JP4149142B2 - Information recording / reproducing apparatus and method of coarse adjustment of information recording / reproducing apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an information recording / reproducing apparatus, such as a recording apparatus, a reproducing apparatus, and a recording / reproducing apparatus, using a flexible disk-shaped recording medium.
[0002]
[Prior art]
In conventional CD players, a rotary servo system that rotates the disk, a focusing servo system that maintains the laser beam waist near the disk recording surface, a seek servo system that moves the beam spot to the target track, and a beam spot It has a tracking servo system to make it follow.
[0003]
In this CD player, the disc is chucked, the disc is rotated immediately thereafter, laser light is emitted to the disc surface, and the objective lens repeatedly moves up and down to the maximum and minimum strokes, and the focus error and focus error signal Thus, a so-called S-shaped curve is generated, the beam waist of the laser beam is brought to the recording surface of the disk, and so-called focus pull-in operation is performed. That is, control is performed so that the recording surface of the disk falls within the focal depth of the objective lens from the S-shaped curve.
[0004]
[Problems to be solved by the invention]
However, since the stroke of the objective lens usually moves as large as about ± 0.5 mm, the actuator that drives the objective lens becomes heavy, the head mechanism is heavy, and the spring of the head mechanism cannot be strengthened, so the servo characteristics in the high frequency range are improved. It was difficult.
[0005]
That is, in a conventional CD player, the objective lens has a stroke of about 1 mm in the low frequency range during coarse adjustment for focus pull-in, and a stroke amount of about 500 μm in the high frequency range following the disc surface shake of about 500 μm during focusing. Since the spring is large and heavy and cannot be strengthened, the followability in the high frequency range cannot be improved. For this reason, it is difficult to cope with high-density recording on the disc.
[0006]
Therefore, the present invention provides an information recording / reproducing apparatus that enables high-density recording by reducing the movable distance of the objective lens and greatly improving the weight reduction of the head mechanism, high-frequency response, and the like. For that purpose.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, a first aspect of the present invention is a recording / reproducing apparatus using a flexible disk-shaped recording medium, wherein the disk-shaped recording medium is recorded and reproduced on one side of the disk-shaped recording medium. And a guide that is disposed on the other side of the disk-shaped recording medium and suppresses positional fluctuations such as surface deflection of the disk-shaped recording medium, and adjusts the amount of protrusion of the disk-shaped recording medium to the guide. An information recording / reproducing apparatus including a protrusion amount adjusting mechanism. In this configuration, the guide can suppress the deflection of the disk-shaped recording medium having flexibility, and the guide protrusion amount adjusting mechanism is provided. An information recording / reproducing apparatus capable of high-density recording can be provided by greatly improving the weight reduction, high-frequency response, and the like.
[0008]
Further, the invention according to claim 2 is the information recording / reproducing apparatus according to claim 1, wherein the protrusion amount adjusting mechanism is in a state in which a focus servo of an objective lens for condensing recording / reproducing light on the disk-shaped recording medium is locked. And a control means for determining the protrusion amount of the guide so that the direct current offset of the objective lens is minimized. In this configuration, the rough adjustment of the distance between the flexible disk-shaped recording medium and the objective lens is performed by adjusting the position of the flexible disk-shaped recording medium by adjusting the position of the flexible disk-shaped recording medium. The stroke in the focus direction can be reduced and the weight can be reduced. Therefore, the servo can be applied to a higher frequency range, and the characteristics of high linear velocity recording / reproduction can be improved.
[0009]
According to a third aspect of the present invention, there is provided the information recording / reproducing apparatus according to the first aspect, wherein the protrusion amount adjusting mechanism locks the focus servo of the objective lens that focuses the recording / reproducing light on the disc-shaped recording medium. And a control means for adjusting the height of the focus error signal by determining the S-curve of the focus error signal by coarsely adjusting the protrusion amount of the guide when the distance between the objective lens and the disk recording surface is roughly adjusted. Features. In this configuration, the rough adjustment of the distance between the flexible disk-shaped recording medium and the objective lens is performed by adjusting the position of the flexible disk-shaped recording medium by adjusting the position of the flexible disk-shaped recording medium. The stroke in the focus direction can be reduced and the weight can be reduced. Therefore, the servo can be applied to a higher frequency range, and the characteristics of high linear velocity recording / reproduction can be improved.
[0010]
According to a fourth aspect of the present invention, in the information recording / reproducing apparatus according to the first aspect, the guide is provided with a vibration sensor. In this configuration, if any abnormality occurs and a large surface shake occurs, abnormal vibration can be detected by the vibration sensor provided in the guide, so that the operation can be stopped immediately, the optical head is damaged, Media damage can be avoided.
[0011]
According to a fifth aspect of the present invention, in the information recording / reproducing apparatus according to the first aspect, a vibration sensor is provided on a spindle that rotates the disk-shaped recording medium. In this configuration, if some abnormality occurs and a large surface shake occurs, abnormal vibration can be detected by the vibration sensor provided on the spindle, so that the operation can be stopped immediately, the optical head is damaged, Media damage can be avoided.
[0012]
According to a sixth aspect of the present invention, in the information recording / reproducing apparatus according to the fourth or fifth aspect, when abnormal vibration is detected from the vibration sensor, the amount of protrusion of the guide is adjusted to reduce the abnormal vibration. And a control means for inputting a control signal to the protrusion amount adjusting mechanism. In this configuration, abnormal vibration is detected by the vibration sensor, and the amount of protrusion of the guide can be adjusted so as to reduce the abnormal vibration. Therefore, damage to the optical head and media can be avoided.
[0013]
According to a seventh aspect of the present invention, in the information recording / reproducing apparatus according to the sixth aspect, when an abnormal vibration larger than the abnormal vibration is detected from the vibration sensor, the guide is pulled in to retract the optical head and stop the spindle. It is characterized by having a control means to do. In this configuration, if any abnormality occurs and a large surface shake occurs, the vibration sensor can detect the abnormal vibration and stop the operation immediately, thus avoiding damage to the optical head and media. it can.
[0014]
The invention according to claim 8 is the information recording / reproducing apparatus according to any one of claims 1 to 7, wherein an electromagnet is provided in the guide. In this configuration, since the electromagnet is provided in the guide, it is not necessary to provide a new magnetic head in the magneto-optical information recording / reproducing apparatus.
[0015]
According to a ninth aspect of the present invention, there is provided a coarse adjustment of an information recording / reproducing apparatus for positioning a flexible disk-shaped recording medium and a head mechanism having an objective lens for condensing recording / reproducing light on the disk-shaped recording medium. In the method
With respect to a head mechanism that is disposed on one side of the disk-shaped recording medium and records / reproduces the disk-shaped recording medium, the surface of the disk-shaped recording medium is shaken by a guide disposed on the other side of the disk-shaped recording medium. To suppress the position fluctuation of
Next, in rough adjustment of the distance between the objective lens and the disk recording surface, instead of moving the objective lens, the protrusion amount of the guide is shaken to determine the S-curve of the focus error signal and to raise the height. This is a rough adjustment method for an information recording / reproducing apparatus. In this configuration, the rough adjustment of the distance between the flexible disk-shaped recording medium and the objective lens is performed by adjusting the position of the flexible disk-shaped recording medium by adjusting the position of the flexible disk-shaped recording medium. The stroke in the focus direction can be reduced and the weight can be reduced. Therefore, the servo can be applied to a higher frequency range, and the characteristics of high linear velocity recording / reproduction can be improved.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(Example 1)
FIG. 1 is a schematic configuration diagram of an information recording / reproducing apparatus according to a first embodiment of the present invention, and FIG. 2 is a diagram showing an outline of a guide periphery as viewed from the radial direction of the disk of the information recording / reproducing apparatus of FIG. FIG. 3 is a diagram showing an example of a cross-sectional structure of a flexible sheet-like recording disk that is recorded and reproduced by the information recording / reproducing apparatus of FIG. In FIG. 1 to FIG. 3, for convenience of explanation, the thickness of the sheet-like recording disk is shown enlarged from the actual.
[0017]
As shown in FIG. 1, an information recording / reproducing apparatus as an optical recording / reproducing apparatus includes a spindle 7a that holds a hub (not shown) of a sheet-like recording disk 1 that is a flexible disk-like recording medium, and a spindle 7a. The spindle motor 7 that rotates and the one side of the sheet-like recording disk 1, that is, the lower side in this embodiment, are focused on the TbFeCo magneto-optical recording layer 1 e that is the recording surface of the sheet-like recording disk 1. Then, the optical pickup 2 that is an optical head mechanism for recording and reproducing, the moving rail 3 that supports the optical pickup 2, and the other side of the sheet-like recording disk 1, that is, the upper side in the present embodiment, is arranged on the sheet-like recording disk 1 A guide 4 that suppresses positional fluctuations such as surface deflection and a guide that is a protrusion amount adjustment mechanism that adjusts the protrusion amount of the guide 4 with respect to the sheet-like recording disk 1. And an actuator 5. The illustration of the chuck hub bonded to the sheet-like recording disk 1 is omitted because it is similar to a known structure.
[0018]
The guide actuator 5 is attached to a chassis 6. In this embodiment, a piezo actuator is used as the guide actuator 5, but an electromagnetic actuator such as a linear motor may be used instead of the piezo actuator.
[0019]
As shown in FIG. 2, when the magneto-optical sheet recording disk 1 is used as in this embodiment, the guide 4 includes an electromagnet 4a for applying a magnetic field during recording / erasing. Yes. The electromagnet 4a can invert N and S of the TbFeCo magneto-optical recording layer 1e according to recording and erasing.
[0020]
As shown in FIG. 3, the sheet recording disk 1 is a magneto-optical sheet recording disk as described above. The cross-sectional structure of the sheet-like recording disk 1 is formed on the other surface of the base material 1b and the anti-sliding protective film 1a such as 200 nm thick DLC (diamond-like carbon) formed on one surface of the base material 1b made of a flexible sheet. Formed on the Ag reflective layer 1c, the SiNx protective layer 1d formed on the Ag reflective layer 1c, the TbFeCo magneto-optical recording layer 1e, which is a recording film formed on the SiNx protective layer 1d, and the TbFeCo magneto-optical recording layer 1e. The SiNx protective layer 1f and a transparent protective layer 1g made of an ultraviolet curable resin having a thickness of 5 μm or the like are used.
[0021]
The base material 1b of the sheet-like recording disk 1 is a dry photopolymer sheet having a thickness of 0.1 mm. A stamper with pits and grooves engraved on it is pressed and then peeled off by irradiating with ultraviolet rays. Form. Thereafter, the outer periphery was punched out into a circular shape with a diameter of 120 mm to form a disk. Furthermore, the inside was also punched out to a diameter of 10 mm.
[0022]
The thickness of the substrate 1b depends on the material used, but if it is too thick, the flexibility is lost and the position of the guide 4 cannot be defined. On the other hand, if it is too thin, the sheet-like recording disk 1 is destroyed without being able to withstand the acceleration / deceleration stress during rotation. The optimum value is generally in the range of 0.01 to 1.5 mm. Preferably it is 0.03-0.2 mm.
[0023]
A recording film is formed on the substrate 1b by sputtering. First, the Ag reflection layer 1c is formed with a thickness of 50 nm, the SiNx protective layer 1d is formed thereon with a thickness of 8 nm, and the TbFeCo magneto-optical recording layer 1e is formed thereon with a thickness of 15 nm. A SiNx protective layer 1f was formed thereon with a thickness of 40 nm. Note that x in SiNx is arbitrary. That is, since it deviates from the stoichiometric composition depending on the film forming conditions, it is expressed as x.
[0024]
In the case of the magneto-optical type, since a magnetic field is required at the time of recording, an electromagnet 4a is placed in the guide 4. The magneto-optical type has a smaller signal intensity than the phase change type and is strongly influenced by the polarization noise of the plastic substrate. However, in the present invention, this problem does not occur because the recording / reproduction is performed without passing through the substrate 1b. Note that a permanent magnet may be placed in the guide 4 and a drive mechanism for the permanent magnet may be inserted to invert N and S. However, it is preferable to insert the electromagnet 4a because the structure is simple.
[0025]
In addition, the recording density needs to be lowered a little because the signal is a little smaller, but the recording speed is magnetic recording, which is extremely fast. For this reason, a magneto-optical recording layer was used in this example. This recording layer can record at a linear velocity of 1 m / s or 30 m / s. Therefore, the sheet-like recording disk 1 could always be used at 15 m / s or more, which can be floated by an air flow.
An ultraviolet curable resin was spin-coated on the SiNx protective layer 1f and cured to form a transparent protective layer 1g having a thickness of 5 μm.
Finally, a hub for chucking was bonded to the center to obtain a flexible optical disk as the sheet-like recording disk 1.
A 20 nm thick DLC (diamond-like carbon) film was formed on the sliding surface of the sheet-like recording disk 1 with the guide 4 by sputtering.
[0026]
As described above, recording / reproduction is not performed by transmitting light through the sheet as the substrate 1b, but is performed through the transparent protective layer 1g, which is an ultraviolet curable resin. Therefore, an opaque material can be used as the substrate 1b.
[0027]
The optical recording / reproducing apparatus uses a semiconductor laser (not shown) having a wavelength of 405 nm, and uses an optical pickup 2 that collects light with an objective lens 2a having an NA of 0.85. The distance between the recording film of the sheet-like recording disk 1 and the objective lens 2a is about 0.2 mm.
[0028]
The sheet-shaped recording disk 1 is chucked by the spindle 7a, and a metal guide 4 is provided at a position opposite to the position of the objective lens 2a with the sheet-shaped recording disk 1 interposed therebetween. Since the sheet-like recording disk 1 is soft, the edge is slightly lowered by gravity, and nothing is touched immediately after chucking.
[0029]
When the sheet-like recording disk 1 rotates and reaches a specified rotation, it is substantially flattened by centrifugal force and comes into contact with the guide 4. However, they are not completely in contact with each other by the air flow between the sheet recording disk 1 and the guide 4. Thereafter, the optical pickup 2 approaches the sheet recording disk 1 and performs recording and reproduction. If the linear velocity is about 5 m / s, the air is completely lifted. However, positioning of the sheet-like recording disk 1 can be performed even in a rotation region where the air does not float.
[0030]
Since the guide 4 has a length equal to or longer than the moving distance of the optical pickup 2, for example, about the radius of the sheet-like recording disk 1, the optical pickup 2 and the guide 4 are always in an opposing position. Since the position of the sheet-like recording disk 1 in the focusing direction is defined by the guide 4, there is almost no blurring of the sheet-like recording disk 1 compared to a normal optical disk. Therefore, the movable distance of the objective lens 2a can be designed to be small. That is, it was greatly reduced from about ± 0.5 mm to about ± 0.05 mm. As a result, the actuator of the objective lens 2a is lightened, and the servo characteristics in the high frequency region are improved. This contributed to the expansion of the linear velocity margin of the optical pickup 2 when the linear velocity was increased. The length of the guide 4 can be shorter than the moving distance of the optical pickup 2.
[0031]
Although not shown, the sheet-like recording disk 1 is usually stored in a cartridge. When inserted into the drive, it is pulled out of the cartridge and chucked.
[0032]
Further, the shape of the guide 4 for positioning the sheet-like recording disk 1 is curved so that the tip thereof is hard to damage the sheet-like recording disk 1. The material of the guide was made of Ti alloy. The surface of the guide 4 was processed so as to have an unevenness of about 5 μm. This processing is for preventing sticking between the guide 4 and the sheet-like recording disk 1.
[0033]
As shown in FIG. 2, the guide 4 contains an electromagnet 4a for recording and erasing. By this electromagnet 4a, N and S can be reversed according to recording and erasing.
Both ends of the guide 4 are fixed to the chassis 6 via guide actuators 5 that are piezo actuators.
[0034]
The protrusion amount of the guide 4 is adjusted by a guide actuator 5 which is a fine movement mechanism of the guide 4. The adjustment of the protrusion amount is performed so that the focus offset of the objective lens 2a is small, for example, zero.
Further, the abnormal vibration of the guide 4 is detected by monitoring the impedance of the guide actuator 5.
[0035]
While the rotation of the sheet-like recording disk 1 is low, vibration due to sliding occurs, and the amplitude of the vibration decreases as the flying occurs. At this time, if vibration with an abnormally large amplitude is detected, the guide 4 is immediately pulled in, the optical pickup 2 as an optical head is also retracted, the spindle 7a is stopped, and the sheet-like recording disk 1 is returned to the cartridge to perform an ejecting operation. To do.
[0036]
Abnormal vibration refers to vibration generated in the sheet-like recording disk 1 during rotation due to variations in temperature, humidity, substrate thickness, etc., and extremely large abnormal vibration refers to the sheet-like recording disk 1 and the objective lens 2a. This is the vibration at the beginning of the collision.
[0037]
FIG. 4 is a block diagram of the servo control system excluding the signal processing system of the information recording / reproducing apparatus of FIG.
The servo control system of this information recording / reproducing apparatus is almost the same as that of a general optical disk drive, but the part for positioning the guide 4 with reference to the focus offset, the vibration data from the guide 4 is determined, and the operation of the drive The part to stop is added.
[0038]
This servo control system inputs a focus error signal and performs focusing when irradiating the recording surface of the sheet-like recording disk 1 with a focus servo, and a tracking error signal, and the laser beam is fed into the sheet. A tracking servo 9 for driving the slide motor 10 so as to follow the track of the recording disk 1; a spindle servo 12 for controlling the rotational speed or linear velocity of the sheet-like recording disk 1 by PLL control or the like; and a focus error signal And a guide servo 11 for driving the guide 4 so that the recording surface of the sheet-like recording disk 1 falls within the focal depth of the objective lens 2a, and a focus error signal is input to the focus servo 8 and the guide servo 11. Input tracking error signal to tracking servo 9 A preamplifier matrix 13, and a CPU14 which controls the entire apparatus. During the rotation of the sheet recording disk 1, the guide 4 basically stops after the height adjustment. Guide protrusion is used to remove the offset in the focus direction, and dynamic surface blur tracking is performed by the operation of the focus servo 8 of the objective lens 2a.
[0039]
The focus servo 8 constitutes a focus servo system together with the optical pickup 2, and on the basis of the focus error signal input from the preamplifier matrix 13, the recording surface of the sheet-like recording disk 1 and the objective lens 2a are applied to the actuator of the optical pickup 2. A control signal for driving the optical pickup 2 is input so as to keep the distance to the constant.
[0040]
The tracking servo 9 constitutes a tracking servo system together with the optical pickup 2 and the slide motor 10, and a laser beam is applied to the slide motor 10 on the track of the sheet-like recording disk 1 based on the tracking error signal input from the preamplifier matrix 13. A control signal for driving the optical pickup 2 is input so as to follow.
[0041]
Instead of moving the objective lens 2a so that the recording surface of the sheet-like recording disk 1 falls within the depth of focus of the objective lens 2a, the guide servo 11 does not move the objective lens 2a but guides the sheet-like recording disk 1 without moving. , The guide 4 is moved based on the focus error signal input from the preamplifier matrix 13 so that the DC offset is minimized, and the recording surface of the sheet-like recording disk 1 is the focal depth of the objective lens 2a. I try to get inside.
[0042]
The first specified position is the position of the guide (inclination and protrusion amount of the guide) where the reference disk stably floats with respect to the guide when a reference disk, which is a design reference sheet disk, is used. In FIG. 4, a virtual line schematically shows a position slightly below the horizontal position of the sheet-like recording disk 1 that is a flexible disk. That is, since the state in which the guide 4 pushes the sheet-like recording disk 1 slightly is stable, it is a position slightly below the sheet-like recording disk 1 in the horizontal position shown in FIG. At this time, the sheet-like recording disk 1 is bent like an inverted bowl.
[0043]
The spindle servo 12, together with the spindle motor 7 and the guide actuator 5, constitutes a spindle servo system. Based on a control signal input from the CPU 14, the rotational speed or linear speed of the sheet-like recording disk 1 is made constant by PLL control or the like. To control.
[0044]
The preamplifier matrix 13 receives reflected light from the recording surface of the sheet-like recording disk 1 by the optical pickup 2 and generates a focus error signal and a tracking error signal from the electrical signal photoelectrically converted.
[0045]
The CPU 14 monitors a control signal for controlling the rotational speed or linear velocity of the sheet-like recording disk 1 at a constant level and an actuator of the guide 4 and detects vibration with an abnormally large amplitude exceeding a standard amplitude value. In addition, a protrusion amount adjustment signal of the guide 4 is input to the guide servo 11, and further, when a vibration having an extremely large amplitude exceeding the specified value is detected, a control signal for guide pull-in is input to the guide actuator 5. An optical pickup retraction control signal is input to the actuator of the optical pickup 2 and the slide motor 10, and a stop signal is input to the spindle motor 7.
[0046]
Instead of moving the objective lens 2a so that the recording surface of the sheet-like recording disk 1 is within the focal depth of the objective lens 2a, the objective lens 2a is not moved, but the sheet-like recording disk 1 is moved in the optical axis direction by the guide 4 Then, the reflected light from the disk recording surface is received by the optical pickup 2 again, a focus error signal is generated by the preamplifier matrix 13, and the guide 4 is moved by the guide servo 11 so that the DC offset is minimized from the focus error signal. It moves so that the recording surface of the sheet-like recording disk 1 falls within the depth of focus of the objective lens 2a.
[0047]
Instead of moving the objective lens 2a so that the recording surface of the sheet-like recording disk 1 falls within the depth of focus of the objective lens 2a, the CPU 14 moves the sheet-like recording disk 1 with the guide 4 without moving the objective lens 2a. The reflected light from the disk recording surface is received by the optical pickup 2 and a focus error signal is generated by the preamplifier matrix 13. This focus error signal is input to the guide servo 11, and the sheet shape is obtained from the S-curve of the focus error signal. Control is performed so that the recording surface of the recording disk 1 falls within the focal depth of the objective lens 2a.
[0048]
When detecting abnormal vibration from the vibration sensor, the CPU 14 controls the guide actuator 5 to input a control signal for adjusting the protrusion amount of the guide 4 to reduce the abnormal vibration.
[0049]
When the CPU 14 detects an abnormal vibration larger than the abnormal vibration from the vibration sensor, the CPU 14 pulls in the guide 4 to retract the optical pickup 2 and controls the spindle 7a to stop.
The abnormal vibration larger than the abnormal vibration is a suddenly large pulse generated when the sheet-like recording disk and the guide come into contact with each other. For example, the amplitude peak value of the abnormal vibration of 5 Hz or more is in a stable state. This is the case when it exceeds the double.
[0050]
Further, the CPU 14 is arranged in a sheet form by a guide 4 disposed on the other side of the sheet recording disk 1 with respect to the optical pickup 2 disposed on one side of the sheet recording disk 1 and recording / reproducing the sheet recording disk 1. Before the focus servo of the objective lens 2a for condensing the recording / reproducing light on the sheet-like recording disk 1 is locked, the distance between the objective lens 2a and the disk recording surface is suppressed. At the time of rough adjustment, instead of moving the objective lens 2a, the protrusion amount of the guide 4 is swung to determine the S-curve of the focus error signal and to control the height.
[0051]
When the sheet-like recording disk 1 accommodated in the disk cartridge is inserted into the drive, it is chucked by the spindle 7a and rotated to a specified rotation.
Next, the guide 4 approaches the sheet-like recording disk 1 to the first specified position. This is a position where the sheet-like recording disk 1 serving as a reference can almost float. Here, the optical pickup 2 moves to the directory management area of the sheet-like recording disk 1.
[0052]
First, with the focus servo turned off, the protrusion of the guide 4 is finely adjusted to produce a so-called S curve, and then the focus servo is turned on.
In general, the S-curve gives a DC offset to the objective lens to adjust the height position. In the case of the present invention, the height adjustment is performed by the protruding amount of the guide 4. In principle, the objective lens 2a operates without a DC offset. Further, since the guide 4 removes a large surface shake of the sheet-like recording disk 1, the actuator of the objective lens 2a does not need to have a large amount of movement and can be reduced in weight.
[0053]
Next, the tracking servo 9 enters. Thereafter, the optical pickup 2 moves to the inner and outer peripheries according to the data reading, but the protruding amount of the guide 4 is controlled by the guide actuator 5 so that the DC offset of the focus servo 8 is always minimized. At this time, the abnormal vibration of the guide 4 is always monitored. When the standard value is exceeded, the protrusion amount of the guide 4 is finely adjusted. When the specified value is exceeded, the guide 4 is immediately pulled in, the optical pickup 2 is retracted, and the spindle 7a is stopped.
[0054]
Signals were recorded and reproduced by the sheet-like recording disk 1 and the information recording / reproducing apparatus.
Random 1-7 modulated by land & groove recording with recording peak power 4mW, erasing power 3.5mW, reproduction power 0.2mW, channel clock 100mHz, re-short mark length 0.15μm / bit, track pitch 0.32μm Data was recorded and played back. This corresponds to a capacity of 18 GB. Also, the recording rate was fast.
[0055]
The magneto-optical type forms a recording mark with a temperature distribution, so that a very fine multi-pulse strategy is unnecessary. For this reason, recording can be performed with a reduced number of pulse divisions as compared with a general multi-pulse used in CD-RW or the like.
For this reason, it is not necessary to increase the channel clock for the recording data rate.
[0056]
Recording and reproduction were possible under the same conditions from a radius of 25 mm to 58 mm. If the sheet-like recording disk 1 is a rigid body like a normal optical disk, the objective lens 2a collides with the disc surface shake and an error occurs. However, in the present embodiment, such a problem does not occur. .
[0057]
The sheet-like recording disk 1 and the guide 4 come into contact with each other for a moment when the sheet-like recording disk 1 is in a free state and is in an up-and-down vibration state (vibration of about ± 0.5 mm) before it becomes stable. there is a possibility. As the guide 4 is brought closer, the guide 4 and the sheet-like recording disk 1 approach each other, so that the air force comes out stably and does not come into contact. In order to perform recording / reproduction, the distance between the objective lens 2a of the optical pickup 2 and the recording film approaches about 0.1 to 0.2 mm. For this reason, the guide 4 is protruded so that the optical pickup 2 comes out when the sheet-like recording disk 1 is stabilized. The optical pickup 2 has to move greatly up and down only at the beginning. That is, the objective lens 2a of the optical pickup 2 moves greatly when searching for a focus (film). At other times, if the sheet-like recording disk 1 is stabilized by the guide 4, there is no need to move greatly. If the optical pickup 2 can be prevented from moving greatly, the weight of the optical pickup 2 can be reduced. Thus, the optical pickup 2 enters after the sheet-like recording disk 1 is stabilized in order to reduce the weight of the optical pickup 2. The guide 4 is moved so that the optical pickup 2 does not have to move, and the operation of searching for the focal point is performed by the guide 4 instead of the movement of the objective lens 2a.
As a result, the stroke amount of the optical pickup 2 can be significantly reduced to about ± 50 to 60 μm in the present invention, compared with the stroke amount of the conventional optical pickup of about 1 mm.
[0058]
(Example 2)
Although it is the same as that of Example 1, the recording film of the sheet-like recording disk 1 was changed as follows.
Sputtering on the substrate 1b by Ag reflection layer 150nm, SiC protective layer 8nm, AgInSbTeGe phase change recording layer 10nm, ZnS-SiO ₂ A protective layer of 30 nm was formed.
[0059]
Signals were recorded and reproduced with this sheet-like recording disk and drive. Random 1-7 modulated by land & groove recording with recording peak power 5 mW, erasing power 2.7 mW, reproduction power 0.3 mW, channel clock 66 mHz, re-short mark length 0.13 μm / bit, track pitch 0.32 μm Data was recorded and played back. This corresponds to a capacity of 20 GB.
Recording and reproduction were possible under the same conditions from a radius of 25 mm to 58 mm. Since it is a phase change type, a magnetic head is no longer necessary. Direct overwriting was also possible.
[0060]
(Example 3)
FIG. 5 is a block diagram showing a modification of the servo control system of FIG.
Although it is substantially the same as Example 1, the vibration sensor 15 is attached to the guide 4. When abnormal vibration occurs, the abnormality of the sheet-like recording disk 1 is transmitted to the guide 4, so that the abnormality can also be determined by vibration detection by the vibration sensor 15 provided on the guide 4.
[0061]
Example 4
FIG. 6 is a block diagram showing another modification of the servo control system of FIG.
Although it is substantially the same as Example 1, the vibration sensor 16 was attached to the bearing of the spindle 7a. When abnormal vibration occurs, the abnormality of the sheet-like recording disk 1 is also transmitted to the spindle 7a, so that the vibration detection from the vibration sensor 16 provided on the spindle 7a is also abnormal, as in the case where the vibration sensor is provided on the guide 4. Can be determined.
[0062]
As described above, according to the present invention, even in a high recording density optical recording system using an optical head with a high tilt NA and a narrow defocus margin and a high NA, the verticality of the spindle and flexibility This eliminates the need for consideration of surface wobbling of disc-shaped recording media. For this reason, a high-density optical disk system could be produced and used at low cost.
[0063]
Further, since there is a guide actuator 5 which is a fine adjustment mechanism of the guide 4, high accuracy is not necessary for the guide mounting accuracy.
Also, the guide actuator 5 is attached to the guide 4 and the protrusion amount is adjusted so that the focus offset of the objective lens 2a is small, so that the objective lens 2a is always a surface only in a relatively high frequency region near the middle point of the actuator. Just follow the shake. Therefore, the stroke of the actuator of the objective lens 2a can be designed small. Further, accuracy is not required for the chucking operation of the guide 4 or the sheet-like recording disk 1. This is because the guide itself can search for the optimum position within a certain range.
[0064]
If abnormal vibration occurs in the sheet-like recording disk 1 during rotation due to variations in temperature, humidity, substrate thickness, etc., it is detected as abnormal vibration in the guide 4 or the spindle 7a. In such a case, in the case of the objective lens 2a having a small working distance that cannot reduce surface blur, the sheet-like recording disk 1 and the objective lens 2a may collide, but there is a mechanism for detecting extreme abnormal vibration. As a result, the optical pickup 2 and the sheet-like recording disk 1 can be protected from damage.
In addition, this invention is not limited to the said Example. For example, in the above-described embodiments, the case of a writable sheet-like recording disk has been described as a flexible disk-like recording medium. However, the present invention also applies to a ROM-type flexible disk-like recording medium that cannot be written. The invention can be easily applied. That is, various modifications can be made without departing from the scope of the present invention.
[0065]
【The invention's effect】
As described above, by finely adjusting the distance to the objective lens with the guide, the movable distance of the objective lens is reduced, and the weight of the head mechanism and the high frequency response are greatly improved. Density recording can be made possible.
Further, since abnormal vibration can be detected by the vibration sensor, damage to the optical head and media can be avoided.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram of an information recording / reproducing apparatus according to a first embodiment of the present invention.
2 is a diagram showing an outline of the periphery of a guide as viewed from the radial direction of the disk of the information recording / reproducing apparatus in FIG. 1. FIG.
3 is a diagram showing an example of a cross-sectional structure of a flexible sheet-like recording disk that is recorded and reproduced by the information recording / reproducing apparatus of FIG. 1. FIG.
4 is a block diagram of a servo control system excluding a signal processing system of the information recording / reproducing apparatus of FIG. 1. FIG.
FIG. 5 is a block diagram showing a modification of the servo control system of FIG. 4;
6 is a block diagram showing another modification of the servo control system of FIG. 4;
[Explanation of symbols]
1 Sheet-shaped recording disk (disk-shaped recording medium)
1b Base material
1e TbFeCo magneto-optical recording layer
2 Optical pickup (optical head mechanism)
2a Objective lens
4 Guide
4a Electromagnet
5 Guide actuator (projection adjustment mechanism)
7 Spindle motor
7a spindle
8 Focus servo
9 Tracking servo
10 Slide motor (slider)
11 Guide servo
12 Spindle servo
13 Preamplifier matrix
14 CPU
15 Vibration sensor
16 Vibration sensor

Claims (9)

In a recording / reproducing apparatus using a flexible disk-shaped recording medium, a head mechanism that is arranged on one side of the disk-shaped recording medium and records / reproduces the disk-shaped recording medium, and on the other side of the disk-shaped recording medium And a guide that suppresses positional fluctuations such as surface wobbling of the disk-shaped recording medium, and is provided with a protrusion amount adjusting mechanism that adjusts a protrusion amount with respect to the disk-shaped recording medium. Recording / playback device. The protrusion amount adjusting mechanism includes a control means for determining the protrusion amount of the guide so that the direct current offset of the objective lens is minimized while the focus servo of the objective lens for condensing the recording / reproducing light on the disk-shaped recording medium is locked. The information recording / reproducing apparatus according to claim 1, further comprising: The protrusion amount adjusting mechanism is configured to adjust the distance between the objective lens and the disk recording surface before the focus servo of the objective lens for focusing the recording / reproducing light on the disk-shaped recording medium is locked. 2. The information recording / reproducing apparatus according to claim 1, further comprising control means for determining the S-curve of the focus error signal by adjusting the amount of protrusion and for determining the height. The information recording / reproducing apparatus according to claim 1, wherein the guide is provided with a vibration sensor. The information recording / reproducing apparatus according to claim 1, wherein a vibration sensor is provided on a spindle that rotates the disk-shaped recording medium. And a control unit configured to input a control signal for adjusting the protruding amount of the guide so as to reduce the abnormal vibration when the abnormal vibration is detected from the vibration sensor. The information recording / reproducing apparatus according to claim 4 or 5. 7. The information recording / reproducing apparatus according to claim 6, further comprising control means for retracting the optical head and stopping the spindle when the abnormal vibration larger than the abnormal vibration is detected from the vibration sensor. apparatus. The information recording / reproducing apparatus according to claim 1, wherein an electromagnet is provided in the guide. In a coarse adjustment method of an information recording / reproducing apparatus for positioning a flexible disk-shaped recording medium and a head mechanism having an objective lens for condensing recording / reproducing light on the disk-shaped recording medium,
With respect to a head mechanism that is disposed on one side of the disk-shaped recording medium and records / reproduces the disk-shaped recording medium, the surface of the disk-shaped recording medium is shaken by a guide disposed on the other side of the disk-shaped recording medium. To suppress the position fluctuation of
Next, in rough adjustment of the distance between the objective lens and the disk recording surface, instead of moving the objective lens, the protrusion amount of the guide is shaken to determine the S-curve of the focus error signal and to raise the height. A rough adjustment method for an information recording / reproducing apparatus.

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