Magnetic tape apparatus

Patent metadata

Field	Value
Publication number	US-2020005818-A1
Application number	US-201916456970-A
Country	US
Kind code	A1
Filing date	Jun 28, 2019
Priority date	Jun 29, 2018
Publication date	Jan 2, 2020
Grant date	—

Abstract

A magnetic tape apparatus includes a magnetic tape, a reading element unit and an extraction unit, in which the magnetic tape includes a non-magnetic support, and a magnetic layer including a ferromagnetic powder and a binding agent on the non-magnetic support, a logarithmic decrement acquired by a pendulum viscoelasticity test performed regarding a surface of the magnetic layer is equal to or smaller than 0.050, and an extraction unit performs a waveform equalization process according to a deviation amount between positions of the magnetic tape and the reading element unit, with respect to each reading result for each reading element, to extract data derived from the reading target track from the reading result.

First claim

What is claimed is:

1 . A magnetic tape apparatus comprising:
a magnetic tape; a reading element unit; and an extraction unit, wherein the magnetic tape includes a non-magnetic support, and a magnetic layer including a ferromagnetic powder and a binding agent on the non-magnetic support, a logarithmic decrement acquired by a pendulum viscoelasticity test performed regarding a surface of the magnetic layer is equal to or smaller than 0.050, the reading element unit includes a plurality of reading elements each of which reads data by a linear scanning method from a specific track region including a reading target track in a track region included in the magnetic tape, and the extraction unit performs a waveform equalization process according to a deviation amount between positions of the magnetic tape and the reading element unit, with respect to each reading result for each reading element, to extract data derived from the reading target track from the reading result.

2 . The magnetic tape apparatus according to claim 1 ,
wherein parts of the plurality of reading elements are overlapped each other in a running direction of the magnetic tape.

3 . The magnetic tape apparatus according to claim 2 ,
wherein the specific track region is a region including the reading target track and adjacent tracks which are adjacent to the reading target track, and each of the plurality of reading elements straddles over both of the reading target track and the adjacent track, in a case where a positional relationship with the magnetic tape is changed.

4 . The magnetic tape apparatus according to claim 1 ,
wherein the plurality of reading elements are disposed in a line in a state of being adjacent to each other, in a width direction of the magnetic tape.

5 . The magnetic tape apparatus according to claim 1 ,
wherein the plurality of reading elements fall in the reading target track in a width direction of the magnetic tape.

6 . The magnetic tape apparatus according to claim 1 ,
wherein the waveform equalization process is performed by using a tap coefficient determined in accordance with the deviation amount.

7 . The magnetic tape apparatus according to claim 6 ,
wherein, regarding each of the plurality of reading elements, a ratio between an overlapping region with the reading target track and an overlapping region with an adjacent track which is adjacent to the reading target track is specified from the deviation amount, and the tap coefficient is determined in accordance with the specified ratio.

8 . The magnetic tape apparatus according to claim 2 ,
wherein the waveform equalization process is performed by using a tap coefficient determined in accordance with the deviation amount.

9 . The magnetic tape apparatus according to claim 8 ,
wherein, regarding each of the plurality of reading elements, a ratio between an overlapping region with the reading target track and an overlapping region with an adjacent track which is adjacent to the reading target track is specified from the deviation amount, and the tap coefficient is determined in accordance with the specified ratio.

10 . The magnetic tape apparatus according to claim 3 ,
wherein the waveform equalization process is performed by using a tap coefficient determined in accordance with the deviation amount.

11 . The magnetic tape apparatus according to claim 10 ,
wherein, regarding each of the plurality of reading elements, a ratio between an overlapping region with the reading target track and an overlapping region with an adjacent track which is adjacent to the reading target track is specified from the deviation amount, and the tap coefficient is determined in accordance with the specified ratio.

12 . The magnetic tape apparatus according to claim 4 ,
wherein the waveform equalization process is performed by using a tap coefficient determined in accordance with the deviation amount.

13 . The magnetic tape apparatus according to claim 12 ,
wherein, regarding each of the plurality of reading elements, a ratio between an overlapping region with the reading target track and an overlapping region with an adjacent track which is adjacent to the reading target track is specified from the deviation amount, and the tap coefficient is determined in accordance with the specified ratio.

14 . The magnetic tape apparatus according to claim 5 ,
wherein the waveform equalization process is performed by using a tap coefficient determined in accordance with the deviation amount.

15 . The magnetic tape apparatus according to claim 14 ,
wherein, regarding each of the plurality of reading elements, a ratio between an overlapping region with the reading target track and an overlapping region with an adjacent track which is adjacent to the reading target track is specified from the deviation amount, and the tap coefficient is determined in accordance with the specified ratio.

16 . The magnetic tape apparatus according to claim 1 ,
wherein the deviation amount is determined in accordance with a result obtained by reading a servo pattern applied to the magnetic tape in advance, by a servo element.

17 . The magnetic tape apparatus according to claim 16 ,
wherein a reading operation by the reading element unit is performed synchronously with a reading operation by the servo element.

18 . The magnetic tape apparatus according to claim 1 ,
wherein the extraction unit includes a two-dimensional FIR filter, and the two-dimensional FIR filter composes each result obtained by performing the waveform equalization process with respect to each reading result for each reading element, to extract data derived from the reading target track from the reading result.

19 . The magnetic tape apparatus according to claim 1 ,
wherein the plurality of reading elements are a pair of reading elements.

20 . The magnetic tape apparatus according to claim 1 ,
wherein the logarithmic decrement is 0.010 to 0.050.

Assignees

• Fujifilm Corp

Inventors

• Kasada Norihito
• Ozawa Eiki
• Musha Atsushi

Classifications

• G11B5/70 Primary

  on a base layer · CPC title

• G11B15/46

  Controlling, regulating, or indicating speed {(dependent on position of tape in reserve, loop G11B15/56, G11B15/58)} · CPC title

• G11B5/70678

  Ferrites · CPC title

• G11B5/09

  Digital recording · CPC title

• G11B5/584 Primary

  for track following on tapes · CPC title