JPH024052B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a magnetic recording/reproducing apparatus such as a video tape recorder suitable for short wavelength recording.

Conventional structure and its problems Traditionally, in magnetic recording and reproducing devices such as video tape recorders, longitudinal magnetization (in-plane magnetization)
was common. It is known that recording demagnetization occurs in longitudinal magnetization during short wavelength recording. For this reason, in video tape recorders and the like, recording demagnetization increases when the recording wavelength reaches 1 μm, making it difficult to put shorter wavelength recording into practical use.

On the other hand, perpendicular magnetization systems aimed at recording at even shorter wavelengths have been studied, and many proposals for practical use have been made. However, most of the perpendicular magnetization methods currently proposed require a main magnetic pole and an auxiliary magnetic pole for recording and reproduction, and also require a two-layer film structure of a perpendicular magnetization film and a horizontal magnetization film for the recording medium. There are drawbacks such as a complicated configuration.

Also, so-called TRANSVERSE recording has been proposed, in which the gap width direction of the magnetic head is almost the same as the running direction of the magnetic tape. (Actually, it is thought that only about 3 times more can be recorded and played back.
This did not lead to the realization of significantly shorter wavelength records.

OBJECTS OF THE INVENTION It is an object of the present invention to provide a magnetic recording/reproducing device which eliminates the above-mentioned conventional drawbacks and enables recording at significantly shorter wavelengths.

Composition of the Invention In order to achieve the above object, the present invention has a magnetic recording medium and a magnetic head that moves at a required relative speed with respect to the magnetic recording medium. A magnetic recording/reproducing device using transverse recording in which the direction of position movement is the same as the direction of movement,
This configuration uses a magnetic head with different core widths on both sides of the opposing cores constituting the head gap portion as the magnetic head for reproduction.This eliminates the restriction on the reproduction wavelength due to the gap width, and the transformer Significantly short wavelength recording can be realized by birth recording.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below based on the drawings. FIG. 1 shows a block diagram of essential parts of a tape head system according to the present invention. 1 is a magnetic head, 2 is a magnetic tape, 3
4 is a magnetic head support, and 4 is a coil wound around the magnetic head 1. G1 is a gap portion of the magnetic head 1. An arrow 5 indicates the direction of movement of the magnetic head 1, which is the same direction as the gap width direction of the gap portion G1. In addition, the relative loss of seals is 5.
There is no problem even if the magnetic tape 2 runs in the opposite direction. This is the gap length GA of the gap part G1.
The figure shows a transverse recording with a track width of .

FIG. 2 is a perspective view of the gap G1 of the magnetic head 1 viewed from the lower side in front of the magnetic tape 2. As shown in FIG. In FIG. 2, the front end of the gap G1 of the magnetic head 1 has opposing core ends 6 and 7.
The straight line 8 is a straight line connecting the core ends 6 and 7. At the same time, the rear end portion is composed of a core end 9 and a core end 10 facing each other, and a straight line 11 is a straight line connecting the core end 9 and the core end 10. and,
The straight line 8 and the extension line 12 of the arrow 5 intersect at an angle that is not a right angle, and the straight line 11 and the extension line 12 intersect at a right angle. This is the core width length L ₁ between the opposing cores, that is, core end 6 and core end 9, and core end 7.
This is caused by the fact that the length _L2 of the core width between the core end 10 and the core width L2 are different.

In a tape head system configured like this,
When a recording current as shown in FIG. 3 is passed through the coil 4, a magnetization pattern as shown in FIG. 4 is obtained. In FIG. 4, 13 indicates a recording track, and 14 indicates a magnetization vector. This is what is called transverse recording.

When playing back conventional transverse recordings,
As illustrated in FIG. 5 (a perspective view seen from the same direction as FIG. 2), the length L ₃ of the core width between the core end 15 and the core end 17, the core end 16 and the core end 18, The magnetic head 1 has a gap width L (L=L ₃ =L ₄ ), in which the length L ₄ of the core width between
9 is used, reproduction frequency characteristics as shown in FIG. 6 can be obtained. Point A in FIG. 6 is the valley of the frequency characteristic, and this is the playback gap loss that occurs when the wavelength of the signal recorded on the magnetic tape 2 and the gap width L become equal.
Signals with shorter wavelengths (higher frequency signals)
However, as shown in the figure, there are multiple playback gaps and losses, so it cannot be used for actual use (recording and playback).

However, as shown in FIG _{. 2} , when the recorded track 13 shown in _FIG . The reproduction frequency characteristic is the 7th
As shown in the figure, a product without so-called valleys can be obtained. This removes the limitation on the reproduction wavelength due to the gap width, making it possible to reproduce significantly shorter wavelength symbols by transverse recording. This recording wavelength is sufficiently shorter than the commonly used longitudinal magnetization.

Here, it is considered that the reason why no valley occurs in the reproduction frequency characteristic is that the angle of the front end of the gap formed by the core ends 6 and 7 is different from the angle of the domain wall of the recorded signal. Note that this also applies to a magnetic head (not shown) configured such that the angle at the front end of the gap is the same as the angle of the domain wall of the recorded signal, and the angle at the rear end of the gap is different from the angle of the domain wall of the recorded signal. You can get the following effect. These magnetic heads are obtained in transverse recording by making the core widths of opposing cores that constitute a head gap in a reproducing magnetic head different in length.

Effects of the Invention According to the invention described above, it is possible to eliminate the restriction on reproduction wavelength due to the gap width, and to realize significantly short wavelength recording by transverse recording. Furthermore, the present invention has the feature that it does not require a special head or a special medium unlike the perpendicular magnetization method, and its industrial value is extremely large.

[Brief explanation of drawings]

FIG. 1 is a schematic perspective view of essential parts showing an example of the structure of a tape head system according to the present invention, FIG. 2 is a schematic perspective view showing an example of the structure of the magnetic head in FIG. 1,
Figure 3 is a signal waveform diagram showing an example of a recording signal;
The figure is a schematic perspective view showing an example of the recording pattern recorded on the magnetic tape used in the present invention, FIG. 5 is a schematic perspective view of the main part showing an example of the configuration of a conventional magnetic head, and FIG. FIG. 7 is a schematic characteristic diagram showing an example of reproduction frequency characteristics when a magnetic head is used. FIG. 7 is a schematic characteristic diagram showing an example of reproduction frequency characteristics when a magnetic head is used in the present invention. 1... Magnetic head, 2... Magnetic tape, 4... Coil, 5... Relative movement direction, 6, 7, 9, 10... Core end, G ₁ ... Head/gap portion, L ₁ , L ₂ ... Length of core width , GA...Gap length.

Claims (1)

[Scope of Claims] 1. A magnetic recording medium and a magnetic head that moves at a required relative speed with respect to the magnetic recording medium, and the gap width direction of the magnetic head and the direction of the relative movement are the same direction. A magnetic recording/reproducing device using transverse recording, characterized in that it uses a magnetic head in which the core widths of opposite cores constituting a head gap portion are different in length. magnetic recording/reproducing or reproducing device. 2. The straight line connecting the opposing core ends of the front end of the head gap of the magnetic head is configured to be perpendicular to the direction of relative movement between the magnetic recording medium and the magnetic head, and the head gap of the magnetic head is The magnetic recording and reproducing device according to claim 1, wherein a straight line connecting the opposing core ends of the rear end of the section is configured to form an angle different from a right angle with respect to the relative movement direction. Or a playback device. 3. Construct the straight line connecting the opposing core ends of the front end of the head gap portion of the magnetic head to be at an angle different from a right angle to the direction of relative movement between the magnetic recording medium and the magnetic head, and The magnetic recording/reproducing device according to claim 1, wherein a straight line connecting the opposing core ends of the rear end of the head gap portion of the head gap is arranged to be perpendicular to the direction of relative movement. Or a playback device.