[0177] Next, among the multiple steps included in the manufacturing process of the magnetic tape MT, the steps of performing ... Fig. 9 and Fig.11 ) records the servo pattern 58 to form a servo band SB (reference Fig. 9 and Fig.11 ) and an example of a servo pattern recording process and a winding process of winding up the magnetic tape MT are described.

[0178] As an example, Fig.17As shown, in the servo pattern recording process, a servo writer SW is used. The servo writer SW includes a feed reel SW1, a take-up reel SW2, a drive device SW3, a pulse signal generator SW4, a control device SW5, a plurality of guides SW6, a conveying path SW7, a servo pattern recording head WH, and a verification head VH.

[0179] In the present embodiment, the servo writer SW is an example of the "servo pattern recording device" and "inspection device" involved in the technology of the present invention. In addition, in the present embodiment, the pulse signal generator SW4 is an example of the "pulse signal generator" involved in the technology of the present invention. In addition, in the present embodiment, the servo pattern recording head WH is an example of the "servo pattern recording head" involved in the technology of the present invention. In addition, in the present embodiment, the control device SW5 is an example of the "inspection processor" involved in the technology of the present invention.

[0180] The control device SW5 controls the entire servo writer SW. In the present embodiment, the control device SW5 is implemented by an ASIC, but the technology of the present invention is not limited thereto. For example, the control device SW5 can be implemented by an FPGA and / or a PLC. Furthermore, the control device SW5 can also be implemented by a computer including a CPU, a flash memory (for example, an EEPROM and / or an SSD, etc.) and a RAM. Furthermore, it can also be implemented by a combination of two or more of an ASIC, an FPGA, a PLC and a computer. That is, the control device SW5 can also be implemented by a combination of a hardware structure and a software structure.

[0181] A reel is provided on the delivery reel SW1. The reel is a large-diameter reel in which the magnetic tape MT cut into a product width from a wide reel before writing the servo pattern 58 is wound around a hub.

[0182] The drive device SW3 has a motor (not shown) and a gear (not shown), and is mechanically connected to the feed reel SW1 and the take-up reel SW2. When the magnetic tape MT is taken up by the take-up reel SW2, the drive device SW3 generates power according to the instruction from the control device SW5, and transmits the generated power to the feed reel SW1 and the take-up reel SW2, thereby rotating the feed reel SW1 and the take-up reel SW2. That is, the feed reel SW1 receives power from the drive device SW3 and rotates, thereby feeding the magnetic tape MT to a predetermined conveying path SW7. The take-up reel SW2 receives power from the drive device SW3 and rotates, thereby taking up the magnetic tape MT fed from the feed reel SW1. The rotation speed and torque of the feed reel SW1 and the take-up reel SW2 are adjusted according to the speed at which the magnetic tape MT is taken up on the take-up reel SW2.

[0183] A plurality of guides SW6 and a servo pattern recording head WH are arranged on the transport path SW7. The servo pattern recording head WH is arranged between the plurality of guides SW6 on the surface 31 side of the magnetic tape MT. The magnetic tape MT fed from the feed reel SW1 to the transport path SW7 is guided by the plurality of guides SW6, passes over the servo pattern recording head WH, and is taken up by the take-up reel SW2.

[0184] The pulse signal generator SW4 generates a pulse signal under the control of the control device SW5, and supplies the generated pulse signal to the servo pattern recording head WH. When the magnetic tape MT travels on the transport path SW at a constant speed, the servo pattern recording head WH records the servo pattern 58 in the band-shaped area 61 according to the pulse signal supplied from the pulse signal generator SW4 to form a servo band SB.

[0185] The servo pattern recording process includes an inspection process. For example, the inspection process is a process of inspecting the servo band SB formed on the surface 31 of the magnetic tape MT by the servo pattern recording head WH. The inspection of the servo band SB includes, for example, a first determination process and a second determination process. The first determination process is to determine the width SWD (refer to Fig.11 The second determination process is to determine whether the servo pattern 58 recorded in the servo band SB is correct (for example, to determine whether the magnetization straight lines 60A1a, 60A2a, 60B1a, and 60B2a are recorded in the band region 61 (refer to FIG. 1 ) exactly and within the allowable error). Fig.11 ) processing (ie, verification of the servo pattern 58)).

[0186] The inspection process is performed by using the control device SW5 and the verification head VH. The verification head VH is arranged at a position closer to the downstream side of the conveying direction of the magnetic tape MT than the servo pattern recording head WH. Also, as with the magnetic head 28, a plurality of servo reading elements (not shown) are provided in the verification head VH, and a plurality of servo bands SB are read by the plurality of servo reading elements. Also, as with the magnetic head 28, the verification head VH is tilted on the surface 31 of the magnetic tape MT.

[0187] The verification head VH is connected to the control device SW5. The verification head VH is arranged at a position facing the servo band SB as viewed from the surface 31 side of the magnetic tape MT (i.e., the back side of the verification head VH), reads the servo pattern 58 recorded in the servo band SB, and outputs the read result (hereinafter referred to as "servo pattern reading result") to the control device SW5. The control device SW5 checks the servo band SB (e.g., determines whether the servo pattern 58 is correct) based on the servo pattern reading result (e.g., servo signal) input from the verification head VH. For example, the control device SW5 performs a check on the servo band SB as Fig.15The position detection unit 30B shown in the figure operates to obtain a position detection result from the servo pattern reading result, and checks the servo band SB by determining whether the servo pattern 58 is correct using the position detection result.

[0188] The control device SW5 controls the servo writer SW with reference to the result of checking the servo band SB (for example, the result of the first determination process and the result of the second determination process). For example, when the first determination process determines that the width SWD is not set within the allowable error (reference Fig.11 ), the control device SW5 controls the pulse signal generator SW4 and / or the driving device SW3 etc. according to the servo pattern reading result, thereby Fig.11 The width SWD is set to a length that is equal to the distance D3 and the distance D4 as shown in FIG. The reason for controlling the pulse signal generator SW4 and / or the drive device SW3 is that the gap pattern G (reference Fig.18 and Fig.19 ) to determine the equivalent of Fig.11 The length of distance D1 shown, therefore, in order to set distance D1 to half of distance D2, it is necessary to adjust Fig.11 The distance D2 is shown. In order to adjust Fig.11 In order to adjust the distance D2 shown, it is necessary to fine-tune the timing of generating the pulse signal or adjust the traveling speed of the magnetic tape MT, and thus the control device SW5 controls the pulse signal generator SW4 and / or the drive device SW3, etc. Furthermore, when it is determined by the second determination process that the servo pattern 58 recorded on the servo band SB is incorrect, the control device SW5 controls the pulse signal generator SW4 and / or the servo pattern recording head WH, etc., based on the servo pattern reading result, thereby recording the magnetization straight lines 60A1a, 60A2a, 60B1a, and 60B2a in the band-shaped area 61 (reference number 60A1a, reference number 60A2a, reference number 60B1a, and reference number 60B2a) exactly within the allowable error. Fig.11 ). In addition, the control device SW5 may output information indicating the result of checking the servo band SB to a predetermined output destination (for example, the storage device 32 (refer to Figure 3 )、UI system device 34 (reference Figure 3 ) and / or external device 37 (reference Figure 3 )wait).

[0189] For example, if the inspection process is completed, the winding process is then performed. The winding process is to respectively check the plurality of tape cassettes 12 (reference Figure 1 to Figure 4 ) used in the delivery reel 22 (ie, contained in the tape cassette 12 (reference Figure 1 to Figure 4 ) of the delivery reel 22 (reference Figure 2 to Figure 4)) is a process of winding up the magnetic tape MT. A winding motor M is used in the winding process. The winding motor M is mechanically connected to the delivery reel 22 via gears and the like. The winding motor M rotates the delivery reel 22 by applying a rotational force to the delivery reel 22 under the control of a control device (not shown in the figure). The magnetic tape MT wound on the winding reel SW2 is wound around the delivery reel 22 by the rotation of the delivery reel 22. A cutting device (not shown in the figure) is used in the winding process. If the required amount of magnetic tape MT is wound up by the delivery reel 22 on each of the plurality of delivery reels 22, the magnetic tape MT delivered from the winding reel SW2 to the delivery reel 22 is cut by the cutting device.

[0190] exist Fig.18 The figure shows the transmission path SW7 (reference Fig.17 ) when observing the servo pattern recording head WH from the surface 31 side of the magnetic tape MT traveling on the magnetic tape (i.e., the back side of the servo pattern recording head WH) and an example of the structure of the pulse signal generator SW4.

[0191] As an example, Fig.18 As shown, the servo pattern recording head WH has a base WH1 and a plurality of magnetic head cores WH2. The base WH1 is formed in a rectangular parallelepiped shape and is arranged to cross the surface 31 of the magnetic tape MT traveling on the transport path SW7 along the width direction WD. The surface WH1A of the base WH1 is a rectangle having a long side WH1Aa and a short side WH1Ab, and the long side WH1Aa crosses the surface 31 of the magnetic tape MT along the width direction WD.

[0192] The surface WH1A has a sliding surface WH1Ax. The sliding surface WH1Ax is a surface (for example, Fig.18 The dotted hatched area shown in the figure) and slides relative to the magnetic tape MT in the traveling state. Fig.18 The width of the sliding surface WH1Ax shown (i.e., the length in the direction LD1 corresponding to the long side direction LD (e.g., the same direction as the long side direction LD)) is only an example, and the width of the sliding surface WH1Ax may be several times wider than Fig.18 Example shown.

[0193] The long side direction of the substrate WH1, i.e., direction WD1 (i.e., the direction along the long side WH1Aa), is a direction corresponding to the width direction WD (e.g., the same direction as the width direction WD). A plurality of magnetic head cores WH2 are assembled along the direction WD1 in the substrate WH1. A gap pattern G is formed in the magnetic head core WH2. The gap pattern G is formed on the surface WH1A (i.e., the surface on the side of the substrate WH1 that is opposite to the surface 31 of the magnetic tape MT). Furthermore, the gap pattern G is composed of a pair of non-parallel straight line regions. For example, a pair of non-parallel straight line regions refers to Fig. 9 The linear region of the five magnetizing straight lines 60A1a included in the linear magnetizing region 60A1 shown has the same geometrical characteristics as the magnetizing straight line 60A1a located on the upstream side in the positive direction and the linear region of the magnetizing straight line 60A1a. Fig. 9 The illustrated linear magnetization region 60A2 is a linear region having the same geometrical characteristics as the magnetization straight line 60A2a located on the upstream side in the positive direction among the five magnetization straight lines 60A2a included in the linear magnetization region 60A2.

[0194] A plurality of gap patterns G are formed along the direction WD1 on the surface WH1A. On the surface WH1A, the interval in the direction WD1 between gap patterns G adjacent to each other in the direction WD1 corresponds to the interval in the width direction WD between band regions 61 of the magnetic tape MT (ie, the servo band pitch).

[0195] A coil (not shown) is wound around the head core WH2, and a pulse signal is supplied to the coil. The pulse signal supplied to the coil is a pulse signal for the servo pattern 58A and a pulse signal for the servo pattern 58B.

[0196] When a pulse signal for the servo pattern 58A is supplied to the coil of the head core WH2 in a state where the gap pattern G is directly opposite to the band-shaped area 61 of the magnetic tape MT traveling on the transport path SW7, a magnetic field is imparted to the band-shaped area 61 of the magnetic tape MT from the gap pattern G in accordance with the pulse signal. Thus, the servo pattern 58A is recorded on the band-shaped area 61. When a pulse signal for the servo pattern 58B is supplied to the coil of the head core WH2 in a state where the gap pattern G is directly opposite to the band-shaped area 61 of the magnetic tape MT traveling on the transport path SW7, a magnetic field is imparted to the band-shaped area 61 of the magnetic tape MT from the gap pattern G. In this way, a servo band SB is formed by recording the servo pattern 58B in the band-shaped area 61 (refer to Fig. 9 and Fig.11 ).

[0197] Each servo pattern 58 (ie, each frame 56 (reference Fig. 9) is modulated by a pulse signal corresponding to the servo pattern 58). By modulating the pulse signal, various information is embedded in the pulse signal. In this case, for example, by modulating the servo pattern 58A with a pulse signal, five magnetization straight lines 60A1a (reference Fig. 9 ) and the interval between the third magnetization straight line 60A1a and the second magnetization straight line 60A1a (hereinafter referred to as the "first interval") and the interval between the third magnetization straight line 60A1a and the fourth magnetization straight line 60A1a (hereinafter referred to as the "second interval"). By making the first interval and the second interval different for each servo pattern 58A, at least one bit of information can be embedded in each servo pattern 58A. Thus, various information can be embedded by combining a plurality of servo patterns 58A.

[0198] The various types of information include, for example, information regarding the position of the magnetic tape MT in the longitudinal direction LD, information for identifying the servo band SB, and / or information for specifying the manufacturer of the magnetic tape MT.

[0199] exist Fig.18 In the example shown, as an example of a plurality of head cores WH2, head cores WH2A, WH2B, and WH2C are shown, and as an example of a plurality of gap patterns G, gap patterns G1, G2, and G3 are shown. Gap pattern G1 is formed in head core WH2A. Gap pattern G2 is formed in head core WH2B. Gap pattern G3 is formed in head core WH2C.

[0200] The gap patterns G1 to G3 have the same geometric characteristics. In this embodiment, for example, the gap pattern G1 is used to adjust the servo band SB3 (refer to Fig. 9 ) of the servo pattern 58 (reference Fig. 9 ) is recorded, the gap pattern G2 is used for the servo band SB2 (reference Fig. 9 ) of the servo pattern 58 (reference Fig. 9 ) is recorded, the gap pattern G3 is used for the servo band SB1 (reference Fig. 9 ) of the servo pattern 58 (reference Fig. 9 ) records.

[0201] The gap pattern G1 is a pair of straight line regions composed of straight line regions G1A and G1B. The gap pattern G2 is a pair of straight line regions composed of straight line regions G2A and G2B. The gap pattern G3 is a pair of straight line regions composed of straight line regions G3A and G3B.

[0202] In the present embodiment, the straight line region pair composed of the straight line regions G1A and G1B, the straight line region pair composed of the straight line regions G2A and G2B, and the straight line region pair composed of the straight line regions G3A and G3B are examples of the "straight line region pair" involved in the technology of the present invention. In addition, in the present embodiment, the straight line regions G1A, G2A, and G3A are examples of the "first straight line region" involved in the technology of the present invention. In addition, in the present embodiment, the straight line regions G1B, G2B, and G3B are examples of the "second straight line region" involved in the technology of the present invention.

[0203] The pulse signal generator SW4 includes a first pulse signal generator SW4A, a second pulse signal generator SW4B, and a third pulse signal generator SW4C. The first pulse signal generator SW4A is connected to the magnetic head core WH2A. The second pulse signal generator SW4B is connected to the magnetic head core WH2B. The third pulse signal generator SW4C is connected to the magnetic head core WH2C.

[0204] In the band area 61 (reference Fig. 9 ) When the gap pattern G1 is used, if the first pulse signal generator SW4A supplies a pulse signal to the head core WH2A, a magnetic field is applied to the band-shaped area 61 corresponding to the servo band SB3 from the gap pattern G1 according to the pulse signal, and the servo pattern 58 is recorded on the band-shaped area 61 corresponding to the servo band SB3 (refer to Fig. 9 ). Thus, a servo band SB3 is formed on the magnetic tape MT.

[0205] For example, when a pulse signal for the servo pattern 58A is supplied to the head core WH2A while the gap pattern G1 is facing the band-shaped area 61 corresponding to the servo band SB3 of the magnetic tape MT traveling on the transport path SW7, the servo pattern 58A is recorded in the band-shaped area 61 corresponding to the servo band SB3 (see FIG. Fig. 9 That is, the linear magnetized region 60A1 is recorded in the band region 61 corresponding to the servo band SB3 through the linear region G1A (refer to Fig. 9 ), and the linear magnetized region 60A2 is recorded in the band region 61 corresponding to the servo band SB3 through the linear region G1B (reference Fig. 9 ).

[0206] Furthermore, for example, when a pulse signal for the servo pattern 58B is supplied to the head core WH2A in a state where the gap pattern G1 faces the band-shaped area 61 corresponding to the servo band SB3 of the magnetic tape MT traveling on the transport path SW7, the servo pattern 58B is recorded in the band-shaped area 61 corresponding to the servo band SB3 (see Fig. 9That is, the linear magnetized region 60B1 is recorded in the band region 61 corresponding to the servo band SB3 through the linear region G1A (refer to Fig. 9 ), and the linear magnetized region 60B2 is recorded in the band region 61 corresponding to the servo band SB3 through the linear region G1B (reference Fig. 9 ).

[0207] In this manner, the servo pattern 58A and the servo pattern 58B are recorded alternately in the band-shaped area 61 corresponding to the servo band SB3, so that the servo band SB3 is formed on the magnetic tape MT.

[0208] In the band area 61 (reference Fig. 9 ) When the gap pattern G2 is used, if the second pulse signal generator SW4B supplies a pulse signal to the head core WH2B, a magnetic field is applied to the band-shaped area 61 corresponding to the servo band SB2 from the gap pattern G2 according to the pulse signal, and the servo pattern 58 is recorded in the band-shaped area 61 corresponding to the servo band SB2. Thus, the servo band SB2 is formed on the magnetic tape MT.

[0209] For example, when a pulse signal for the servo pattern 58A is supplied to the head core WH2B in a state where the gap pattern G2 faces the band-shaped area 61 corresponding to the servo band SB2 of the magnetic tape MT traveling on the transport path SW7, the servo pattern 58A is recorded in the band-shaped area 61 corresponding to the servo band SB2 (see Fig. 9 That is, the linear magnetized region 60A1 is recorded in the band-shaped region 61 corresponding to the servo band SB2 through the linear region G2A, and the linear magnetized region 60A2 is recorded in the band-shaped region 61 corresponding to the servo band SB2 through the linear region G2B.

[0210] Furthermore, for example, when a pulse signal for the servo pattern 58B is supplied to the head core WH2B in a state where the gap pattern G2 faces the band-shaped area 61 corresponding to the servo band SB2 of the magnetic tape MT traveling on the transport path SW7, the servo pattern 58B is recorded on the band-shaped area 61 corresponding to the servo band SB2. That is, the linear magnetized area 60B1 is recorded on the band-shaped area 61 corresponding to the servo band SB2 by the straight line area G2A, and the linear magnetized area 60B2 is recorded on the band-shaped area 61 corresponding to the servo band SB2 by the straight line area G2B.

[0211] In this manner, the servo pattern 58A and the servo pattern 58B are recorded alternately in the band-shaped area 61 corresponding to the servo band SB2, so that the servo band SB2 is formed on the magnetic tape MT.

[0212] In the case of the band area 61 (reference Fig. 9) When the gap pattern G3 is used, if the third pulse signal generator SW4C supplies a pulse signal to the head core WH2C, a magnetic field is applied to the band-shaped area 61 corresponding to the servo band SB1 from the gap pattern G3 according to the pulse signal, and the servo pattern 58 is recorded in the band-shaped area 61 corresponding to the servo band SB1. Thus, the servo band SB1 is formed on the magnetic tape MT.

[0213] For example, when a pulse signal for the servo pattern 58A is supplied to the head core WH2C in a state where the gap pattern G3 faces the band-shaped area 61 corresponding to the servo band SB1 of the magnetic tape MT traveling on the transport path SW7, the servo pattern 58A is recorded on the band-shaped area 61 corresponding to the servo band SB1. That is, the linear magnetized area 60A1 is recorded on the band-shaped area 61 corresponding to the servo band SB1 by the straight area G3A, and the linear magnetized area 60A2 is recorded on the band-shaped area 61 corresponding to the servo band SB1 by the straight area G3B. Thus, the servo band SB1 is formed on the magnetic tape MT.

[0214] Furthermore, for example, when a pulse signal for the servo pattern 58B is supplied to the head core WH2C in a state where the gap pattern G3 faces the band-shaped area 61 corresponding to the servo band SB1 of the magnetic tape MT traveling on the transport path SW7, the servo pattern 58B is recorded on the band-shaped area 61 corresponding to the servo band SB1. That is, the linear magnetized area 60B1 is recorded on the band-shaped area 61 corresponding to the servo band SB1 by the straight area G3A, and the linear magnetized area 60B2 is recorded on the band-shaped area 61 corresponding to the servo band SB1 by the straight area G3B.

[0215] In this manner, the servo pattern 58A and the servo pattern 58B are recorded alternately in the band-shaped area 61 corresponding to the servo band SB1, so that the servo band SB1 is formed on the magnetic tape MT.

[0216] As an example, Fig.19 As shown in FIG. 1 , in the gap pattern G1, the straight line regions G1A and G1B are inclined in opposite directions relative to the imaginary straight line C1 which is a straight line along the direction WD1. In other words, the straight line region G1A is inclined in one direction (for example, from the imaginary straight line C1) relative to the imaginary straight line C1. Fig.19 On the other hand, the straight line region G1B is inclined in another direction (for example, from the imaginary straight line C1) relative to the imaginary straight line C1. Fig.19 The surface of the paper is tilted counterclockwise when viewed from the paper surface side.

[0217] Furthermore, the straight region G1A has a steeper inclination angle relative to the imaginary straight line C1 than the straight region G1B. Here, "steep" means, for example, that the angle of the straight region G1A relative to the imaginary straight line C1 is smaller than the angle of the straight region G1B relative to the imaginary straight line C1. Furthermore, the positions of both ends of the straight region G1A and the positions of both ends of the straight region G1B are aligned in the direction WD1. Furthermore, the total length of the straight region G1A is shorter than the total length of the straight region G1B.

[0218] In the gap pattern G2, the straight line regions G2A and G2B are inclined in opposite directions relative to the imaginary straight line C1. In other words, the straight line region G2A is inclined in one direction (for example, from Fig.19 On the other hand, the straight line region G2B is inclined in another direction (for example, from the imaginary straight line C1) relative to the imaginary straight line C1. Fig.19 The surface of the paper is tilted counterclockwise when viewed from the paper surface side.

[0219] Furthermore, the straight region G2A has a steeper inclination angle relative to the imaginary straight line C1 than the straight region G2B. Here, “steep” means, for example, that the angle of the straight region G2A relative to the imaginary straight line C1 is smaller than the angle of the straight region G2B relative to the imaginary straight line C1. Furthermore, the positions of both ends of the straight region G2A and the positions of both ends of the straight region G2B are aligned in the direction WD1. Furthermore, the total length of the straight region G2A is shorter than the total length of the straight region G2B.

[0220] In the gap pattern G3, the straight line regions G3A and G3B are inclined in opposite directions relative to the imaginary straight line C1. In other words, the straight line region G3A is inclined in one direction (for example, from Fig.19 On the other hand, the straight line region G3B is inclined in another direction (for example, from the imaginary straight line C1) relative to the imaginary straight line C1. Fig.19 The surface of the paper is tilted counterclockwise when viewed from the paper surface side.

[0221] Furthermore, the straight region G3A has a steeper inclination angle relative to the imaginary straight line C1 than the straight region G3B. Here, "steep" means, for example, that the angle of the straight region G3A relative to the imaginary straight line C1 is smaller than the angle of the straight region G3B relative to the imaginary straight line C1. Furthermore, the positions of both ends of the straight region G3A and the positions of both ends of the straight region G3B are aligned in the direction WD1. Furthermore, the total length of the straight region G3A is shorter than the total length of the straight region G3B.

[0222] The gap patterns G1 , G2 , and G3 are offset in the direction LD1 by the above-mentioned predetermined interval (that is, the predetermined interval calculated by the formula (1)) between the gap patterns G adjacent to each other along the direction WD1 .

[0223] On the surface WH1A, the long side WH1Aa is longer than the width of the magnetic tape MT. The short side WH1Ab is the length that accommodates all the gap patterns G1, G2, and G3. In other words, the length that accommodates all the gap patterns G1, G2, and G3 means the length from the straight area G1A to the straight area G3B along the long side direction LD of the magnetic tape MT. The direction of the long side WH1Aa coincides with the width direction WD, and the direction of the short side WH1Ab coincides with the long side direction LD of the magnetic tape MT. The base WH1 is arranged on the surface 31 side of the magnetic tape MT so that the plurality of gap patterns G are opposite to the surface 31 and cross the magnetic tape MT along the width direction WD.

[0224] The pulse signal used between the gap patterns G1, G2 and G3 (ie, Fig.18 As shown, the pulse signal supplied from the first pulse signal generator SW4A to the head core WH2A, the pulse signal supplied from the second pulse signal generator SW4B to the head core WH2B, and the pulse signal supplied from the third pulse signal generator SW4C to the head core WH2C are signals of the same phase.

[0225] In the servo pattern recording process, the magnetic tape MT travels at a constant speed on the transport path SW7 in a state where the position of the gap pattern G1 is aligned with the position of the band-shaped area 61 corresponding to the servo band SB3, the position of the gap pattern G2 is aligned with the position of the band-shaped area 61 corresponding to the servo band SB2, and the position of the gap pattern G3 is aligned with the position of the band-shaped area 61 corresponding to the servo band SB1. Then, in this state, the pulse signal for the servo pattern 58A and the pulse signal for the servo pattern 58B are alternately supplied to the head core WH2A, the head core WH2B, and the head core WH2C.

[0226] When the pulse signal for the servo pattern 58A is supplied to the head cores WH2A, WH2B, and WH2C in phase, the servo pattern 58A is recorded on the servo band SB3, servo band SB2, and servo band SB1 in a state of being deviated at a predetermined interval in the long-side direction LD of the magnetic tape MT. Furthermore, when the pulse signal for the servo pattern 58B is supplied to the head cores WH2A, WH2B, and WH2C in phase, the servo pattern 58B is recorded on the servo band SB3, servo band SB2, and servo band SB1 in a state of being deviated at a predetermined interval in the long-side direction LD of the magnetic tape MT.

[0227] Here, reference Fig. 20 The geometric characteristics on the surface WH1A of the gap pattern G will be described.

[0228] As an example, Fig. 20As shown, the geometric characteristics on the surface WH1A of the gap pattern G can be expressed using the virtual straight line region pair 68. The virtual straight line region pair 68 is composed of a virtual straight line region 68A and a virtual straight line region 68B.

[0229] The imaginary straight line region pair 68 is a pair having Fig.19 The virtual straight line region pair 68 has the same geometric characteristics as the gap pattern G. The virtual straight line region pair 68 is a virtual straight line region pair used for convenience in explaining the geometric characteristics on the surface WH1A of the gap pattern G, and is not an actual straight line region pair.

[0230] In this embodiment, for example, the imaginary straight line region 68A has Fig.19 The imaginary straight line region 68B has the same geometric characteristics as the straight line region G1A shown in FIG. Fig.19 The straight line region G1B shown has the same geometrical properties.

[0231] A center O2 is provided in the virtual straight line region pair 68. For example, the center O2 is the center of a line segment L2 connecting the center of the virtual straight line region 68A and the center of the virtual straight line region 68B.

[0232] The imaginary straight line region 68A and the imaginary straight line region 68B are inclined with respect to the imaginary straight line C1 in line symmetry. Here, when the symmetry axis SA2 of the imaginary straight line region 68A and the imaginary straight line region 68B is inclined at an angle b (for example, 10 degrees) with respect to the imaginary straight line C1 with the center O2 as the rotation axis, the entire imaginary straight line region pair 68 is inclined with respect to the imaginary straight line C1. Fig.10 Compared with the imaginary linear region pair 62 shown in FIG. 1 , insufficient portions and unnecessary portions are generated in the imaginary linear region pair 68. Here, the insufficient portions refer to the portions that are insufficient when the servo pattern recording head WH records the servo pattern 58 on the magnetic tape MT, and the unnecessary portions refer to the portions that are unnecessary when the servo pattern recording head WH records the servo pattern 58 on the magnetic tape MT. Fig. 20 In the example shown, a mode in which insufficient portions and unnecessary portions are generated in the virtual straight line region 68B is shown.

[0233] Therefore, by supplementing the insufficient portion and removing the unnecessary portion, the positions of both ends of the virtual straight line region 68A and the positions of both ends of the virtual straight line region 68B are aligned with each other in the direction WD1.

[0234] The geometrical characteristics of the imaginary straight line region pair 68 obtained in this way (i.e., the geometrical characteristics of the imaginary gap pattern) are equivalent to the geometrical characteristics of the actual gap pattern G. That is, on the surface WH1A (reference Fig.19) is formed with a gap pattern G having geometric characteristics equivalent to the geometric characteristics of the virtual straight line region pair 68 obtained by aligning the positions of both ends of the virtual straight line region 68A with the positions of both ends of the virtual straight line region 68B with respect to the direction WD1.

[0235] in addition, Figures 18 to 20 The structure shown is only an example, and even with other structures, the servo band SB can be formed on the magnetic tape MT.

[0236] Next, the operation of the magnetic tape system 10 will be described.

[0237] The magnetic tape MT manufactured by the servo writer SW is contained in the tape cassette 12. The tape drive 14 is loaded in the tape cassette 12. In the tape drive 14, when the magnetic tape MT is subjected to magnetic element unit 42 (refer to Figure 3 and Fig.16 ) during magnetic processing, the magnetic tape MT is pulled out from the tape cassette 12, and the servo pattern 58 in the servo band SB is read by the servo reading element SR of the magnetic head 28.

[0238] like Fig. 9 and Fig.10 As shown in FIG. 1 , the linear magnetized regions 60A1 and 60A2 included in the servo pattern 58A of the servo band SB recorded on the magnetic tape MT are inclined in opposite directions relative to the imaginary straight line C1. Fig.14 As shown, the magnetic head 28 is also moved upstream on the magnetic tape MT at an angle β (i.e., from Fig.14 When viewed from the paper surface side, the servo pattern 58A is tilted at an angle β) in the counterclockwise direction. In this state, when the servo pattern 58A is read by the servo read element SR, the angle formed by the linear magnetized region 60A1 and the servo read element SR and the angle formed by the linear magnetized region 60A2 and the servo read element SR become close to each other, so that the deviation of the servo signal caused by the azimuth loss is smaller than the deviation generated between the servo signal derived from the linear magnetized region 54A1 included in the conventional servo pattern 52A and the servo signal derived from the linear magnetized region 54A2 included in the conventional servo pattern 52A.

[0239] As a result, the deviation between the servo signal from the linear magnetized region 60A1 and the servo signal from the linear magnetized region 60A2 is reduced compared to the deviation between the servo signal from the linear magnetized region 54A1 included in the conventional servo pattern 52A and the servo signal from the linear magnetized region 54A2 included in the conventional servo pattern 52A, thereby making it possible to obtain a servo signal with higher reliability than the servo signal obtained by the conventional servo pattern 52A (hereinafter, this effect is also referred to as the "first effect"). In addition, as Fig.14As shown, the magnetic head 28 is directed upstream on the magnetic tape MT at an angle β (i.e., from Fig.14 When the servo pattern 58B is read by the servo reading element SR in a state tilted at an angle β) in the counterclockwise direction when viewed from the surface side of the paper, the same effect as the first effect is obtained (hereinafter, this effect is also referred to as the "second effect").

[0240] In the width direction WD, if the positions of both ends of the linear magnetized region 60A1 are not aligned with the positions of both ends of the linear magnetized region 60A2, one end of the linear magnetized region 60A1 can be read by the servo read element SR but one end of the linear magnetized region 60A2 cannot be read, or the other end of the linear magnetized region 60A1 can be read by the servo read element SR but the other end of the linear magnetized region 60A2 cannot be read.

[0241] Therefore, in the magnetic tape MT according to the present embodiment, in the servo band SB, the positions of both ends of the linear magnetized region 60A1 (i.e., the positions of both ends of each of the five magnetized straight lines 60A1a) and the positions of both ends of the linear magnetized region 60A2 (i.e., the positions of both ends of each of the five magnetized straight lines 60A2a) are aligned with each other in the width direction WD. Therefore, when the servo pattern 58A is read by the servo read element SR, the linear magnetized regions 60A1 and 60A2 can be appropriately read by the servo read element SR, compared with a case where the positions of both ends of the linear magnetized region 60A1 and the positions of both ends of the linear magnetized region 60A2 are not aligned with each other in the width direction WD. As a result, a servo signal with high reliability can be obtained, compared with a case where the positions of both ends of the linear magnetized region 60A1 and the positions of both ends of the linear magnetized region 60A2 are not aligned with each other in the width direction WD (hereinafter, this effect is referred to as "third effect"). Furthermore, when the servo pattern 58B is read by the servo read element SR, the same effect as the third effect can be obtained (hereinafter, this effect is also referred to as the “fourth effect”).

[0242] like Fig. 9 and Fig.10As shown, although the gradient of the linear magnetized region 60A1 with respect to the imaginary straight line C1 and the gradient of the linear magnetized region 60A2 with respect to the imaginary straight line C1 are steep, if the total length of the linear magnetized region 60A1 is made longer than the total length of the linear magnetized region 60A2, a portion that can be read by the servo read element SR and a portion that cannot be read are generated between the linear magnetized region 60A1 and the linear magnetized region 60A2. Furthermore, even when the total length of the linear magnetized region 60B1 is made longer than the total length of the linear magnetized region 60B2, a portion that can be read by the servo read element SR and a portion that cannot be read are generated between the linear magnetized region 60B1 and the linear magnetized region 60B2. Therefore, in the magnetic tape MT according to the present embodiment, the total length of the linear magnetized region 60A1 is made shorter than the total length of the linear magnetized region 60A2, and the total length of the linear magnetized region 60B1 is made longer than the total length of the linear magnetized region 60B2. Thus, the servo read element SR can appropriately read the linear magnetized regions 60A1 and 60A2 and the servo read element SR can appropriately read the linear magnetized regions 60B1 and 60B2 (hereinafter, this effect is referred to as “fifth effect”).

[0243] Furthermore, in the magnetic tape MT according to the present embodiment, the linear magnetized region 60A1 is a set of five magnetized straight lines 60A1a, and the linear magnetized region 60A2 is a set of five magnetized straight lines 60A2a. Furthermore, the linear magnetized region 60B1 is a set of four magnetized straight lines 60B1a, and the linear magnetized region 60B2 is a set of four magnetized straight lines 60B2a. Therefore, compared with the case where each linear magnetized region is composed of one magnetized straight line, the amount of information obtained from the servo pattern 58 can be increased, and as a result, high-precision servo control can be achieved (hereinafter, this effect is referred to as the "sixth effect").

[0244] Furthermore, in the magnetic tape MT according to the present embodiment, the geometrical characteristics of the linear magnetized region pair 60A on the magnetic tape MT correspond to the following geometrical characteristics: when the entirety of the virtual linear region pair 62 is tilted relative to the virtual straight line C1 by tilting the axis of symmetry SA1 of the virtual linear region pair 62 relative to the virtual straight line C1, the positions of both ends of the virtual linear region 62A and the positions of both ends of the virtual linear region 62B are aligned in the width direction WD. Therefore, compared with the case where the servo reading element SR reads the servo pattern 52A having the conventionally known geometrical characteristics, the deviation between the servo signal derived from the linear magnetized region 60A1 and the servo signal derived from the linear magnetized region 60A2 can be reduced. As a result, a servo signal with higher reliability can be obtained compared with the servo signal obtained from the servo pattern 52A having the conventionally known geometrical characteristics (hereinafter, this effect is referred to as the "seventh effect").

[0245] The linear magnetized region pair 60B is different from the linear magnetized region pair 60A only in that the linear magnetized region 60B1 is replaced by the linear magnetized region 60A1, and the linear magnetized region 60B2 is replaced by the linear magnetized region 60A2. The linear magnetized region pair 60B thus configured is also read by the servo reading element SR in the same manner as the linear magnetized region pair 60A. Therefore, compared with the case where the servo pattern 52B having the conventionally known geometric characteristics is read by the servo reading element SR, the deviation between the servo signal derived from the linear magnetized region 60B1 and the servo signal derived from the linear magnetized region 60B2 can be reduced. As a result, a servo signal with high reliability can be obtained compared with the servo signal obtained from the servo pattern 52B having the conventionally known geometric characteristics (hereinafter, this effect is also referred to as the "eighth effect").

[0246] In the present embodiment, a pair of servo patterns 58 corresponding to each other between the servo bands SB are read by the servo reading elements SR1 and SR2 included in the magnetic head 28. In the present embodiment, the magnetic head 28 is used in a state of being tilted on the magnetic tape MT (see Figure 14 to Figure 16 ). Here, if the pair of servo patterns 58 corresponding to the servo bands SB are not arranged to be offset at a predetermined interval in the longitudinal direction LD of the magnetic tape MT, a time difference occurs between the timing of reading one of the pair of servo patterns 58 corresponding to the servo bands SB and the timing of reading the other servo pattern 58. Therefore, in the magnetic tape MT involved in the present embodiment, the servo patterns 58 corresponding to the servo bands SB are offset at a predetermined interval in the longitudinal direction LD of the magnetic tape MT between the servo bands SB adjacent to each other in the width direction WD. As a result, compared with the case where the pair of servo patterns 58 corresponding to the servo bands SB adjacent to each other in the width direction WD are not arranged to be offset at a predetermined interval, the time difference generated between the timing of reading one of the pair of servo patterns 58 corresponding to the servo bands SB and the timing of reading the other servo pattern 58 can be reduced (hereinafter, this effect is referred to as the "ninth effect").

[0247] In this embodiment, the servo band SB is composed of a plurality of frames 56 (see Fig. 9 and Fig.12 ) is divided. The frame 56 is defined by a pair of servo patterns 58 (i.e., servo patterns 58A and 58B). Furthermore, in the present embodiment, a pair of servo patterns 58 included in a pair of frames 56 that are in a corresponding relationship between adjacent servo bands SB in the width direction WD are read by servo reading elements SR1 and SR2 included in the magnetic head 28. Furthermore, in the present embodiment, the magnetic head 28 is used in a state of being skewed on the magnetic tape MT (refer to Figure 14 to Figure 16Here, if the pair of servo patterns 58 included in the pair of frames 56 corresponding to the servo bands SB adjacent in the width direction WD are not arranged offset at a predetermined interval in the longitudinal direction LD of the magnetic tape MT, a time difference occurs between the timing of reading one of the pair of servo patterns 58 and the timing of reading the other servo pattern 58. Therefore, in the magnetic tape MT involved in the present embodiment, the pair of servo patterns 58 included in the pair of frames 56 corresponding to the servo bands SB adjacent in the width direction WD are offset at a predetermined interval in the longitudinal direction LD of the magnetic tape MT. As a result, compared with the case where the pair of frames 56 corresponding to the servo bands SB adjacent in the width direction WD are not arranged offset at a predetermined interval, the time difference generated between the timing of reading one of the pair of servo patterns 58 included in the pair of frames 56 corresponding to the servo bands SB adjacent in the width direction WD and the timing of reading the other servo pattern 58 can be reduced (hereinafter, this effect is referred to as "the tenth effect").

[0248] In this embodiment, if Fig.12 As shown in FIG. 1 , the predetermined interval is defined by the angle α formed by the imaginary straight line C1 and the frames 56 that are not in a corresponding relationship between the adjacent servo bands SB in the width direction WD, the servo band pitch, and the total length of the long side of the frame 56. That is, the predetermined interval is defined by the formula (1) and is calculated based on the formula (1). Therefore, compared with the case where the predetermined interval is defined without using the angle α, the servo band pitch, and the total length of the long side of the frame 56, the predetermined interval can be obtained more easily (hereinafter, this effect is referred to as the "eleventh effect").

[0249] In this embodiment, the servo signal (see FIG. 1 ) which is the result of reading the servo pattern 58 by the servo reading element SR is detected using the autocorrelation coefficient. Fig.16 ). Thus, compared with the case where the servo signal is detected using only a method of determining whether the signal level exceeds a threshold value, the servo signal can be detected with high accuracy (hereinafter, this effect is referred to as a "twelfth effect").

[0250] In the present embodiment, the servo band SB is formed by alternately recording the servo pattern 58A and the servo pattern 58B on the band-shaped area 61 along the long side direction LD. A virtual straight line C5 is set on the plurality of servo patterns 58 arranged on the servo band SB along the long side direction LD. The virtual straight line C5 is set at a position where the relationship that the distance D1 becomes half of the distance D2 holds. Then, the width SWD of the servo band SB is set to a length that is consistent with the distance D3 and the distance D4. Therefore, for example, in the case where insufficient parts and unnecessary parts are generated by tilting the virtual linear areas 62A and 62B at an angle a with respect to the virtual straight line C1 with the center O1 as the rotation axis, the width SWD of the servo band SB can be set to an appropriate length compared to the case where the insufficient parts are simply supplemented and the unnecessary parts are removed. As a result, servo control, skew angle control, and / or tension control can be performed with high precision (hereinafter, this effect is referred to as the "13th effect").

[0251] In the present embodiment, the distance between the position P1 and the position P2 is the distance D1, and the distance between the position P1 and the position P3 is the distance D2. The imaginary straight line C5 is set at a position where the relationship that the distance D1 is half of the distance D2 is established, and the width SWD of the servo band SB is set to a length that is equal to the distance D3 and the distance D4. In the present embodiment, as the position P1, the position where the magnetization straight line 60A1a located at one end of the long side direction LD among all the magnetization straight lines 60A1a included in the linear magnetization region 60A1 intersects with the imaginary straight line C5 is used. And, as the position P2, the position where the magnetization straight line 60A2a located at one end of the long side direction LD among all the magnetization straight lines 60A2a included in the linear magnetization region 60A2 intersects with the imaginary straight line C5 is used. And, as the position P3, the position where the magnetization straight line 60B1a located at one end of the long side direction LD among all the magnetization straight lines 60B1a included in the linear magnetization region 60B1 intersects with the imaginary straight line C5 is used. Thus, in the magnetic tape MT according to the present embodiment, the width SWD of the servo band SB is set to an appropriate length compared to the case where the position randomly selected from the linear magnetized region 60A1 is set to the position P1, the position randomly selected from the linear magnetized region 60A2 is set to the position P2, and the position randomly obtained from the linear magnetized region 60B1 is set to the position P3. Therefore, it is possible to realize high-precision reading of the servo band SB by the servo read element SR (hereinafter, this effect is referred to as the "fourteenth effect").

[0252] In the present embodiment, the number of magnetized straight lines 60A1a and 60A2a is the same, the number of magnetized straight lines 60A1a and 60B1a is different, and the number of magnetized straight lines 60A2a and 60B2a is different. Therefore, in the magnetic tape MT according to the present embodiment, even if the number of magnetized straight lines 60A1a and 60A2a is the same, the number of magnetized straight lines 60A1a and 60B1a is different, and the number of magnetized straight lines 60A2a and 60B2a is different, the width SWD of the servo band SB is set to an appropriate length. As a result, the servo read element SR can read the servo band SB with high accuracy (hereinafter, this effect is referred to as the "fifteenth effect").

[0253] In the present embodiment, a plurality of servo bands SB are formed at equal intervals along the width direction WD. Therefore, in the magnetic tape MT according to the present embodiment, the width SWD of each of the plurality of servo bands SB is set to an appropriate length. As a result, it is possible to achieve high-precision reading of the servo bands SB by the servo reading element SR (hereinafter, this effect is referred to as the "sixteenth effect").

[0254] [Other Modifications]

[0255] In the above embodiment, the magnetic tape system 10 in which the magnetic tape cartridge 12 is freely insertable and removable relative to the magnetic tape drive 14 is exemplified, but the technology of the present invention is not limited thereto. For example, even in a magnetic tape system in which at least one magnetic tape cartridge 12 is pre-loaded in the magnetic tape drive 14 (i.e., a magnetic tape system in which at least one magnetic tape cartridge 12 is pre-integrated with the magnetic tape drive 14), the technology of the present invention is also applicable.

[0256] In the above embodiment, a single magnetic head 28 is illustrated, but the technology of the present invention is not limited to this. For example, a plurality of magnetic heads 28 may be located on the magnetic tape MT. For example, a read magnetic head 28 and at least one write magnetic head 28 may be located on the magnetic tape MT. The read magnetic head 28 may be used to verify data recorded in the data band DB by the write magnetic head 28. Furthermore, a magnetic head equipped with a read magnetic element unit 42 and at least one write magnetic element unit 42 may be located on the magnetic tape MT.

[0257] The recorded contents and illustrated contents shown above are detailed descriptions of the parts involved in the technology of the present invention, which are only an example of the technology of the present invention. For example, the description related to the above-mentioned structure, function, action and effect is a description related to an example of the structure, function, action and effect of the parts involved in the technology of the present invention. Therefore, it is self-evident that unnecessary parts can be deleted, new elements can be added, or replacements can be made to the recorded contents and illustrated contents shown above without departing from the main purpose of the technology of the present invention. In addition, in order to avoid complexity and facilitate understanding of the parts involved in the technology of the present invention, the descriptions related to the technical common sense that does not need to be specifically explained in terms of the technology that can implement the present invention are omitted in the recorded contents and illustrated contents shown above.

[0258] In this specification, "A and / or B" has the same meaning as "at least one of A and B". That is, "A and / or B" means that it can be only A, only B, or a combination of A and B. Furthermore, in this specification, when three or more items are expressed by connecting with "and / or", the same thinking as "A and / or B" is also applicable.

[0259] All documents, patent applications, and technical standards described in this specification are incorporated herein by reference to the same extent as if each individual document, patent application, and technical standard was specifically and individually indicated to be incorporated by reference.

Claims

1. A magnetic tape having a servo band, wherein: On the servo tape, a plurality of servo patterns are recorded along the long side direction of the magnetic tape. The servo pattern is at least one linear magnetized region pair, The pair of linear magnetized regions is a first linear magnetized region magnetized in a linear shape and a second linear magnetized region magnetized in a linear shape. The first linear magnetized region and the second linear magnetized region are inclined in opposite directions with respect to a first imaginary straight line along the width direction of the magnetic tape. The first linear magnetized region has a steeper inclination angle with respect to the first imaginary straight line than the second linear magnetized region. With respect to the width direction of the magnetic tape, positions of both ends of the first linear magnetized region are aligned with positions of both ends of the second linear magnetized region. On the servo band, as the plurality of servo patterns, a first servo pattern and a second servo pattern are alternately arranged along the long side direction, In the plurality of servo patterns, an imaginary line is set that crosses the plurality of servo patterns along the long side direction. The first servo pattern has a first position and a second position intersecting the imaginary line, The second servo pattern has a third position intersecting the imaginary line, The first position is a position where the imaginary line intersects the first linear magnetized region of the first servo pattern. The second position is a position where the imaginary line intersects the second linear magnetized region of the first servo pattern. The third position is a position where the imaginary line intersects the first linear magnetized region of the second servo pattern. The imaginary line is set at a position where a relationship that a first distance is half of a second distance holds true, the first distance being the distance between the first position and the second position between the first servo pattern and the second servo pattern adjacent to each other in the long side direction, and the second distance being the distance between the first position and the third position, The width of the servo band is set to a length such that a distance from the imaginary line to one end of the servo band in the width direction coincides with a distance from the imaginary line to the other end of the servo band in the width direction.

2. The magnetic tape according to claim 1, wherein The first linear magnetized region is a collection of a plurality of first magnetized straight lines. The second linear magnetization region is a collection of a plurality of second magnetization straight lines. The first position is a position where a first magnetization straight line located at one end in the long-side direction among the plurality of first magnetization straight lines included in the first servo pattern on the imaginary line intersects the imaginary line. The second position is a position where a second magnetization straight line located at one end in the longitudinal direction among the plurality of second magnetization straight lines included in the first servo pattern on the imaginary line intersects the imaginary line. The third position is a position where a first magnetization straight line located at one end in the longitudinal direction among the plurality of first magnetization straight lines included in the second servo pattern on the imaginary line intersects the imaginary line.

3. The magnetic tape according to claim 2, wherein: In the servo pattern, the number of the first magnetization straight lines is the same as the number of the second magnetization straight lines. The number of the first magnetization straight lines is different between the first servo pattern and the second servo pattern. The number of the second magnetization straight lines is different between the first servo pattern and the second servo pattern.

4. The magnetic tape according to claim 1, wherein A plurality of the servo bands are formed at a predetermined pitch in the width direction.

5. A magnetic tape cassette comprising: The magnetic tape according to any one of claims 1 to 4; and The casing contains the magnetic tape.

6. A servo pattern recording device comprising: Pulse signal generator; and Servo pattern recording head, The pulse signal generator generates a pulse signal, The servo pattern recording head has a gap pattern, and a magnetic field is applied from the gap pattern to a band-shaped area formed in a band shape along the long side direction of the magnetic tape on the surface of the magnetic tape according to the pulse signal, thereby recording a plurality of servo patterns in the band-shaped area along the long side direction. forming a servo band by recording the plurality of servo patterns in the band-shaped region along the long-side direction, The gap pattern is at least one straight line area pair, One of the pair of straight line areas, i.e., the first straight line area, and the other of the pair of straight line areas, i.e., the second straight line area, are inclined in opposite directions relative to a second imaginary straight line along a direction corresponding to the width direction of the magnetic tape on the surface. The first straight line region has a steeper inclination angle with respect to the second imaginary straight line than the second straight line region. The positions of both ends of the first straight line region and the positions of both ends of the second straight line region are aligned in a direction corresponding to the width direction of the magnetic tape. The servo pattern is at least one linear magnetized region pair, The pair of linear magnetized regions is a first linear magnetized region magnetized in a linear shape and a second linear magnetized region magnetized in a linear shape. The first linear magnetized region and the second linear magnetized region are inclined in opposite directions with respect to a first imaginary straight line along the width direction of the magnetic tape. The first linear magnetized region has a steeper inclination angle with respect to the first imaginary straight line than the second linear magnetized region. With respect to the width direction of the magnetic tape, positions of both ends of the first linear magnetized region are aligned with positions of both ends of the second linear magnetized region. On the servo band, as the plurality of servo patterns, a first servo pattern and a second servo pattern are alternately arranged along the long side direction, In the plurality of servo patterns, an imaginary line is set that crosses the plurality of servo patterns along the long side direction. The first servo pattern has a first position and a second position intersecting the imaginary line, The second servo pattern has a third position intersecting the imaginary line, The first position is a position where the imaginary line intersects the first linear magnetized region of the first servo pattern. The second position is a position where the imaginary line intersects the second linear magnetized region of the first servo pattern. The third position is a position where the imaginary line intersects the first linear magnetized region of the second servo pattern. The imaginary line is set at a position where a relationship that a first distance is half of a second distance holds true, the first distance being the distance between the first position and the second position between the first servo pattern and the second servo pattern adjacent to each other in the long side direction, and the second distance being the distance between the first position and the third position, The width of the servo band is set to a length such that a distance from the imaginary line to one end of the servo band in the width direction coincides with a distance from the imaginary line to the other end of the servo band in the width direction.

7. The servo pattern recording device according to claim 6, wherein: The first linear magnetized region is a collection of a plurality of first magnetized straight lines. The second linear magnetization region is a collection of a plurality of second magnetization straight lines. The first position is a position where a first magnetization straight line located at one end in the long-side direction among the plurality of first magnetization straight lines included in the first servo pattern on the imaginary line intersects the imaginary line. The second position is a position where a second magnetization straight line located at one end in the longitudinal direction among the plurality of second magnetization straight lines included in the first servo pattern on the imaginary line intersects the imaginary line. The third position is a position where a first magnetization straight line located at one end in the longitudinal direction among the plurality of first magnetization straight lines included in the second servo pattern on the imaginary line intersects the imaginary line.

8. The servo pattern recording device according to claim 7, wherein: In the servo pattern, the number of the first magnetization straight lines is the same as the number of the second magnetization straight lines. The number of the first magnetization straight lines is different between the first servo pattern and the second servo pattern. The number of the second magnetization straight lines is different between the first servo pattern and the second servo pattern.

9. The servo pattern recording device according to claim 6, wherein: A plurality of the servo bands are formed at a predetermined pitch in the width direction.

10. A magnetic tape drive comprising: A traveling mechanism for causing the magnetic tape according to any one of claims 1 to 4 to travel along a predetermined path; and a magnetic head having a plurality of servo reading elements for reading the servo pattern on the predetermined path while the magnetic tape is advanced by the advancing mechanism; The plurality of servo reading elements are arranged along the long side direction of the magnetic head. The magnetic head is arranged in a posture in which the longitudinal direction of the magnetic head is inclined with respect to the traveling direction of the magnetic tape.

11. A magnetic tape system comprising: The magnetic tape according to any one of claims 1 to 4; and A magnetic tape drive is equipped with a magnetic head having a plurality of servo reading elements for reading the servo pattern on a predetermined path while the magnetic tape is moving along the predetermined path. The plurality of servo reading elements are arranged along the long side direction of the magnetic head. The magnetic head is arranged in a posture in which the longitudinal direction of the magnetic head is inclined with respect to the traveling direction of the magnetic tape.

12. A detection device comprising a processor, wherein: The processor detects a servo signal, which is a result of reading the servo pattern from the magnetic tape according to any one of claims 1 to 4 by a servo reading element, using an autocorrelation coefficient.

13. A servo pattern recording method comprising the following steps: generating a pulse signal; and A servo pattern recording head having a gap pattern is used to apply a magnetic field from the gap pattern to a band-shaped area formed in a band shape along the long side direction of the magnetic tape on the surface of the magnetic tape, according to the pulse signal, thereby recording a plurality of servo patterns in the band-shaped area along the long side direction. The servo bands are formed by recording the plurality of servo patterns in the long-side direction in the band-shaped region, The gap pattern is at least one straight line area pair, One of the pair of straight line areas, i.e., the first straight line area, and the other of the pair of straight line areas, i.e., the second straight line area, are inclined in opposite directions relative to a second imaginary straight line along a direction corresponding to the width direction of the magnetic tape on the surface. The first straight line region has a steeper inclination angle with respect to the second imaginary straight line than the second straight line region. The positions of both ends of the first straight line region and the positions of both ends of the second straight line region are aligned in a direction corresponding to the width direction of the magnetic tape. The servo pattern is at least one linear magnetized region pair, The pair of linear magnetized regions is a first linear magnetized region magnetized in a linear shape and a second linear magnetized region magnetized in a linear shape. The first linear magnetized region and the second linear magnetized region are inclined in opposite directions with respect to a first imaginary straight line along the width direction of the magnetic tape. The first linear magnetized region has a steeper inclination angle with respect to the first imaginary straight line than the second linear magnetized region. With respect to the width direction of the magnetic tape, positions of both ends of the first linear magnetized region are aligned with positions of both ends of the second linear magnetized region. On the servo band, as the plurality of servo patterns, a first servo pattern and a second servo pattern are alternately arranged along the long side direction, In the plurality of servo patterns, an imaginary line is set that crosses the plurality of servo patterns along the long side direction. The first servo pattern has a first position and a second position intersecting the imaginary line, The second servo pattern has a third position intersecting the imaginary line, The first position is a position where the imaginary line intersects the first linear magnetized region of the first servo pattern. The second position is a position where the imaginary line intersects the second linear magnetized region of the first servo pattern. The third position is a position where the imaginary line intersects the first linear magnetized region of the second servo pattern. The imaginary line is set at a position where a relationship that a first distance is half of a second distance holds true, the first distance being the distance between the first position and the second position between the first servo pattern and the second servo pattern adjacent to each other in the long side direction, and the second distance being the distance between the first position and the third position, The width of the servo band is set to a length such that a distance from the imaginary line to one end of the servo band in the width direction coincides with a distance from the imaginary line to the other end of the servo band in the width direction.

14. A magnetic tape having a plurality of servo patterns recorded thereon by the servo pattern recording device according to any one of claims 6 to 9.

15. A magnetic tape cassette comprising: The magnetic tape of claim 14; and The casing contains the magnetic tape.

16. A magnetic tape drive comprising: A traveling mechanism for causing the magnetic tape of claim 14 to travel along a predetermined path; and a magnetic head having a plurality of servo reading elements for reading the servo pattern on the predetermined path while the magnetic tape is advanced by the advancing mechanism; The plurality of servo reading elements are arranged along the long side direction of the magnetic head. The magnetic head is arranged in a posture in which the longitudinal direction of the magnetic head is inclined with respect to the traveling direction of the magnetic tape.

17. A magnetic tape system comprising: The magnetic tape of claim 14; and A magnetic tape drive is equipped with a magnetic head having a plurality of servo reading elements for reading the servo pattern on a predetermined path while the magnetic tape is moving along the predetermined path. The plurality of servo reading elements are arranged along the long side direction of the magnetic head. The magnetic head is arranged in a posture in which the longitudinal direction of the magnetic head is inclined with respect to the traveling direction of the magnetic tape.

18. A detection device comprising a processor, wherein: The processor detects a servo signal, which is a result of reading the servo pattern from the magnetic tape of claim 14 by a servo reading element, using an autocorrelation coefficient.

19. A method for manufacturing a magnetic tape, comprising the following steps: Recording a plurality of servo patterns on a magnetic tape according to the servo pattern recording method of claim 13; and The magnetic tape is reeled up.

20. An inspection device comprising: The detection device according to claim 12 or 18; and The inspection processor inspects a servo band in which the servo pattern is recorded in the magnetic tape based on the servo signal detected by the detection device.

21. A detection method comprising the following steps: The servo signal, which is a result of reading the servo pattern from the magnetic tape according to any one of claims 1 to 4 and 14 by a servo reading element, is detected using an autocorrelation coefficient.

22. A method of inspection, comprising the following steps: Based on the servo signal detected by the detection method according to claim 21, the servo band in which the servo pattern is recorded is inspected in the magnetic tape.

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