JPH0944918A - Information recorder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To finely vibrate a head on a medium and to obtain a tracking servo signal by forming the head on the free end of a cantilever spring and vibrating the cantilever in a prescribed position on a track. SOLUTION: The head 1 detects interatomic force, magnetic force between the medium and the head 1 or the electric conductivity, dielectric constant, etc., of the medium. Further, on the cantilever spring 2, piezo elements 5, 7 and a pattern electrode 6 are formed on the surface having the head 1 and the surface opposite to it in the form nearly parallel to each other. The cantilever 2 is fixed to the piezo element 11 through a base part spacer 12, and AC sources 16, 17 are connected to the piezo elements 5, 7 through electrodes 8, 10, resistors 13, 14 and a switch 15. The AC sources 16, 17 are provided with the same frequency whose phases are shifted by 180 deg., and AC voltage with opposite phases are applied to the piezo elements 5, 7 by turning the switch 15 on, and the cantilever spring causes twisted vibration. The head 1 vibrates in the direction of an arrow mark 50 according to the vibration.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultra high density information recording device.

[0002]

2. Description of the Related Art As the density of information recording devices has increased, new recording methods have been proposed which exceed the recording density of recording devices that are currently in practical use. One of them is a scanning type
One using a microscope is considered. This uses a probe of a scanning probe microscope as a head, and examples thereof include JP-A-64-53363.

In this method, in order to move the head relatively in the recording area, a method of rotating a disk-shaped recording medium can be considered. When using a disk medium,
As a head tracking servo method, it is possible to follow the conventional sample servo method of an optical disk.

[0004]

When the sample servo system is applied to the head tracking servo, it is necessary to write the marks in a staggered pattern on the recording medium. Here, considering the use of the sample servo system in an ultra-high density recording apparatus having a recording bit size of about 100 nm, it is considered difficult to improve the positional accuracy of the staggered foot mark. Also, writing the marks in a staggered pattern makes it difficult to increase the track density.

[0005]

In the present invention, the head is formed on the free end of a cantilever spring having an exciting mechanism.
The excitation mechanism is formed by a piezo element built in a cantilever spring and a voltage applying device that applies a voltage to the piezo element, and the cantilever spring can be twisted periodically.

[0006]

By forming the head at the free end of a cantilever spring having an excitation mechanism, the position of the head on the recording medium can be changed. By configuring the excitation mechanism by the piezo element built in the cantilever spring and the voltage applying device that applies a voltage to the piezo element, the head at the tip of the cantilever spring can be accurately vibrated.

By the exciting mechanism, the cantilever spring is periodically twisted in a state of approaching or in contact with the surface of the recording medium, whereby the data detection signal obtained from the probe can be modulated in the twisting period. . A tracking servo of the head position can be performed by the signal resulting from the modulation.

[0008]

FIG. 1 shows the structure of an embodiment of a cantilever spring having a head and a head at the tip according to the present invention. The cantilever spring 2 is provided with a head 1 at the center of its tip.
Is capable of detecting the atomic force between the medium and the head 1, the magnetic force, or the conductivity or permittivity of the medium. Also,
The cantilever spring 2 is formed with the piezoelectric elements 5 and 7 and the pattern electrode 6 substantially parallel to each other on the surface opposite to the surface having the head 1. One ends of the piezoelectric elements 5 and 7 are connected to one end of the pattern electrode 6. The other ends of the piezoelectric elements 5 and 7 and the pattern electrode 6 are provided with connecting electrodes 8, 10 and 9 on the base of the cantilever spring 2. These piezo elements 5 and 7 have a function of vibrating the cantilever spring 2 by a voltage applied via the connecting electrodes 8, 10 and 9.

The cantilever spring 2 has a two-layer structure, and the layer 4 is made of a conductive material. This layer 4 is electrically connected to the head 1 which is also conductive, and a signal from the head 1 can be taken out to the outside. The layer 3 is made of an insulating material and serves to electrically separate the piezoelectric elements 5 and 7 and the pattern electrode 6 from the conductive layer 4.

FIG. 2 shows a structure centering on a head driving portion of a recording apparatus using the head 1 and the cantilever spring 2 shown in FIG. It is fixed to the piezo element 11 via the base spacer 12 of the cantilever spring 2. AC power sources 16 and 17 are connected to the piezo elements 5 and 7 via electrodes 8 and 10, resistors 13 and 14, and a switch 15. AC power supply 16, 1
No. 7 has the same frequency with a phase difference of 180 degrees. By turning on the switch 15, an alternating voltage of opposite phase is applied to the piezo elements 5 and 7, and the cantilever spring 2 causes torsional vibration. Accordingly, the head 1 vibrates in the direction of arrow 50.

The recording medium has recording bits 21, 2
2 is recorded. The recording bits 21 and 22 are recorded due to changes in the shape of the recording medium, changes in conductivity, differences in magnetization direction, changes in dielectric constant, and the like. The head 1 has conductivity in order to detect these recording bits 21 and 22. In addition, when detecting the magnetization of the recording medium, the head 1 having conductivity and magnetism is used.

The recording bit 21 is a bit having a fixed length for detecting the tracking servo signal, and when the head 1 passes over the recording bit 21, the switch 15
It is designed to enter. When the switch 15 is turned on, the head 1 vibrates and the signal obtained by the recording bit 21 is modulated. This signal enables tracking tracking
BO signal can be obtained. This signal indicates whether the position of the head 1 is on the center of the recording bit 21 or on the left end.
It is obtained from the fact that the above modulation signal is different depending on whether it is at the right end. The modulated signal is applied as a tracking servo signal to the piezo element 11 holding the cantilever spring via the amplifier 18 and the piezo element driver 19.

When the head 1 is on a normal data bit, the signal from the head 1 is input to the data processing circuit 20 via the amplifier 18 as a data signal. The position of the head 1 on the recording medium is given by an upper control circuit (not shown).

In the above embodiment, the cantilever spring 2 has a two-layer structure and the surface on the side of the head 1 is made of a conductive material. However, the spring 2 is made of an insulating material. Needless to say, it may be a conductive film. The same applies to the head 1.

Although a specific example of the recording / reading method has not been described, it is needless to say that any method can be adopted for this, and the present invention is characterized by tracking. The description was omitted.

[0016]

According to the present invention, in the information recording apparatus, the head can be slightly vibrated on the medium, whereby the tracking servo signal can be obtained.

[Brief description of drawings]

FIG. 1 is a view showing a cantilever spring having a head.

FIG. 2 is a diagram showing a configuration of a recording apparatus using the head and the cantilever spring of FIG.

[Explanation of symbols]

1 ... Head, 2 ... Cantilever spring, 3 ... Insulating layer, 4 ... Conductive layer, 5 ... Piezo element, 6 ... Pattern electrode, 7 ... Piezo element, 8 ... Electrode, 9 ... Electrode, 10 ... Electrode, 11 ... Piezo element, 12 ... Spacer, 13 ... Resistor, 14 ... Resistor, 15 ...
Switch, 16 ... AC power supply, 17 ... AC power supply, 18 ... Amplifier, 19 ... Piezo element driver, 20 ... Data processing circuit, 21 ... Recording bit, 22 ... Recording bit, 50 ... Arrow.

Claims (3)

[Claims] 1. An information recording or reproducing apparatus comprising a disk-shaped recording medium and a recording or reproducing head arranged to face a recording track of the recording medium, wherein the head is formed at a free end of a cantilever spring. And an information recording or reproducing device, wherein the cantilever spring is vibrated at a predetermined position on a track. 2. The information recording according to claim 1, wherein the excitation mechanism of the cantilever spring comprises a piezo element built in the cantilever spring and a voltage application circuit for applying a voltage to the piezo element. Or playback device. 3. A detection signal obtained from the head is used by periodically twisting the cantilever spring using the piezo element in a state where the cantilever spring is close to or in contact with the surface of a recording medium. 2. An information recording or reproducing apparatus according to claim 1, wherein a tracking servo of the head position is performed by a recording head.