JP2003022651A - Optical disk drive, optical information recorder and optical information reproducing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make an optical disk recordable in a high density by surely suppressing a face wobbling of the optical disk with an aerodynamic force on the both sides of the sheet-shaped flexible optical disk. SOLUTION: When a first stabilizing guide member 7 is brought close to a rotating optical disk 1, a pressure rise occurs on a disk intrusion side in the first stabilizing guide member 7 on the basis of the Bernoulli's theorem, the optical disk 1 lounds to float, a gap subsequently narrows according to a convex shape of the first stabilizing guide member 7, a rate of flow is increased to reduce pressure, and the optical disk 1 gets closer to the first stabilizing guide member 7. Furthermore, a second stabilizing guide member 9 pushes the optical disk 1 toward the first stabilizing guide member 7 because the second stabilizing guide member 9 with a shape that increase the pressure of air flow over an optical pickup 4 is provided, and the face wobbling on the optical disk 1 is satisfactorily suppressed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disc driving device, an optical information recording device and an optical information reproducing device for rotationally driving an optical disc which is a flexible sheet-like optical information recording medium. Is.

[0002]

2. Description of the Related Art In recent years, optical discs have been required to record a large amount of digital data as the digitization of television broadcasting has started. Among the methods for increasing the density of optical discs, the basic method is to reduce the spot diameter of light used for recording / reproduction.

Therefore, it is effective to shorten the wavelength of light used for recording / reproducing and increase the numerical aperture NA of the objective lens. For the wavelength of light, see CD (comp
actdisk) uses near-infrared light of 780 nm, DVD (digital
A wavelength near 650 nm of red light is used in a versatile disk. Recently, a blue-violet semiconductor laser has been developed, and it is expected that laser light near 400 nm will be used in the future.

Regarding the objective lens, the objective lens for CD is N
Although it was less than A0.5, NA for DVD is about 0.6. In the future, NA will be increased by increasing the numerical aperture (NA).
It is required to be 0.7 or more. However, increasing the NA of the objective lens and shortening the wavelength of light also means that the influence of aberration is increased when the light is stopped down. Therefore, the margin for tilting the optical disc is reduced. In addition, since the depth of focus decreases as the NA increases, the focus servo accuracy must be increased.

Further, since the distance between the objective lens and the recording surface of the optical disk becomes small by using the objective lens having a high NA, the focus servo at the time of start must be made unless the surface deviation of the optical disk is kept small. The objective lens may collide with the optical disc immediately before the optical pickup is pulled in, which causes a failure of the pickup.

As a large-capacity optical disk having a short wavelength and a high NA, for example, O PLUS E (vol. 20 No. 2) is used.
As shown on page 183 of the above, a recording film is formed on a substrate as thick and as rigid as a CD, and recording / reproducing light is passed through the thin cover layer to reach the recording film without passing through the substrate. On the other hand, a system of recording / reproducing has been proposed.

Further, as described in JP-A-7-105657 and JP-A-10-308059, for example, a flexible optical disk is rotated on a stabilizing plate having a flat surface, and A method for stabilizing the face wobbling is known.

[0008]

However, in the above-mentioned conventional technique, when the substrate of the optical disk is formed of a rigid body, in order to reduce the surface runout and tilt of the rotating optical disk, it is necessary to perform extremely accurate molding and heat treatment. The recording film must be formed at a low temperature so as not to cause deformation. This prolongs the tact time associated with the optical disc manufacturing, and causes a cost increase.

Further, in a method of rotating a flexible optical disk on a stabilizing plate, as described in Japanese Patent Application Laid-Open No. 10-308059, when the optical disk and the stabilizing plate are rotated on a simple flat plate. Slide in contact with each other, which causes the optical disc to vibrate and generate high-frequency surface wobbling. This surface deviation is often applied to a frequency region where the mechanical focus servo cannot respond, and residual servo error cannot be sufficiently suppressed.

Further, when the optical disk and the objective lens slide due to surface wobbling, dust is generated, and the dust or the like causes an error. In particular, Japanese Patent Laid-Open No. 7-1
As described in Japanese Patent Laid-Open No. 056575, when the recording film is present on the stabilizing plate side, the recording film of the optical disc is damaged by sliding, which causes an error directly.

An object of the present invention is to solve the above-mentioned conventional problems, and when recording / reproducing using a flexible sheet-shaped optical disk, a surface deviation of the optical disk is surely caused by aerodynamic force on both sides of the optical disk. Another object of the present invention is to provide an optical disc drive, an optical information recording device, and an optical information reproducing device that suppress the above and enable high-density recording.

[0012]

In order to achieve the above object, the invention according to claim 1 is such that a rotation driving means for rotating a flexible sheet-like optical disk and writing or reading on the optical disk are performed. An optical disk driving device comprising a stabilizing means for stabilizing the shake in the direction of the rotation axis at a portion by a pressure difference of an airflow based on Bernoulli's law, wherein the stabilizing means is installed on both sides of the optical disk. A sheet is provided with an area that does not cause a pressure difference in the air flow between the upstream side and the downstream side in the disc rotation direction of the portion of the optical disc where the surface deviation is stabilized by the stabilizing means. -Shaped optical discs are stabilized by providing "relief" parts in the front and back of the area where surface deviation is stabilized. The repulsive force of the optical disc at the part where it was made possible can be reduced, the effect of the stabilizing force due to the aerodynamic force is increased, and the aerodynamic force is further stabilized by installing the stabilizing members on both sides of the optical disc. Can be made to act in a direction that contributes to the conversion.

According to a second aspect of the present invention, in the optical disk drive apparatus according to the first aspect, the stabilizing means is provided on the recording surface side of the optical disk and on the surface opposite to the recording surface side. With this configuration, it is possible to effectively stabilize the shake in the rotation axis direction on the recording surface of the optical disc where writing or reading is performed.

According to a third aspect of the present invention, in the optical disk drive apparatus according to the first or second aspect, the stabilizing means installed on the recording surface side generates a repulsive force with respect to the optical disk. Since the repulsive force with respect to the suction force acting on the optical disk can be generated and the balance of the generated force can be adjusted, the surface wobbling can be further stabilized.

According to a fourth aspect of the present invention, in the optical disc drive apparatus according to the first, second or third aspect, the distance between the stabilizing means installed on the recording surface side and the optical disc is the side opposite to the recording surface side. It is characterized in that it is set longer than the distance between the stabilizing means installed on the optical disc and the optical disc. With this configuration, it is possible to prevent contact between the recording surface of the optical disc and the stabilizing means, and to prevent writing or reading errors. Can be prevented.

According to a fifth aspect of the present invention, in the optical disc drive apparatus according to any one of the first to fourth aspects, a stabilizing device is provided on the recording surface side of a portion of the optical disc where writing or reading is performed. The most projecting part of the means and the most projecting part of the stabilizing means installed on the side opposite to the recording surface are arranged so as to be displaced in the circumferential direction of the optical disk. By shifting the positional relationship between the two stabilizing means, the balance between the suction force and the repulsive force generated by the stabilizing means can be adjusted.

According to a sixth aspect of the present invention, there is provided a rotation driving means for rotating a flexible sheet-shaped optical disk, and an optical writing means for converging and writing information on the recording surface of the optical disk. An optical information recording apparatus comprising: a stabilizing unit that stabilizes a shake in the direction of the rotation axis in a region where writing is performed on an optical disc by the optical writing unit by a pressure difference of an air flow based on Bernoulli's law. Therefore, the stabilizing means is installed on both sides of the disk of the optical disk, and the pressure difference of the air flow is provided between the upstream side and the downstream side in the disk rotating direction of the part of the optical disk where the surface deviation is stabilized by both stabilizing means. A region that does not generate is provided, and by this configuration,
As a result of the effect of the invention described in (1), the state of the portion where writing is performed on the optical disk is stabilized, and the writing recording density can be increased.

According to a seventh aspect of the present invention, in the optical information recording apparatus according to the sixth aspect, the stabilizing means is installed on the recording surface side of the optical disk and on the side opposite to the recording surface. With this configuration, the same operational effect as that of the second aspect of the invention is achieved.

According to an eighth aspect of the present invention, in the optical information recording apparatus according to the sixth or seventh aspect, the stabilizing means installed on the recording surface side generates a repulsive force to the optical disc. With this configuration, the same operational effect as the invention according to claim 3 is achieved.

According to a ninth aspect of the present invention, in the optical information recording apparatus according to any one of the sixth to eighth aspects, the stabilizing means installed on the recording surface side is provided on the optical disc side of the optical writing means. This structure is fixed, and with this structure, the stabilizing means works well at a position close to the portion where the optical writing means writes on the optical disc, and the optical writing means moves further. If so, the stabilizing means can be moved together.

According to a tenth aspect of the present invention, in the optical information recording apparatus according to the ninth aspect, the facing installation distance with respect to the optical disc in the stabilizing means fixed above the optical writing means is set to the optical writing. The objective lens for condensing provided in the means is set to be shorter than the distance closest to the optical disc by the control operation. With this configuration, it is possible to improve the stability by the stabilizing means without being affected by the presence of the objective lens. An air flow can be generated.

The invention described in claim 11 is the invention according to claims 6 to 1.
0. In the optical information recording device according to any one of claims 1 to 5, the distance between the stabilizing means installed on the recording surface side and the optical disk is the distance between the stabilizing means installed on the side opposite to the recording surface and the optical disk. With this configuration, it is possible to prevent contact between the recording surface of the optical disc and the stabilizing means, and to prevent a write error.

The invention described in claim 12 is the invention according to claims 6 to 1.
1. In the optical information recording device as described in any one of 1 above, the most prominent part in the stabilizing means installed on the recording surface side with respect to the part where the optical writing means focuses light on the optical disc. 6. The stabilizing means installed on the side opposite to the recording surface is disposed so as to be offset from the circumferential direction of the optical disc, and the most projecting portion of the stabilizing means is disposed. The same effect as that of the invention can be obtained.

According to a thirteenth aspect of the present invention, there is provided a rotation driving means for rotating a flexible sheet-shaped optical disk,
Based on Bernoulli's law, an optical reading unit that focuses light on the recording surface of the optical disc and reads information by reflected light, and a shake in the rotation axis direction at a portion where the optical reading unit reads the optical disc An optical information reproducing apparatus comprising a stabilizing means for stabilizing by a pressure difference of an air flow, wherein the stabilizing means is installed on both sides of a disc of an optical disc, and the surface deviation is stabilized by both stabilizing means. A region that does not cause a pressure difference of the air flow is provided on the upstream side and the downstream side of the portion of the optical disc to be rotated in the disc rotation direction. With this configuration, the operation and effect of the invention according to claim 1 is achieved. hand,
The state of the portion of the optical disc where the reading is performed is stable, and the reading accuracy can be improved.

According to a fourteenth aspect of the present invention, in the optical information reproducing apparatus according to the thirteenth aspect, the stabilizing means is installed on the recording surface side of the optical disk and on the side opposite to the recording surface. With this configuration, the same operational effect as that of the second aspect of the invention is achieved.

According to a fifteenth aspect of the present invention, in the optical information reproducing apparatus according to the thirteenth or fourteenth aspect, the repulsive force is generated on the optical disk by the stabilizing means installed on the recording surface side. And with this configuration,
The same operation and effect as the invention according to claim 3 are achieved.

The invention described in claim 16 is based on claims 13 to
15 In the optical information reproducing device described in any one of the above items,
The stabilizing means installed on the recording surface side is fixed to the optical disc side of the optical reading means, and the stabilizing means is preferably provided at a position close to a portion where the optical reading means reads the optical disc. If the optical reading means moves, the stabilizing means can move together.

According to a seventeenth aspect of the present invention, in the optical information reproducing apparatus according to the sixteenth aspect, the facing installation distance to the optical disc in the stabilizing means fixed above the optical reading means is set to the optical reading means. The objective lens for condensing provided is set to be shorter than the distance closest to the optical disc by the control operation, and with this configuration, the same operation and effect as the invention according to claim 10 is obtained.

The invention described in claim 18 is based on claims 13 to
17. In the optical information reproducing device described in any one of 17,
The distance between the stabilizing means installed on the recording surface side and the optical disk is set to be longer than the distance between the stabilizing means installed on the side opposite to the recording surface and the optical disk. The same effect as that of the invention described in claim 11 is obtained.

The invention as defined in claim 19 is based on claim 13 to
18. In the optical information reproducing apparatus according to any one of 18 above,
With respect to the portion where the optical reading means collects light on the optical disc, the most protruding portion of the stabilizing means installed on the recording surface side and the stabilizing means installed on the opposite surface side of the recording surface. The most prominent portion of the optical disc is arranged so as to be displaced in the circumferential direction of the optical disc, and with this configuration, the same operational effect as the invention according to claim 5 is obtained.

[0031]

BEST MODE FOR CARRYING OUT THE INVENTION Preferred embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic block diagram of an optical information recording / reproducing apparatus for explaining the first embodiment of the present invention.
Is a flexible sheet-shaped optical disc, 2 is a spindle shaft for holding the hub 1a of the optical disc 1, 3 is a spindle motor for rotationally driving the spindle shaft 2,
Reference numeral 4 denotes an optical pickup as a recording means for writing information on the optical disc 1 and a reproducing means for reading the written information, and 5 condenses light from a light source (not shown) on the optical disc 1. And optical disc 1
The objective lens provided in the optical pickup 4 so that the reflected light from the optical disk 4 passes, 6 is a pickup positioning device for moving the optical pickup 4 in the radial direction of the optical disc 1, and 7 is the optical pickup 4 via the optical disc 1. The first stabilizing guide member 8 is provided so as to face the first stabilizing guide member 7 for preventing surface deviation of the optical disc 1, and the first stabilizing guide member 7 is a stabilizer for moving the first stabilizing guide member 7 in the radial direction of the optical disc 1 in cooperation with the optical pickup 4. The guide positioning device 9 is fixed to the upper part of the optical pickup 4 and is formed with a through hole 9a for opening the light incident / emission surface portion of the objective lens 5,
Along with the first stabilizing guide member 7, a second stabilizing guide member 10 for preventing surface wobbling of the optical disc 1 is an apparatus main body for accommodating the above-mentioned respective constituent members.

FIGS. 2 (a) and 2 (b) are explanatory views of the recording means and the reproducing means constituting the optical pickup. As the recording means, as shown in FIG. 2 (a), the input recording signal is input. From the laser drive control circuit 12, a signal processing circuit 11 that performs digital signal conversion processing, signal compression processing, and the like, a laser drive control circuit 12 that generates a laser drive control signal based on the output from the signal processing circuit 11, The laser light source 1 includes a laser drive unit 13 for driving a laser light source 14 including a semiconductor laser and the like.
Emitted light La of high emission energy emitted from 4 is condensed by the objective lens 5 of the optical pickup 4 shown in FIG. 1 and irradiates the recording surface of the optical disc 1 as a light spot, and information recording is performed by bit formation.

As shown in FIG. 2B, the reproducing means is composed of a photoelectric conversion element 17 such as a photodiode and a reproduction signal processing circuit 18, and is formed on the recording surface of the optical disc 1. Laser light of low emission energy is emitted from the laser light source 14 to the bit,
The reflected light Lb passes through the objective lens 5 and the photoelectric conversion element 1
The light is received at 7, and the reproduction signal processing circuit 18 performs signal expansion processing on the output from the photoelectric conversion element 17 to generate a reproduction signal.

The optical disc 1 has a structure as shown in the sectional view of FIG. 3, and the recording layer 20 faces the objective lens 5 of the optical pickup 4, and the substrate 21 faces the first stabilizing guide member 8. As described above, the chucking portion provided on the spindle shaft 2 is set.

A specific example of the optical disc 1 in this embodiment will be described. 0.1 to give flexibility as a substrate
A thin sheet of about mm was used. For example, a groove having a stamper pitch of 0.6 μm and a width of 0.3 μm is transferred by thermal transfer to a sheet of polyethylene terephthalate having a thickness of 80 μm, and then the sheet / Ag reflective layer is sputtered to 120 nm / (ZrO ₂ —Y ₂ O ₃ ) -SiO ₂ , 7nm
/ AgInSbTeGe, 10 nm / ZnS-SiO ₂ ,
Film formation was performed in the order of 80 nm / Si ₃ N ₄ 40 nm. This sheet is spin-coated with UV resin and cured by ultraviolet irradiation to form a transparent protective film with a thickness of 5 μm. Further, the disc is melted and crystallized with a laser beam having a large diameter to obtain the reflectance. I used a raised one.

The stabilization of the surface deviation of the flexible sheet-shaped optical disk in this embodiment will be described with reference to the explanatory view of FIG. At the time of recording / reproducing, the flexible optical disc 1 having the above configuration is rotated between the optical pickup 4 and the second stabilizing guide member 9 and the first stabilizing guide member 7. The rotating optical disk 1 itself has a small amount of rigidity, and has a force that, when rotated, tends to be in a straight state by the action of centrifugal force.

As shown in FIG. 4, a second stabilizing guide member 9 is provided above the optical pickup 4 closer to the optical disc 1 than the objective lens 5. When the optical disc 1 rotates, an air flow is generated. When the first stabilizing guide member 7 is brought closer to the optical disc 1, pressure rises on the disc intrusion side of the first stabilizing guide member 7 based on Bernoulli's law, the optical disc 1 repels and floats,
After that, since the gap is narrowed according to the convex shape of the first stabilizing guide member 7, the flow velocity is increased and the pressure is reduced,
The optical disc 1 approaches the first stabilizing guide member 7.

Further, in the present embodiment, as shown in FIG. 4, since the optical pickup 4 is provided with the second stabilizing guide member 9 having a shape for increasing the pressure of the air flow, the second stabilizing guide member 9 is an optical disc. 1 for the first stabilizing guide member 7
The state is such that the optical disc 1 is pushed toward, and the surface wobbling on the optical disc 1 is suppressed more favorably. As a result, large surface wobbling (runout in the disc rotation axis direction) can be reduced.

In the present embodiment, the first stabilizing guide member 7 is placed opposite to the substrate 21 of the optical disc 1, and
The stabilizing guide member 9 is installed only above the optical pickup 4. For example, in the configuration example of FIG. 4, as the first stabilizing guide member 7, a columnar one whose facing surface facing the optical disk 1 has an arc shape is used. Optical disc 1 by action
The point where the surface runout is stable is point A. Since the surface runout is minimized by the aerodynamic force in this portion A, strain due to bending occurs in the vicinity of the portion A. Therefore, regions (spaces without the first stabilizing guide member 7 and the second stabilizing guide member 9) B and C where the action of the air pressure is not generated are provided on the upstream side and the downstream side in the disc rotation direction,
The optical disc 1 is placed at the front and rear positions of the portion A where the surface shake is stabilized.
By providing a portion that becomes “escape”, the repulsive force of the optical disc 1 at the portion A where the surface deviation is stabilized is reduced.

As for the relationship between the pressures at the parts A, B and C in FIG. 4, it is necessary that the relationship Pb>Pa> Pc is established, where the pressures at the parts are Pa, Pb and Pc.

That is, by setting the relation of Pb> Pa, a force for separating the optical disc 1 from the first stabilizing guide member 7 is generated, and the optical disc 1 and the first stabilizing guide member 7 are brought into sliding contact with each other. To prevent abnormal vibration or dust. Further, since the optical disc 1 maintains a proper distance from the first stabilizing guide member 7 to stabilize the surface deviation, a force for pushing the optical disc 1 from the optical pickup 4 side to the first stabilizing guide member 7 is required. Therefore, P
It is necessary to establish the relationship of a> Pc.

The force for reducing the surface wobbling at the portion A is
First stabilizing guide member 7 whose position is physically fixed
In addition, it is the force by which the optical disk 1 is attracted by the air pressure (negative pressure). Specifically, the first stabilizing guide member 7
By pulling the optical disc 1 upward by the above, and the second stabilizing guide member 9 pushes the optical disc 1 from the lower side to the upper side, a force for pushing the optical disc 1 to the first stabilizing guide member 7 (which serves as a position reference) is generated. Further, it is possible to further increase and reduce the surface deviation in the optical disc 1. The force for pushing the optical disk 1 from the lower side to the upper side by the second stabilizing guide member 9 is air pressure (positive pressure) and becomes a repulsive force when viewed from the second stabilizing guide member 9.

Due to the relational structure of the respective parts as described above, the effect of the surface wobbling stabilizing force by the aerodynamic force on the optical disk 1 is increased.

If a negative pressure is generated in the second stabilizing guide member 9 and a suction force is generated on the optical disc 1, negative pressure is generated on both sides of the optical disc 1, and the first stabilizing guide is generated. The difference in pressure between the member 7 and the second stabilizing guide member 9 becomes small, the force for pressing the optical disc 1 against the first stabilizing guide member 7 decreases, and the force for suppressing surface wobbling on the optical disc 1 becomes small. Will end up.

In this embodiment, the first stabilizing guide member 7 is provided on the side of the substrate 21 which is the side opposite to the recording layer 20 of the optical disc 1, and is used for recording / reproducing with respect to the recording layer 20 of the optical disc 1. Recording / reproduction is performed by condensing the lights La and Lb. The first stabilizing guide member 7 stabilizes the substrate 21 side opposite to the recording layer 20. By this, by any chance,
Even if the first stabilizing guide member 7 and the optical disc 1 slide on each other, the recording layer 20 is not damaged and does not directly cause an error. Further, the optical disc 1 usually has a convex warp on the recording layer 20 side. This corresponds to that the sputtered film in the recording layer 20 has compressive stress. Therefore, when the first stabilizing guide member 7 is pressed against the substrate 21 side, the pressure bonding force between the first stabilizing guide member 7 and the optical disk 1 becomes more stable, and the surface runout is prevented. Good compression.

Further, since the recording / reproducing light La and Lb directly enter / exit the side of the optical disc 1 opposite to the portion A where the surface shake on the side of the recording layer 20 is stabilized,
Even if the optical disc 1 slides on the first stabilizing guide member 7 and is scratched, the scratch does not occur on the recording layer 20, and therefore a recording / reproducing error does not occur, and the optical disc is also prevented. Even if the substrate 21 of No. 1 is scratched, the recording / reproducing light La, Lb does not pass through the substrate 21, so
For example, the substrate 21 may be opaque without being affected by the scratches of No. 1 and the optical characteristics of the substrate 21.

The operation of the second stabilizing guide member 9 in this embodiment will be described. According to Bernoulli's law, the aerodynamic force for stabilization described above increases as the optical disk 1 and the stabilization guide members 7, 9 are closer to each other. For this reason,
The first stabilizing guide member 7 needs to be close to the optical disc 1. However, since the second stabilizing guide member 9 may have a so-called “subordinate” action of reducing surface wobbling by pushing the optical disc 1 toward the first stabilizing guide member 7, the second stabilizing guide member 9 is applied to the recording layer 20 of the optical disc 1. The surface of the first stabilizing guide member 7 and the optical disc 1 in order to prevent the occurrence of sliding scratches on the optical disc 1.
It is necessary that the distance between the second stabilizing guide member 9 and the surface of the recording layer of the disc 1 is longer than the distance between them.
Therefore, in this embodiment, the distance between the second stabilizing guide member 9 and the surface of the optical disc 1 is set longer than that of the first stabilizing guide member 7.

Further, since the second stabilizing guide member 9 is mainly configured to generate a repulsive force, the second stabilizing guide member 9 and the recording layer 20 of the optical disc 1 hardly collide with each other. . Further, since the second stabilizing guide member 9 is installed so as to protrude from the surface of the optical disc 1 beyond the installation position of the objective lens 5, the objective lens 5
The optical disc 1 does not directly collide with the objective lens 5, and the objective lens 5 is protected from the collision.

Second stabilizing guide member 9 and optical disk 1
The distance from the surface is set to be 50 μm to 150 μm. Both too close to each other are likely to slide. The surface deviation of the optical disk 1 is less than 10 μm, but since the surface deviation gradually increases toward the periphery of the stable point, it is desirable to set it to more than 10 μm and set to 50 μm with a margin. Further, since the control working distance of the objective lens 5 having a high NA is about 0.1 mm to 0.4 mm, the second stabilizing guide member 9 is more than the control working distance of the optical disc 1.
Must be installed on the side. From this, the distance between the second stabilizing guide member 9 and the surface of the optical disc 1 is 50 μm.
It is desirable to set it to be m to 150 μm.

A more specific description will be given with reference to the explanatory view of FIG. In FIG. 4, when the component other than the first stabilizing guide member 7 or the apparatus main body case or the optical disk 1 is used in a state of being housed in a cartridge, the cartridge does not operate according to Bernoulli's law. Optical disc 1 1m from them
It is assumed that they are separated by about m or more. However, exceptionally, when the objective lens 5 has a high NA, the working distance becomes short,
The objective lens 5 comes close to about 0.05 mm to 0.3 mm. Therefore, the second stabilizing guide member 9 approaches a distance of less than 0.2 mm. The distance between the second stabilizing guide member 9 and the closest contact point of the optical disc 1 is about 50 μm.
m to 150 μm.

Further, FIG. 5 shows the measurement result of the surface deviation of the optical disk in the configuration of FIG. The first stabilizing guide member 7 has a tip shape with a radius of 50 mm and a diameter of 20 mm, and the optical disk 1 has a recording film formed by forming a tracking groove having a pitch of 0.65 μm on a PET (polyethylene terephthalate) sheet of 80 μm. It is formed by sputtering and has a radius of 45 mm and a rotation speed of 200.
The surface runout in a stable state was measured using a laser displacement meter at 0 rpm.

Since there is no abnormal vibration in the first stabilizing guide member 7 and no sliding scratches have occurred on the optical disc 1, it is judged that excessive air levitation has not occurred and no sliding state has occurred. be able to. In addition, the disc surface deviation is about 2 μm, and a normal rigid disc is 50 μm.
It can be seen from the fact that the above-mentioned surface deviation occurs, it is extremely small.

Both stabilizing guide members 7, 9 of this embodiment
In any case, the above-mentioned favorable surface runout stabilization was obtained regardless of whether it was installed in the apparatus body case or inside the cartridge.

Recording and reproduction were performed on the disk system according to the present embodiment having the above structure using an optical pickup having a wavelength of 405 nm and NA of 0.9. For example, the recording position on the optical disc was a radius of 45 mm, the shortest recording bit length was 0.12 μm, and random digital data was modulated by 1-7 RLL and recorded.

The recording linear velocity is 10 m / s, the recording peak power is 5 mW, the erasing power is 2.6 mW, the recording bottom power is 0.1 mW, and the reproduction is 0.25 m.
When run at W, the jitter between the base clock and the recorded signal was less than 8%. Further, stable focusing and tracking were performed without disturbing the envelope of the recording signal. The residual focus error was measured for both recording and reproduction, but the defocus amount was ± 0.12 μm or less. At a high NA of 0.8 or more, the defocus margin is extremely narrow, and it is only a fraction of that of a DVD or the like, and it is essential to set the defocus amount to ± 0.2 μm or less. In that sense, it can be said that sufficient focus stabilization was performed in the present embodiment.

Further, the defocus was evaluated by reproducing by increasing the linear velocity to 20 m / s, and the amount was ± 0.12 μm or less as in the above. With conventional high-rigidity discs, when linear velocity is increased, surface wobbling increases due to effects such as resonance, and the surface wobbling cycle becomes faster according to the number of rotations, making it difficult to follow the focus servo. Good results were obtained compared to the increase in focus amount. This is because, in the present embodiment, since the aerodynamic stabilization is used, the stabilizing force increases as the linear velocity increases.

In this embodiment, in order to effectively obtain the aerodynamic stabilization, it is necessary to consider the operation timing of each member. The recording / reproducing operation in this embodiment will be described with reference to the flowchart shown in FIG.

That is, when a start signal is input to a central processing circuit (not shown), the spindle motor 4 is started to rotate the optical disc 1 (S1), and when a predetermined number of revolutions is reached (YES in S2). , The first stabilizing guide member 7 is moved to a predetermined approach position with respect to the optical disc 1 (S3). Here, when the surface displacement is measured by using a laser displacement meter or the like, and when the surface displacement is within a predetermined stable region (YES in S4), the optical pickup 4 is moved to a predetermined approach position with respect to the optical disc 1 (S5). ,
At this point, recording / reproduction is started (S6).

The first stabilizing guide member 7 is interlocked with the stabilizing guide positioning device 8 and the optical pickup 4 is interlocked with the pickup positioning device 6, so that the optical pickup 4 and the second stabilizing guide member 9 are interlocked. Then, the first stabilizing guide member 7 is moved in the radial direction of the optical disc 1 so as to face each other (S7), and the operation is continued until recording / reproduction of all signals is completed (S8).

The shape of the first stabilizing guide member 7 is basically the above-mentioned shape, but by forming it like the first stabilizing guide member 25 shown in FIG. I was able to stabilize the run-out. Figure 7
In the first stabilizing guide member 25 shown in FIG. 3, the positive pressure generating portion 25a having a convex shape is formed on the side where the optical disk 1 enters, and the positive pressure generating portion 25a compresses the positive pressure generating portion 25a by the rushing air to generate a pressure higher than the atmospheric pressure. Since the pressure increases, a repulsive force is generated between the first stabilizing guide member 25 and the optical disc 1. In addition, the optical disk 1 of the first stabilizing guide member 25
The negative pressure generating portion 25b having a concave shape is formed on the side from which the air is discharged, and the air flowing by the negative pressure generating portion 25b expands rapidly to a negative pressure compared to the atmospheric pressure. An attractive force is exerted between 25 and the optical disc 1.

As described above, the surface deviation of the optical disc 1 can be stabilized only by the balance between the attraction force and the repulsion force generated by the difference in air pressure according to Bernoulli's law between the first stabilizing guide member 25 and the optical disc 1. You can do it.

Further, by providing the flat portion 25c at the boundary (the guide surface curvature boundary line) between the positive pressure generating portion 25a and the negative pressure generating portion 25b in the first stabilizing guide member 25, the expansion of the stable surface blur area is achieved. I can take a large. As described above, both the repulsive force and the attraction force are generated in the first stabilizing guide member 25, and these acting forces act on the optical disc 1 and the first stabilizing guide member 2.
The distance to 5 can be stabilized.

The configuration of the second stabilizing guide member 9 may be similar to that of the first stabilizing guide members 7 and 25, and the first stabilizing guide members 7 and 25 are the objectives. There is a difference in that it is necessary to have a configuration that secures an optical path that does not hinder the incidence / emission of light from the light source in the lens 5.
For example, the second stabilizing guide member 9 may be provided with a through hole for entering / exiting light, or an optical component may be installed in the through hole, and further, the second stabilizing guide may be provided. It is conceivable to form the entire member 9 with an optical material that does not affect the incidence / emission of light from the objective lens 5.

The first and second stabilizing guide members 7,
As the material of 9, 25, it is desirable to use a material having excellent smoothness in which air smoothly flows on the surface and temperature resistance that can withstand high temperature, and a stainless material can be exemplified.

The first stabilizing guide members 7, 25
As shown in FIG. 8, it is conceivable that the stable state of the optical disc 1 adapted to the design and specifications of the optical disc 1 or the device is appropriately set by facing the optical disc 1 and being installed at a plurality of locations in the circumferential direction. .

In this embodiment, since the surface wobbling or the tilt is corrected by the aerodynamic force, the optical disk 1 inevitably has to be soft and flexible. As a result, in the area which is not stabilized by the stabilizing guide member, the optical disc 1 has a large surface deviation as compared with that of a normal disk material such as a CD, and the surface deviation up to about 0.5 mm is easy. Occur. In some cases, it is difficult for the light stabilizing guide member around the pickup 4 to converge the surface deviation to 5 μm or less at once.

Therefore, in the present embodiment, as shown in FIG. 8, a plurality of first stabilizing guide members 7 are provided in the circumferential direction of the optical disc 1 and at a position separated from the periphery of the optical pickup 4. By roughly stabilizing the entire optical disc 1 and further stabilizing it on the main stabilizing surface (in the vicinity of the optical pickup 4), it is possible to improve the margin of the device system design.

The first stabilizing guide member 7 provided for rough stabilization does not need to be so precise in the stabilizing action. Since it suffices to take a large surface deviation reaching about 0.5 mm, it is sufficient for the shape to mainly generate a repulsive force, and a simple spherical convex action is sufficient. Rather, it is necessary to have an installation configuration that does not cause sliding. This is because it is preferable that sliding does not cause unnecessary vibration. Therefore, the first stabilizing guide member 7 as an auxiliary guide for rough stabilization has a larger flying height than the first stabilizing guide member 7 as a main guide near the optical pickup 4. Is preferable because it is large. That is, the larger the guide shape, the larger the flying height tends to be.

For example, if the first stabilizing guide member 7 as a main guide is a cylinder having a diameter of 10 mm, and if the first stabilizing guide member 7 as an auxiliary guide has a larger diameter of 20 mm, the levitation amount is supplemented. The guide is bigger. By doing so, the frequency of occurrence of sliding could be reduced.

When the shape of the first stabilizing guide member 7 is a cylinder and the tip has a hemispherical shape,
There is a proportional relationship between the area of the cross section parallel to the optical disc 1 and the flying height. Therefore, if the auxiliary guide is large, the flying height is stable in a large area.

In the first embodiment shown in FIG. 1, the first stabilizing guide member 7 and the stabilizing guide positioning device 8 are installed in the upper part of the device body 10. Therefore, the user can handle the optical disc 1 in a bare state without the cartridge.

In this case, since the optical disc 1 is a single thin sheet, for example, by putting it in a bag for handling, taking it out when using it, and setting it on the spindle shaft 2 for use, inexpensive optical information can be obtained. It can be a recording medium.

FIG. 9 is a schematic configuration diagram of an optical information recording / reproducing apparatus for explaining the second embodiment of the present invention. The configuration of the second embodiment different from that of the first embodiment is one optical disc. 1 is built in a disc cartridge 27 provided with opening windows 26, 26, the disc cartridge 27 is set at a predetermined position in the apparatus, and shutters 28, 28 are moved by an operating means (not shown) to open the opening window. The point is that the first stabilizing guide member 7, the optical pickup 4 and the second stabilizing guide member 9 are moved so as to be inserted into 26 and 26 so that recording / reproducing is possible.

Since the disk cartridge 27 having a general structure can be adopted, the cost does not increase.

FIG. 10 is a schematic block diagram of an optical information recording / reproducing apparatus for explaining the third embodiment of the present invention.
In the third embodiment, the first stabilizing guide member 30 is installed inside the disc cartridge 31. In this case, as shown in FIG. 11, the first stabilizing guide member 30 has a horizontally elongated shape extending in the radial direction of the optical disc 1 and is positioned for stabilizing guide as in the first and second embodiments. The mechanism 8 is unnecessary. Due to the action of the first stabilizing guide member 30, the surface deviation stabilization of the optical disc 1 occurs in the same manner as described in the first embodiment, and by the first stabilizing guide member 30,
The first area is set so that the area where the surface deviation of the optical disc 1 can be stabilized is located at the converging point of the optical pickup 4.
The stabilization guide member 30 is installed.

In the third embodiment, the shutter 28 is moved by operating means (not shown) to open the opening window 26.
The second stabilizing guide member 9 and a part of the optical pickup 6 are moved so as to be inserted thereinto so that recording / reproducing is possible.

In the third embodiment, since the first stabilizing guide member 30 is built in the disk cartridge 31, the overall structure of the device is substantially the same as that of a conventional device using a rigid substrate optical disk. Therefore, compatibility with an optical disk system using such a rigid substrate can be easily achieved.

FIG. 12 is a plan view for explaining an embodiment of the disc cartridge according to the present invention, and FIG. 13 is FIG.
FIG. 9 is a partial cross-sectional view taken along the line AA in FIG. 4 and is a disc cartridge that can be used in a device similar to the optical recording / reproducing device of the first embodiment.

As shown in FIGS. 12 and 13, a plurality of flexible sheet-shaped optical discs 1 can be accommodated in the disc cartridge 33 and can be used as a changer. The capacity can be increased by the number of stored optical disks 1. Even if a large number of optical discs 1 are stored in the disc cartridge 33, the entire volume of the disc cartridge 33 does not increase because the optical disc 1 is thin.

The disk cartridge 33 of this embodiment
Has a structure in which one end of each optical disc 1 is sandwiched between disc trays 34 that support the optical disc 1 and stored in a stacked state.
4 is a recording / reproducing device and this disc cartridge 33
The changer operation is performed by moving in and out between.

The disc tray 34 is provided with a disc tray identifying portion 35 at a different position for each disc, and a changer mechanism (not shown) for detecting the different position and inserting / removing the disc tray is provided on the recording / reproducing apparatus side. By installing the optical discs, it is possible to separately insert and remove each optical disc.

In this embodiment, since the optical disc 1 is thin, the disc space is narrow. Therefore, in order that the changer mechanism of the recording / reproducing apparatus can distinguish the upper and lower optical discs 1 from each other, the disc tray identifying portions 35 are provided at different positions in the lateral direction in each disc tray 34, as shown in FIG. It is installed. On the recording / reproducing apparatus side, the disc tray identification units 35 located at different positions in the lateral direction.
The optical disc 1 can be taken in and out of the disc cartridge 33 by, for example, hooking an arm member (not shown) in the hole 35a formed in the disc tray identifying portion 35 and moving the arm member. Compared to the configuration in which the disc tray identifying unit 35 is installed vertically, in the configuration according to the present embodiment, the distance in the lateral direction is relatively large, so that identification can be performed easily.

As described above, since the disc cartridge 33 shown in FIGS. 12 and 13 has a structure in which the disc trays 34 are simply overlapped with each other, it has an extremely simple structure and can be made into a compact and large-capacity cartridge.

Although the rewritable type optical disk using the phase change recording layer has been described in the above description of the embodiment, the present invention is intended to further improve the accuracy in stabilizing the guide of the flexible optical disk. Since it can be applied to the guide shape and its recording / reproducing system, it can be applied to reproducing optical disks that use embossed pits or other optical disks that record and reproduce light by condensing light, such as magneto-optical recording disks. You can expect a great effect.

As the first stabilizing guide member or the second stabilizing guide member, various shapes and structures can be adopted. For example, those shown in FIGS. 14 to 19 can be exemplified. it can. The stabilizing guide members 40 and 41 shown in FIGS. 14A and 14B have the configuration described in FIG. 7, and have the convex first guide surfaces 40a and 41.
14a, the second guide surfaces 40b and 41b having a concave shape, and the flat surfaces 40c and 41c are formed.
The stabilizing guide member 40 of (a) is arranged in the radial direction of the optical disc along the movement line of the optical pickup, and the stabilizing guide member 41 of FIG. 14 (b) is the movement line of the optical pickup. The optical disk is installed so as to be movable in the radial direction of the optical disk.

In the stabilizing guide members 40 and 41 shown in FIGS. 14A and 14B, the flat surfaces 40c and 41c are formed.
It is also possible to eliminate the above and form only the first guide surfaces 40a and 41a and the second guide surfaces 40b and 41b.

The stabilizing guide member 4 shown in FIGS. 15 and 16.
2 and 43 are convex first guide surfaces 42a and 43a and flat surfaces 42c and 4 in order from the upstream side in the disc rotation direction.
3c and the second guide surfaces 42b and 43b having a convex shape, the stabilizing guide member 4 shown in FIG.
Reference numeral 2 is arranged in the radial direction of the optical disc along the movement line of the optical pickup, and the stabilizing guide member 43 of FIG. 16B is arranged in the radial direction of the optical disc along the movement line of the optical pickup. It is movably installed.

In the stabilizing guide members 42 and 43 shown in FIGS. 16A and 16B, the flat surfaces 42c and 43c are formed.
May be eliminated and only the first guide surfaces 42a, 43a and the second guide surfaces 42b, 43b may be formed,
Alternatively, the second guide surfaces 42b and 43b may be eliminated and only the first guide surfaces 42a and 43a and the flat surfaces 42c and 43c may be formed.

Stabilizing guide member 4 shown in FIGS. 17 and 18.
4 is a convex shape in order from the upstream side in the disc rotation direction,
A first guide surface 44a having a curved surface in a direction orthogonal to the disc rotation direction, a flat surface 44c having a curved side surface in a direction orthogonal to the disc rotation direction, and a convex shape and orthogonal to the disc rotation direction. The second side of the curved surface is curved
The guide surface 44b is formed on the surface. The stabilizing guide member 44 is installed so as to be movable in the radial direction of the optical disc along the movement line of the optical pickup.

In the stabilizing guide member 44 shown in FIGS. 17 and 18, the flat surface 44c may be eliminated and only the first guide surface 44a and the second guide surface 44b may be formed. Without the second guide surface 44b,
It is also possible to form only the first guide surface 44a and the flat surface 44c.

The stabilizing guide member 45 shown in FIG. 19 is basically of a columnar shape and, like the stabilizing guide member 8 shown in FIG. 4, has a curved surface 4 on the end face facing the optical disc 1.
5a is formed on the surface.

FIG. 20 is an explanatory view of a modified example of the relationship between the optical disc and the guide stabilizing member according to the present embodiment. In this example, the center line of the first stabilizing guide member 7 (the air pressure at which it is most protruded The changing portion) is installed on the upstream side of the air flow with respect to the center line (the most protruding portion where the air pressure changes) L _{9 of} the second stabilizing guide member 9.
Therefore, even if both the stabilizing guide members 7 and 9 have the same hemispherical shape, suction is performed from the first stabilizing guide member 7 at the converging point of the objective lens 5 on the optical disc 1 that must be stabilized. The second stabilizing guide member 9 receives a repulsive force, and the optical disc 1 is pushed by the double force with respect to the first stabilizing guide member 7, resulting in a surface wobbling. Can be better suppressed. If the stabilizing guide member is hemispherical, primarily because the repulsive force is at the upstream side of the air flow, also acting suction force, respectively dominant in the downstream side, the center line L ₇ as shown in FIG. 20, By shifting the positional relationship of L ₉ in the direction of the air flow, the force balance can be easily adjusted.

FIG. 21 is an explanatory view of another modification of the relationship between the optical disc and the guide stabilizing member in the present embodiment. The difference between this example and the example shown in FIG. 20 is the second stabilizing guide member. Members having the shape of 9 and corresponding to the members described in FIG. 20 are denoted by the same reference numerals and detailed description thereof will be omitted, but also in this example, the first stabilizing guide member 7 and the second stabilizing guide member 7 are provided. Each center line L in the stabilizing guide member 9
By shifting the positional relationship between ₇ and L ₉ in the direction of air flow,
The balance of forces can be adjusted easily.

The effects of the present embodiment will be specifically verified below with reference to FIGS. 22 to 24.

Members corresponding to those already described in FIG. 22 are designated by the same reference numerals, and detailed description thereof will be omitted.
The first stabilizing guide member 7 has a cylindrical shape with a radius of 50 mm and a diameter of 20 mm, and the second stabilizing guide member 9 has a wedge shape and a prismatic shape with a 20 mm square cross section. The dimensional relationship of each member is as shown in the drawing, and the center line L ₇ , L ₉ of each of the first stabilizing guide member 7 and the second stabilizing guide member ₉ is 3 mm.
is seperated.

FIGS. 23 (a) and 23 (b) are explanatory views of the results of measuring the generation of air pressure in the first stabilizing guide member and the second stabilizing guide member in the configuration example shown in FIG. 22, The vertical axis represents generated air pressure, the origin is atmospheric pressure, and the horizontal axis represents the position from the left end of the first stabilizing guide member.

As shown in FIG. 23 (a), in the first stabilizing guide member 7, on the left side of the first stabilizing guide member 7, the positive pressure is once higher than the atmospheric pressure, and then the first stabilizing guide member 7 is pressed. At the substantially central portion of the stabilizing guide member 7, the negative pressure is suddenly changed. On the other hand, as shown in FIG. 23B, the second stabilizing guide member 9 generates a positive pressure as a whole and acts so as to push the optical disc 1 to the first stabilizing guide member 7. .

Further, the first stabilizing guide member 7 is separated from the second stabilizing guide member 9 by a distance of several tens of μm from the optical disc 1, so that the generated force is small. This force may be large, but since the pressure is determined by the distance between the optical disc 1 and each stabilizing guide member 7, 9,
In this embodiment, the pressure is the first stabilization guide member 7
Is set to be larger.

When the optical disk 1 is pulled upward by the negative pressure of the first stabilizing guide member 7, the optical disk 1 is pushed upward by the positive pressure of the second stabilizing guide member 9, and as a result, 1 is strongly pressed to the first stabilizing guide member 7 side. When the space between the first stabilizing guide member 7 and the optical disc 1 is narrowed by being pressed in this way, the force as an air bearing between the first stabilizing guide member 7 and the optical disc 1 increases, and the first stabilizing guide member 7 and the optical disc 1 increase. The positive pressure on the left side of the stabilizing guide member 7 also increases. Therefore, the sliding contact between the first stabilizing guide member 7 and the optical disk 1 does not occur.

From these facts, the recording / reproducing point is located at the position where the working pressure of the second stabilizing guide member 9 is maximum when the working pressure of the first stabilizing guide member 7 becomes negative. Is ideal (recording / reproducing point = minimum surface deviation point).

Since the second stabilizing guide member 9 is provided in the optical pickup 4 as in the present embodiment, there is a restriction on the shape of the second stabilizing guide member 9 as a protective cover of the objective lens 5. That is, since the second stabilizing guide member 9 has to extend outside the size of the objective lens 5, the first stabilizing guide member 7
And the distance between the center lines L ₇ and L _{9 of} the second stabilizing guide member 9 is determined. The minimum point of the surface deviation in the present embodiment is the center line L of the first stabilizing guide member 7.
_{7 is} on the right side in the drawing, the center line L ₇ of the first stabilizing guide member ₇ is on the right side (3 mm in this embodiment) of the center line L ₉ of the second stabilizing guide member 9. Is desirable.

Table 1 is a table summarizing the results of measurement of the surface wobbling state in the configuration shown in FIG. 22 in the same manner as in the measurement method described in FIG. 5, and on both sides of the optical disk as in this embodiment. With a configuration with a stabilizing guide member installed,
The structure in which the stabilizing guide member was installed on one side of the optical disk was compared with the structure in which the guide member was installed on the entire surface of the optical disk.

[0104]

[Table 1]

As can be seen from Table 1, in the structure of this embodiment, the surface deviation was about 2 μm, and the surface deviation amount was 0.5 μm or less for 90% or more of the time.

Further, in the case where the guide member is extended over the entire surface of the disk as in the conventional example, the scratches caused by the guide member are generated by the rotation for several minutes, but the stabilization is achieved as in the configuration of this embodiment. When the guide member was installed, it was hardly observed visually.

In the optical pickup 4 employing the configuration example of FIG. 22, the tracking error signal observed when the focus servo was turned on was measured. The result is shown in Figure 2.
4 (a) and 4 (b). The wavelength of the light beam emitted from the light source is 405 nm, and the NA of the objective lens 5 is 0.85. The optical disk 1 has a radius of 45 mm and a drive rotation speed of 2000 rpm as described above.

FIG. 24A shows the focus servo off,
FIG. 24B shows the focus servo on. In the optical disc, the tracking error signal is not generated unless the focus servo is turned on and the light condensing point causes an error of about 1 μm or less on the disc recording surface. Figure 24
From (a) and (b), it is proved that the tracking error signal is satisfactorily and uniformly obtained even when the focus servo is off, and that the focus error is extremely small in the present embodiment. The fact that the error is small without focus servo in this way corresponds to the fact that the surface deviation of the optical disc is extremely small, and can be said to be proof data of the effectiveness in the present embodiment.

As described above, according to each of the above-described embodiments, the flexible optical disk 1 is made to face both stabilizing guide members (for example, the first stabilizing guide member 7 and the second stabilizing guide member 9). When rotated in the position, the first stabilizing guide member 7 on the substrate side of the optical disc 1 is moved to the optical disc 1
By generating a positive pressure on the upstream side with respect to the rotational direction, a repulsive force acts on the optical disc 1 and the first stabilizing guide member 7 at that portion, and the optical disc 1 is stabilized at a certain distance for the first stabilization. It floats up with respect to the guide member 7. Further, by changing the shape of the first stabilizing guide member 7 on the downstream side in the rotation direction to generate a negative pressure, the optical disc 1 receives the suction force to the side of the first stabilizing guide member 7 at that portion. However, since the optical disc 1 has a certain degree of rigidity, it does not immediately come into contact with the first stabilizing guide member 7 to cause rubbing.

Further, the optical pickup 4 side (recording film side of the optical disc 1) is also provided with the second stabilizing guide member 9 which mainly generates an acting force from the pickup 4 side to the optical disc 1 side, so that the optical pickup Since the repulsive force from the 4 side to the optical disc 1 and the double force in the same direction as the attraction force to the first stabilizing guide member 7 on the substrate side of the optical disc 1 act, the surface blur stabilization is better performed. .

As described above, the optical disk 1 receives a repulsive aerodynamic force from the one first stabilizing guide member 7 arranged on the substrate side, and thereafter, is attracted in a direction opposite to the aerodynamic force. By receiving the repulsive force from the second stabilizing guide member 9 disposed on the optical pickup side at the same time, the optical disc 1 and the second stabilizing guide member 9 maintain a certain fixed distance, Moreover, the optical disk rotates while this distance is stable. Therefore, by condensing the recording / reproducing light on this stable region, it becomes possible to perform the recording / reproducing on the region of the optical disc 1 where the surface deviation and tilt are small.

Since the first stabilizing guide member 7 also generates a suction force, the second stabilizing guide member 9 mainly generates a repulsive force, so that the optical disc 1 is first stabilized on the substrate side. It will rotate at a position close to the guide member 7.
Therefore, the optical disc 1 does not rotate near the side of the optical pickup 4 where the recording film is present, so that no sliding scratches occur on the recording film.

Since the aerodynamic force is used for the above-mentioned stabilization and the substrate forming the optical disc has a low rigidity, it is not necessary to produce the optical disc itself with high precision, and a large surface wobbling is eliminated. Therefore, the structure of the optical pickup for recording / reproducing does not have to follow a large surface deviation, so that defocus is reduced and high-density recording / reproducing can be stably performed. .

Further, from this, as the actuator of the objective lens constituting the optical pickup, a high rigidity actuator is used as the elastic member (spring) for supporting the actuator, instead of not responding to the large amplitude in the low frequency band. As a result, it is possible to configure an optical pickup having a characteristic that high-frequency resonance exists on the high frequency side. Therefore, the operation of the servo system can be speeded up, and the defocus amount can be suppressed even at a higher linear velocity.

Further, by providing a region in which the aerodynamic force is not applied according to Bernoulli's theorem at an arbitrary position on the upstream side and the downstream side of the disc rotation direction in the disc rotation direction than the portion where the face deflection is stabilized in the optical disc, the surface deflection is more improved. It will be effectively suppressed. The reason for this is that the flexible optical disk is deformed by the stabilization guide member and the stabilization area of the optical disk is forcibly generated at the light converging point. This is because if the optical disc is provided with a "relief" portion, the repulsive force of the optical disc in the stabilization area can be reduced, and the effect of the aerodynamic stabilizing force is increased.

In the conventional structure in which the flat plate guide member is installed opposite to the entire surface of the flexible disk, a stabilizing surface is provided corresponding to the entire surface of the disk, and a flat plate larger than the disk is installed. Met. Therefore, when this configuration is applied to a recording / reproducing apparatus using an optical disc, the surface blur of the optical disc is stabilized even in the periphery other than the condensing point of the optical pickup, which is a portion where the surface blur is desired to be stabilized. Therefore, when the optical disc has undulations, even if it is desired to stabilize the vicinity of the converging point, the bending force from the front and rear (upstream and downstream) positions in the disc rotation direction acts strongly, and the surface wobbling is reduced. The stabilizing effect may be inadequate.

In the case of an optical disc having a structure in which the recording layer is formed on a flexible substrate, the substrate is likely to warp on the side opposite to the film forming surface. Therefore, as in the present embodiment, when the stabilizing guide member is guided by the aerodynamic force on the substrate side of the optical disc, the stabilizing action is achieved by the returning force of the substrate itself and the repulsive force of the stabilizing guide member. Can be satisfactorily performed. From this,
In this embodiment, a stabilizing guide member is arranged on the substrate side of the optical disc, and an optical pickup is arranged on the recording layer side to perform recording / reproduction. With such a structure, even if the optical disc and the optical pickup are in a sliding state and the optical disc is scratched, the scratch does not occur on the recording layer side, so that a recording / reproducing error occurs. Does not cause. Further, because of such a configuration, the recording / reproducing light does not pass through the substrate of the optical disc,
The recording / reproducing characteristics are not affected by scratches and the optical characteristics of the substrate.

Although the optical recording / reproducing apparatus has been described as an example in the above embodiment, a flexible information recording / reproducing apparatus such as an information recording / single function apparatus or an information / reproduction single function apparatus is used. The same effect can be obtained by applying it to a device using the optical disc.

[0119]

As described above, according to the present invention,
The stabilizing means for stabilizing the surface wobbling in the direction of the rotation axis in the region where writing and / or reading is performed on the flexible sheet-shaped optical disc by the pressure difference of the airflow based on Bernoulli's law is provided on both sides of the disc. And the areas where the surface wobbling is stabilized by both stabilizing means are provided in a well-balanced region in which the pressure difference of the air flow does not occur between the upstream side and the downstream side in the disk rotation direction of the part of the optical disk. Since the stabilizing effect is increased, high-density writing can be performed in the stabilized portion.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of an optical information recording / reproducing apparatus for explaining a first embodiment of the present invention.

FIG. 2 is an explanatory diagram of a recording unit and a reproducing unit that constitute the optical pickup according to the embodiment of the present invention.

FIG. 3 is a sectional view showing an example of an optical disc according to an embodiment of the present invention.

FIG. 4 is an explanatory diagram for explaining stabilization of surface deviation of the optical disc according to the embodiment of the present invention.

5 is a diagram showing a measurement result of surface deviation of an optical disc measured for the configuration example shown in FIG.

FIG. 6 is a flowchart relating to an operation at the time of recording / reproducing in the embodiment of the present invention.

FIG. 7 is an explanatory diagram showing a modified example of the stabilizing guide member according to the first embodiment.

FIG. 8 is an explanatory diagram of an arrangement example of a stabilizing guide member according to the first embodiment.

FIG. 9 is a schematic configuration diagram of an optical information recording / reproducing apparatus for explaining a second embodiment of the present invention.

FIG. 10 is a schematic configuration diagram of an optical information recording / reproducing apparatus for explaining a third embodiment of the present invention.

FIG. 11 is an explanatory view of an arrangement example of a stabilizing guide member in the third embodiment.

FIG. 12 is a plan view for explaining an embodiment of a disc cartridge of the present invention.

13 is a partial cross-sectional view taken along the line AA in FIG.

FIG. 14 is an explanatory diagram showing a configuration example of a stabilizing guide member in the embodiment of the present invention.

FIG. 15 is an explanatory view showing a configuration example of a stabilizing guide member in the embodiment of the present invention.

FIG. 16 is an explanatory diagram showing a configuration example of a stabilizing guide member in the embodiment of the present invention.

FIG. 17 is an explanatory view showing a configuration example of a stabilizing guide member in the embodiment of the present invention.

FIG. 18 is an explanatory diagram showing a configuration example of a stabilizing guide member in the embodiment of the present invention.

FIG. 19 is an explanatory view showing a configuration example of a stabilizing guide member in the embodiment of the present invention.

FIG. 20 is an explanatory diagram of a modified example of the relationship between the optical disc and the guide stabilizing member according to the present embodiment.

FIG. 21 is an explanatory diagram of another modification of the relationship between the optical disc and the guide stabilizing member according to the present embodiment.

FIG. 22 is an explanatory diagram of a configuration example for observing the effects of this embodiment.

23 (a) and (b) are explanatory views of the results of measuring the air pressure generation between the first stabilizing guide member and the second stabilizing guide member in the configuration example shown in FIG.

24 (a) and 24 (b) are waveform diagrams of tracking error signals observed during focus servo off and focus servo on in the configuration example shown in FIG.

[Explanation of symbols]

1 optical disc 1a hub 2 spindle shaft 3 spindle motor 4 Optical pickup 5 Objective lens 6 Pickup positioning mechanism 7, 9, 25, 30, 40-45 Stabilizing guide member 8 Stabilization guide positioning mechanism 10 Device body 14 Laser light source 17 Photoelectric conversion element 20 Optical disc recording layer 21 Optical disc substrate 25a Positive pressure generating portion of stabilizing guide member 25b Negative pressure generating part of stabilizing guide member 25c Flat part of stabilizing guide member 27,33 disk cartridge 34 Disc tray 35 Disc tray identification section

Continued front page    (72) Inventor Shozo Murata             1-3-3 Nakamagome, Ota-ku, Tokyo Stocks             Company Ricoh

Claims (19)

[Claims] 1. A rotation driving means for rotating a flexible sheet-shaped optical disc and a shake in the direction of the rotation axis at a portion of the optical disc where writing or reading is performed are stabilized by a pressure difference of an air flow based on Bernoulli's law. An optical disk drive device comprising a stabilizing means for stabilizing the optical disc, wherein the stabilizing means is installed on both sides of the optical disc, and the disc rotation direction of the portion of the optical disc in which the surface deviation is stabilized by both stabilizing means. An optical disk drive device, characterized in that a region that does not cause a pressure difference of the air flow is provided on the upstream side and the downstream side. 2. The optical disk drive device according to claim 1, wherein the stabilizing means is provided on a recording surface side of the optical disk and on a surface opposite to the recording surface side. 3. The optical disk drive device according to claim 1, wherein the stabilizing means installed on the recording surface side generates a repulsive force to the optical disk. 4. The distance between the optical disk and the stabilizing means installed on the recording surface side is set longer than the distance between the optical disk and the stabilizing means installed on the opposite surface side to the recording surface. 4. The optical disk drive device according to claim 1, 2, or 3. 5. The most prominent part of the stabilizing means installed on the recording surface side and the stabilizing part installed on the side opposite to the recording surface with respect to the part of the optical disk where writing or reading is performed. 5. The optical disk drive device according to claim 1, wherein the most projecting part of the means is arranged so as to be displaced in the circumferential direction of the optical disk. 6. A rotation driving means for rotating a flexible sheet-shaped optical disk, an optical writing means for writing information by converging on a recording surface of the optical disk, and the optical writing means. An optical information recording apparatus comprising: a stabilizing unit that stabilizes a shake in a rotation axis direction at a portion where writing is performed on an optical disc by a pressure difference of an air flow based on Bernoulli's law, the stabilizing unit Are provided on both sides of the optical disk, and areas where the surface deviation is stabilized by both stabilizing means are provided on the upstream side and the downstream side in the disk rotation direction of the portion of the optical disk where the pressure difference of the air flow is not generated. An optical information recording device characterized by the above. 7. The optical information recording apparatus according to claim 6, wherein the stabilizing means is provided on the recording surface side of the optical disc and on the surface opposite to the recording surface side. 8. The optical information recording apparatus according to claim 6, wherein the stabilizing means installed on the recording surface side generates a repulsive force to the optical disk. 9. The optical information recording apparatus according to claim 6, wherein the stabilizing means installed on the recording surface side is fixed to the optical disk side of the optical writing means. . 10. An optical disk is controlled by an objective lens for condensing provided in the optical writing means to control an installation distance of the stabilizing means fixed to the upper part of the optical writing means with respect to the optical disk. 10. The optical information recording device according to claim 9, wherein the distance is set shorter than the closest distance. 11. The distance between the stabilizing means installed on the recording surface side and the optical disk is set longer than the distance between the stabilizing means installed on the side opposite to the recording surface and the optical disk. The optical information recording device according to any one of claims 6 to 10, which is characterized in that. 12. The most projecting portion of the stabilizing means installed on the recording surface side is opposite to the recording surface with respect to the portion where the optical writing means condenses the optical disk. 12. The optical information recording according to any one of claims 6 to 11, characterized in that the most projecting portion of the stabilizing means installed on the surface side is arranged so as to be offset with respect to the circumferential direction of the optical disc. apparatus. 13. A rotation driving means for rotating a flexible sheet-shaped optical disc, an optical reading means for converging on a recording surface of the optical disc and reading information by reflected light, and this optical reading means. An optical information reproducing apparatus comprising: a stabilizing unit that stabilizes the shake in the direction of the rotation axis at the portion where the optical disc is read by the optical disc according to Bernoulli's law. Means are respectively installed on both sides of the optical disk, and areas for preventing the pressure difference of the airflow are provided on the upstream side and the downstream side in the disk rotation direction of the part of the optical disk where the surface deviation is stabilized by both stabilizing means. An optical information reproducing device characterized by the above. 14. The optical information reproducing apparatus according to claim 13, wherein the stabilizing means is provided on a recording surface side of the optical disc and on a surface opposite to the recording surface side. 15. The optical information reproducing apparatus according to claim 13, wherein the stabilizing means installed on the recording surface side generates a repulsive force to the optical disk. 16. The optical information reproducing apparatus according to claim 13, wherein the stabilizing means installed on the recording surface side is fixed to the optical disk side of the optical reading means. 17. The converging objective lens provided in the optical reading means is closest to the optical disk by a control operation with respect to the facing installation distance to the optical disk in the stabilizing means fixed to the upper part of the optical reading means. 17. The optical information reproducing device according to claim 16, wherein the optical information reproducing device is set shorter than the distance. 18. The distance between the stabilizing means installed on the recording surface side and the optical disk is set longer than the distance between the stabilizing means installed on the side opposite to the recording surface and the optical disk. The optical information reproducing device according to any one of claims 13 to 17, which is characterized in that. 19. A surface opposite to the recording surface and the most projecting portion of the stabilizing means installed on the recording surface side with respect to the portion where the optical reading means condenses the optical disk. The optical information reproducing apparatus according to any one of claims 13 to 18, wherein the most protruding portion of the stabilizing means installed on the side is arranged so as to be offset from the circumferential direction of the optical disc. .