JPH05182111A - Magneto-optical disk device - Google Patents

Abstract

PURPOSE:To prevent the disturbance of a recording mark by holding a perpendicular magnetic head therebetween adjacently to the intrasurface magnetic head and intrasurface magnetizing the end of the recording mark to be recorded on the surface of a magneto-optical recording medium. CONSTITUTION:An intrasurface magnetic head 4 consists of magnetic cores 1 and 2 and cores 1 and 3 constitute the perpendicular magnetic head 5. A coil 6 is wound on the core 1. The coil 6 is used in common by heads 4 and 5. By such constitution, the recording mark recorded on the surface of a magneto-optical recording medium is intrasurface magnetized and the disturbance of the recording mark edge is eliminated. Thus, the recording mark is stabilized, jitter is eliminated and the BER is improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magneto-optical disk device which records and reproduces information by using a laser beam and an external magnetic field and reproduces information by using a laser beam reflected from a magneto-optical recording medium. Regarding

[0002]

2. Description of the Related Art Conventionally, as a magneto-optical disk device having a magnetic field modulation function and an overwrite function, there is, for example, one disclosed in Japanese Patent Laid-Open No. 1-211302. This is because when overwriting is performed using a magnetic head and a laser beam, a thin film made of a high saturation magnetic flux density material is provided on the end surface of the magnetic core, which is opposite to the magneto-optical recording medium. The external magnetic field that acts can be further increased, and the magnetic field generation efficiency can be greatly increased.

[0003]

In the conventional apparatus as described above, when recording is performed on the magneto-optical recording medium using the magnetic head, when the shape of the recorded recording marks 11 becomes high density, FIG. As shown in (b), the crescent-shaped mark is crushed and the jitter is deteriorated, which deteriorates the byte error rate (BER). As described above, since the conventional magnetic head has not been improved so much, when recording is performed using such a magnetic head, the shape of the end portion of the recorded recording mark 11 is disturbed, and as a result, jitter and BER are reduced. There is a problem of getting worse.

[0004]

According to a first aspect of the invention, information is recorded and erased by irradiating a surface of a magneto-optical recording medium with a laser beam in a state where an external magnetic field is applied by a magnetic head. At the same time, in the magneto-optical disk device for irradiating the surface of the magneto-optical recording medium with the laser beam and reproducing the information by using the reflected light, the magnetic head includes an in-plane magnetic head and the in-plane magnetic head. A part of which is formed by a perpendicular magnetic head which is held by its in-plane magnetic head.

According to the invention of claim 2, in the invention of claim 1, the gap of the perpendicular magnetic head is present between the gaps of the in-plane magnetic head.

According to the invention of claim 3, in the invention of claim 1, the in-plane magnetic head and the perpendicular magnetic head are:
It consists of two magnetic cores each across the gap, and
One of the two magnetic cores was shared.

[0007]

According to the invention of claim 1, the vertical magnetic head is held adjacent to the in-plane magnetic head.
It is possible to in-plane magnetize the end of the recording mark recorded on the surface of the magneto-optical recording medium and eliminate the sagging of only the recording mark.

According to the second aspect of the invention, since the same gap exists, the recording mark can be tilted in the plane when the mark is formed and the mark can be stabilized.

According to the third aspect of the invention, since one of the magnetic cores of the in-plane magnetic head and the perpendicular magnetic head is shared, the manufacturing process can be simplified.

[0010]

An embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows a configuration of a magnetic core portion of a magnetic head. The magnetic core portion includes two large-shaped magnetic cores 1 and 2 provided on both left and right sides, and a magnetic core 3 formed on the surface of the magnetic core 2 between the magnetic cores 1 and 2.
It has become. In this case, magnetic core 1 and magnetic core 2
And constitute an in-plane magnetic head 4, and the magnetic core 1 and the magnetic core 3 constitute a perpendicular magnetic head 5. A coil 6 is wound around the magnetic core 1. This coil 6
Is commonly used for the in-plane magnetic head 4 and the perpendicular magnetic head 5.

As a method of manufacturing such a magnetic core part, after the magnetic core 3 is formed on the surface of the magnetic core 2 by vapor deposition or sputtering, glass 7 (low melting point glass) is used. It is manufactured by welding the magnetic core 1. The track width Tw (see FIG. 2) of the magnetic core 3 is formed by masking during vapor deposition or sputtering according to the laser beam diameter, or by etching or the like.

FIG. 2 shows the structure of the magnetic gap portion of the magnetic core portion. Gap1 and Gap3 are gaps for the in-plane magnetic head, and Gap2 is a gap for the perpendicular magnetic head. The magnetic cores 1 and 2 have high permeability M
An n-Zn ferrite material (bulk) is used, and the magnetic core 3 is made of high magnetic permeability permalloy or sendust. In this case, Gap 1 to 3 are each glass-molded, and the glass 7 is a low-melting glass (melting point 6 as described above.
A material of about 00 ° C is used.

In such a structure, FIG. 3 shows an example in which the magnetic core portion of FIG. 1 is incorporated in the slider 8 to form the flying type magnetic head 9. in this case,
The slider 8 is made of a non-magnetic material (such as barium titanate ceramics) and is fixed by adhering the magnetic core portion with an adhesive or the like to form a head.

Recording is performed by irradiating a laser beam on the surface on which the flying magnetic head 9 is placed in proximity to the surface of a magneto-optical recording medium (not shown). It can be performed. Figure 4
(A) shows the recording mark 10 thus recorded.
The shape of (vertical component) is shown. On the contrary,
FIG. 4B shows the shape of the recording mark 11 when recording is performed using the conventional magnetic head. These Figure 4
As can be seen by comparing (a) and (b), it can be seen that the recording mark 10 recorded by the method of the present embodiment has less disturbance at the end of the mark. Therefore, by stabilizing the shape of the recording mark 10 in this way,
As shown in (1), the value of jitter δ is improved, and the value of BER can be further improved.

Further, in this embodiment, by setting the track width Tw of the perpendicular magnetic head 5 shown in FIG. 2 to 1 μm or less, the end of the recording mark 10 is inclined in the plane when the mark is formed and the mark is stabilized. However, this improves the jitter, and the BER value can be further improved.

Next, a specific example will be described. First, as the first specific example, the design conditions of the magnetic core portion and the magneto-optical recording medium are set as follows.

Magnetic cores 1 and 2: Mn-Zn ferrite, high magnetic permeability μ≈2000 (1 MHz), saturation magnetization 4000 Gaus Magnetic core 3: Permalloy High magnetic permeability μ≈3000 (1 MHz), saturation magnetization 5000 Gaus Gap1, 3≈25 μm, Gap2 ≒ 20 [mu] m inductance: 7μH (1MHz) magneto-optical recording medium: PC board recording film _{(.. Tb 0 3 Dy 0} 7) 24 Fe 68 Co 8 overcoat (UV protective layer) BER value by such a design condition, BER = 0.9 × 10 ⁶ (1)

As a second specific example, the design conditions of the magnetic core portion and the magneto-optical recording medium are set as follows.

Magnetic cores 1 and 2: Mn-Zn ferrite, high magnetic permeability μ≈2000 (1 MHz) Saturation magnetization 4000 Gaus Magnetic core 3: Sendust High magnetic permeability μ≈6000 (1 MHz) Saturation magnetization 8000 Gaus Gap1, 3≈40 μm, Gap2 ≒ 25 [mu] m inductance: 11μH (1MHz) magneto-optical recording medium: PC board recording film _{(.. Tb 0 3 Dy 0} 7) 24 Fe 68 Co 8 overcoat (UV protective layer) BER value by such a design condition, BER = 0.7 × 10 ⁶ (2)

As an example of comparison with these two specific examples, a monolithic type (Mn-Z) magnetic head is used.
The magnetic head of n) is used, and the magneto-optical recording medium of the same type as the first specific example is used.

Under such design conditions, the value of BER is BER = 0.9 × 10 to ⁵ (3)

Therefore, as can be seen by comparing equations (1) to (3), the values of equations (1) and (2) are improved by an order of magnitude over the values of equation (3). Recognize.

[0023]

According to the first aspect of the present invention, information is recorded and erased by irradiating a surface of a magneto-optical recording medium with a laser beam in a state where an external magnetic field is applied by a magnetic head. In a magneto-optical disk device that irradiates a beam onto a surface of a magneto-optical recording medium and reproduces information by using the reflected light, the magnetic head is provided in an in-plane magnetic head and adjacent to the in-plane magnetic head. Since a part was formed by the perpendicular magnetic head held by the in-plane magnetic head, the edge of the recording mark recorded on the surface of the magneto-optical recording medium was in-plane magnetized, and the disorder of the edge of the recording mark was disturbed. By doing so, the recording mark can be stabilized, jitter can be improved, and the bid error rate can be improved.

According to a second aspect of the invention, in the first aspect of the invention, the gap of the perpendicular magnetic head exists between the gaps of the in-plane magnetic heads, so that the recording mark is in-plane when the mark is formed. It is possible to stabilize the mark by inclining, which improves the jitter and improves the bid error rate.

According to a third aspect of the present invention, in the first aspect of the present invention, the in-plane magnetic head and the perpendicular magnetic head each include two magnetic cores with a gap between them, and of the two magnetic cores. Since one of them is shared, the manufacturing process can be simplified and the cost can be reduced.

[Brief description of drawings]

FIG. 1 is a perspective view showing a magnetic core portion according to an embodiment of the present invention.

FIG. 2 is a schematic diagram showing a configuration of a magnetic gap portion.

FIG. 3 is a perspective view showing the shape of a floating magnetic head.

FIG. 4 is a schematic diagram showing a state of recording marks.

FIG. 5 is a characteristic diagram showing a relationship between BER and jitter δ.

[Explanation of symbols]

 1, 2, 3 Magnetic core 4 In-plane magnetic head 5 Perpendicular magnetic head

Claims (3)

[Claims] 1. Information is recorded and erased by irradiating a surface of a magneto-optical recording medium with a laser beam in a state where an external magnetic field is applied by a magnetic head, and the laser beam is irradiated onto the surface of the magneto-optical recording medium. In a magneto-optical disk device that irradiates onto the top and reproduces information using the reflected light,
A magneto-optical disk device, wherein the magnetic head comprises an in-plane magnetic head and a perpendicular magnetic head adjacent to the in-plane magnetic head and partially sandwiched by the in-plane magnetic head. 2. The gap of the perpendicular magnetic head exists between the gaps of the in-plane magnetic head.
The magneto-optical disk device described. 3. The in-plane magnetic head and the perpendicular magnetic head are
It consists of two magnetic cores each across the gap, and
2. The magneto-optical disk device according to claim 1, wherein one of the two magnetic cores is shared.