JP2005050404A - Recording and reproducing device and its control adjusting method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To surely suppress a face wobbling of a disk even when an optical pickup having a small work distance is used as a recording/reproducing means. <P>SOLUTION: An objective lens 7 is embedded in a casing 4a of the optical pickup 4, and the gap quantity at the closest position of a surface opposed to an optical disk 1 in the objective lens 7 is fixed without changing, then a focus servo operation system 9 consisting of a focus servo mechanism is installed at the separate position of an optical pickup system. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a recording / reproducing apparatus that performs recording and / or reproducing processing on a flexible recording disk, and a control adjustment method applied to the recording / reproducing apparatus.
[0002]
[Prior art]
In recent years, there has been a demand for information recording media to record large volumes of digital data, such as the start of digitization of television broadcasting. In the field of optical discs, reducing the diameter of the light spot focused on the optical disc for recording / reproduction is one of the basic methods for increasing the density.
[0003]
For this reason, in increasing the density of the optical disk, it is effective to shorten the wavelength of light used for recording / reproduction and increase the numerical aperture NA of the objective lens. As for the wavelength of light, a wavelength of near infrared light of 780 nm is used for CD (compact disk), and a wavelength of about 650 nm of red light is used for DVD (digital versatile disk). Recently, a blue-violet semiconductor laser has been developed, and it is expected that a laser beam of around 400 nm will be used in the future.
[0004]
As for the objective lens, it was less than NA0.5 for CD, but it is about NA0.6 for DVD. In the future, it is required to further increase the numerical aperture (NA) to NA or more 0.7. However, increasing the NA of the objective lens and shortening the wavelength of light also increase the influence of aberrations when focusing light. Therefore, the margin for the tilt of the optical disk is reduced. Further, since the depth of focus is reduced by increasing the NA, the focus servo accuracy must be increased.
[0005]
In addition, since the distance between the objective lens and the recording surface of the optical disk is reduced by using a high NA objective lens, the optical disc surface blur must be kept small before the focus servo at the start is pulled. The objective lens and the optical disk may collide, causing a pickup failure.
[0006]
As a short-wavelength, high-NA high-capacity optical disk, for example, as described in Non-Patent Document 1, a recording film is formed on a substrate that is as thick as a CD and has high rigidity, and is used for recording / reproducing light. Has been proposed which records / reproduces data on / from a recording film through a thin cover layer without passing through the substrate.
[0007]
Further, for example, as described in Patent Documents 1 to 3, in order to stabilize the surface blur in the optical disk by utilizing the aerodynamic action force according to Bernoulli's law, flexibility is provided by facing the stabilizing member. There is a recording / reproducing apparatus configured to rotate an optical disk.
[0008]
[Patent Document 1]
Japanese Patent Laid-Open No. 10-308059
[Patent Document 2]
US Patent Application Publication No. 2002/0186636
[Patent Document 3]
JP 2003-115108 A
[Non-Patent Document 1]
O PLUS E Vol. 20, No. 2, P.E. 183
[Non-Patent Document 2]
“Optical Lead-Out of Video Disc”, “EITA TRANSPORTATION ON CONSUMER ELECTRONICS”, November 1976, P.I. 304-308
[0009]
[Problems to be solved by the invention]
However, in the prior art, when the substrate of the optical disk is formed of a rigid body, in order to reduce surface deflection and tilt in the rotating optical disk, extremely accurate molding is performed and recording is performed at a low temperature so that thermal deformation does not occur. A film must be deposited. This prolongs the tact time associated with optical disc manufacture and increases costs.
[0010]
Further, as described in Patent Document 1, in the configuration in which a flexible optical disk is rotated on a stabilizing plate formed of a mere flat plate, the disk surface shake cannot be sufficiently reduced. There is a high risk that the optical disc and the stabilization plate will slide in contact with each other due to large disc surface fluctuation, and the disc surface or the stabilization plate surface may be damaged. For the same reason, the risk of collision between the objective lens and the optical disc still remains a problem when using a high NA objective lens.
[0011]
As one of the methods using the stabilization plate, there is a method as described in Non-Patent Document 2, but it is the same as the above technique in terms of the configuration of using a planar stabilization plate, and the same problem Is expected to occur.
[0012]
As one means for solving these problems, the present inventor disclosed in Patent Documents 2 and 3 using a cylindrical stabilization guide member whose surface facing the optical disk forms an arc shape, and a stabilization guide for the optical disk. Areas where no air pressure action is generated (a space part without a stabilizing guide member) are provided on the upstream side and the downstream side in the disk rotation direction at the part where the surface shake due to the air pressure action by the member is stabilized, thereby stabilizing the face shake. Invention that increases the effect of stabilizing force by aerodynamic force by reducing the repulsive force in the optical disk at the part where the surface blurring is stabilized by making the optical disk have a portion that becomes “escape” at the front and rear positions of the part Proposed.
[0013]
According to the inventions of Patent Documents 2 and 3, it is possible to reliably suppress surface deflection of the flexible optical disk, enable high-density recording, and prevent occurrence of problems such as sliding contact with the objective lens. Become. However, even in the present invention, depending on the proximity distance between the objective lens of the optical pickup and the recording surface of the optical disc, there is a problem that unauthorized vibration is superimposed on the disc surface blur.
[0014]
Moreover, in general focus servo operation of an optical disk, the fluctuation of the objective lens surface in the direction of the disk rotation axis is accompanied. However, the vibration phenomenon is also superimposed, and the vibration phenomenon is complicated. . This phenomenon is particularly problematic when a high NA lens with a small lens diameter is used, that is, when an optical pickup with a small work distance (actual movement distance) is used.
[0015]
An object of the present invention is to solve the above-mentioned problems, and even when an optical pickup with a small work distance is used as a recording / reproducing means, the disc surface fluctuation is reliably suppressed, and a stable recording / reproducing operation at a recording / reproducing position is achieved. An object of the present invention is to provide a recording / reproducing apparatus that can be used and a control adjustment method applied to the recording / reproducing apparatus.
[0016]
[Means for Solving the Problems]
In order to achieve the above-mentioned object, the invention according to claim 1 is a stable recording apparatus that rotates a flexible recording disk and uses the Bernoulli effect to suppress at least the recording / reproducing position near the recording / reproducing position. A recording member provided with an objective lens for condensing a light beam on the optical information recording medium in order to perform recording and / or reproduction on a surface opposite to the main Bernoulli effect operating surface of the recording disk In the recording / reproducing apparatus including the reproducing unit, the gap amount at the closest position of the surface facing the recording disk of the objective lens and the closest position of the surface facing the recording disk of the stabilizing member The gap amount in the recording medium is fixed at least during recording / reproduction. / Aerodynamic forces acting by reproducing means and the stabilizing member will be able to be kept constant, it is possible to reduce the disk surface vibration effectively.
[0017]
According to a second aspect of the present invention, in the recording / reproducing apparatus according to the first aspect, the objective lens is fixed to the casing of the recording / reproducing means, and the recording / reproducing means at a part different from the installation position of the objective lens Since the focus servo mechanism is provided in the optical system that constitutes the lens, and this configuration makes it possible to perform the focus servo operation with the objective lens fixed, a general recording / reproducing means ( It is possible to prevent the abnormal vibration from being superimposed on the disc surface shake due to the focus servo operation, which is a problem in the optical pickup).
[0018]
According to a third aspect of the present invention, in the recording / reproducing apparatus according to the first or second aspect, the main shape in the disk circumferential direction on the surface including the objective lens facing the recording disk of the recording / reproducing means is a convex curved surface. This configuration makes it possible to cause aerodynamic force to act properly on the recording disk surface, so even when the objective lens of the optical pickup and the recording surface of the recording disk are brought close to each other. In addition, the disc surface shake can be stabilized without superimposing improper vibration on the disc surface shake.
[0019]
According to a fourth aspect of the present invention, in the recording / reproducing apparatus according to the first or second aspect, the main shape in the disk circumferential direction on the surface of the stabilizing member facing the recording disk is a convex curved surface. With this configuration, an aerodynamic force can be appropriately applied to the recording disk surface.
[0020]
According to a fifth aspect of the present invention, in the recording / reproducing apparatus according to any one of the first to fourth aspects, the disk circumferential direction shape on the surface including the objective lens facing the recording disk of the recording / reproducing means is a circular approximation. The curvature radius of the curved line is larger than the curvature radius of the curved line obtained by circularly approximating the circumferential shape of the disk on the surface of the stabilizing member facing the recording disk. Since the gap between the reproducing means and the recording disk can be increased and the gap between the stabilizing member and the recording disk can be reduced, for example, the gap between the recording / reproducing means and the recording disk can be recorded / reproduced. Set to a desired work distance (for example, 50 to 500 μm for an optical pickup with NA of 0.85), and between the stabilizing member and the recording disk. The gap, it is possible, as set in the desired value (0.1 number Myuemu～20myuemu) in air stabilizer.
[0021]
According to a sixth aspect of the present invention, in the recording / reproducing apparatus according to any one of the first to fourth aspects, the width of the disk circumferential direction on the surface of the recording / reproducing means facing the recording disk is set to It is characterized in that it is larger than the width in the disk circumferential direction on the surface facing the recording disk. With this configuration, the same effect as that of the invention according to claim 5 can be obtained.
[0022]
A seventh aspect of the present invention is the recording / reproducing apparatus according to any one of the first to fourth aspects, wherein the disk circumferential direction shape on the surface including the objective lens facing the recording disk of the recording / reproducing means is a circular approximation. The curvature radius of the curved line is made larger than the curvature radius of the curved line obtained by circularly approximating the circumferential shape of the disk on the surface of the stabilizing member facing the recording disk, and the disk on the surface facing the recording disk of the recording / reproducing means The width in the circumferential direction is made larger than the width in the disk circumferential direction on the surface of the stabilizing member facing the recording disk, and this configuration also has the same effect as that of the invention according to claim 5. can get.
[0023]
The invention according to claim 8 is a control adjustment method used in the recording / reproducing apparatus according to any one of claims 1 to 7, wherein the gap between the recording / reproducing means and the stabilizing member is provided. By adjusting the amount, the gap amount between the recording / reproducing means and the recording disk is adjusted so as to be substantially equal to the actual moving distance of the recording / reproducing means. An appropriate focus servo operation can be performed.
[0024]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0025]
FIG. 1 is a schematic diagram of a front configuration for explaining Embodiment 1 of the recording / reproducing apparatus of the present invention, FIG. 2 is an explanatory view showing an enlarged main part in Embodiment 1, and 1 has flexibility. An optical disk that is a recording disk, 2 is a hub that is one holding member for rotating the optical disk 1 that is mounted on the rotation center (center) portion of the optical disk 1, and 3 is a chucking portion that is the other holding member. A spindle motor that fits into the hub 2 and rotationally drives the optical disk 1, 4 is an optical pickup as recording / reproducing means, and 5 moves in the radial direction of the optical disk 1 together with the optical pickup 4, and is aerodynamic according to Bernoulli's law. A main stabilizing member 7 that suppresses surface blurring of the optical disc at least in the vicinity of the recording / reproducing position by the optical pickup 4 in the optical disc 1 by using the acting force. Is fixed to the housing 4a of up 4, a laser beam emitted from the laser light source provided in the optical pickup 4 condensed to a beam spot on the optical disk 1, also is an objective lens for receiving the reflected beam from the optical disk 1.
[0026]
Note that the present embodiment and examples include a description of a system in which an auxiliary stabilizing member 6 to be described later is provided, so that the stabilizing member 5 provided corresponding to the recording / reproducing position in the optical pickup 4 is provided. Called the main stabilizing member.
[0027]
In FIG. 2, reference numeral 9 denotes a focus servo operation system (described in detail later) disposed in a different part of the optical system of the optical pickup 4 from the objective lens 7, and 10 denotes a disk circle on the surface of the housing 4 a of the optical pickup 4. An approximate circle in the circumferential direction is shown.
[0028]
It should be noted that the position of the focus servo operation system 9 indicates that it is on the laser optical axis, and is not limited to this position. Needless to say, the optical pickup 4 includes other components (not shown) such as a laser light source and a tracking servo drive system as is well known. As for the tracking servo drive system, for example, a configuration in which the tracking servo drive system is also used as the illustrated focus servo operation system 9 can be considered.
[0029]
In the first embodiment, the main stabilizing member 5 has a shape in which at least the effective area width in the disk circumferential direction is Wg and the disk circumferential direction of the surface facing the optical disk 1 is an arbitrary curvature radius Rg. For the disk radial direction, for example, various patterns such as a shape extending in the disk radial direction, a shape having a specific radius of curvature, or an aspherical shape in which the curvature changes depending on the part are considered. However, the present embodiment is not particularly limited.
[0030]
Further, in the present embodiment, for simplicity of explanation, the surface shape in the disc circumferential direction of the main stabilizing member 5 is fixed to an arbitrary curvature radius. However, for example, the radius of curvature in the disc circumferential direction is used. Including an aspherical shape in which is continuously changed, or a shape in which only an arbitrary length region in the disk radial direction is linear. At this time, the radius of curvature in the case of circular approximation of the shape in the circumferential direction of the disk is equivalent to the above-described form by setting it to Rg.
[0031]
As shown in FIG. 2, the optical pickup 4 has a disc circumferential shape that passes through the center of the objective lens 7 and has a radius of curvature Rp1 at the upstream portion of the disc rotation, RL at the objective lens surface, and at the downstream portion of the disc rotation. The effective area width in the disk circumferential direction is Wp. Further, the radius of curvature of the approximate circle 10 when the surface shape 11 whose radius of curvature changes such as Rp1, RL, Rp2 is approximated by a circle is Rp. The relationship between the approximate circle 10 having the radius of curvature Rp approximated by this circle and the surface shape 11 of the optical pickup is, for example, as shown in an enlarged explanatory diagram shown in FIG.
[0032]
The objective lens 7 is fixed by being embedded in the housing 4a of the optical pickup 4, and the final surface of the optical pickup 4 including the objective lens 7 has a convex curved surface determined by the shape parameters as described above.
[0033]
As shown in FIG. 2, in the first embodiment, the relationship between the parameters related to the shape of the recording disk facing surface of the main stabilizing member 5 and the optical pickup 4 is set to be Wg = Wp, Rg <Rp.
[0034]
In the first embodiment, by adjusting the gap amount between the main stabilizing member 5 and the optical pickup 4, the gap amount between the optical pickup 4 and the optical disc 1 becomes substantially equal to the actual moving distance (work distance) of the optical pickup 4. Adjust as follows.
[0035]
FIG. 4 is a cross-sectional view of an essential part for explaining Embodiment 2 of the recording / reproducing apparatus of the present invention. In the following description, members corresponding to those described in FIGS. 1 to 3 are denoted by the same reference numerals, and detailed description thereof is omitted.
[0036]
The difference between the second embodiment and the first embodiment is that the relationship between the main stabilizing member 5 and the optical pickup 4 on the optical disk facing surface shape is such that Wg <Wp, Rg = Rp.
[0037]
FIG. 5 is a cross-sectional view of a main part for explaining the third embodiment of the recording / reproducing apparatus of the present invention. The third embodiment is different from the first embodiment in that the main stabilizing member 5 and the optical pickup 4 are This is because the relationship of parameters relating to the shape of the optical disc facing surface is such that Wg <Wp, Rg <Rp.
[0038]
The operation of each embodiment will be described.
[0039]
In each of the above embodiments, basically, an aerodynamic force according to Bernoulli's law is generated between the main stabilizing member and the flexible optical disc to suppress disc surface blurring. As a result of various experiments, a considerable amount of aerodynamic force is applied to the optical disc even by the optical pickup located on the opposite side across the main stabilizing member and the disc. It became clear that adjustment was necessary. Further, in this adjustment, the main stabilizing member and the shape of the optical pickup in the disk circumferential direction were found to be important factors.
[0040]
The aerodynamic optical disk stabilization phenomenon related to the shape and the adjustment method will be described below.
[0041]
As shown in FIG. 6, when a member (stabilizing member) 15 having an arbitrary radius of curvature in the disc circumferential direction is arranged so as to sandwich the optical disc 1, and the gap amount between both members 15 is D12, The optical disc 1 is deviated by an arbitrary amplitude in accordance with the aerodynamic force applied from both members 15 around the arbitrary position between both members 15. At this time, in order to effectively reduce the disk surface shake, it is necessary to appropriately adjust the action of the aerodynamic force. In this adjustment, it is effective to reduce the proximity distance between at least one of the members 15 and the optical disk 1 to increase the aerodynamic vibration damping effect. This adjustment can be realized by adjusting the shape of both members 15 in the disk radial direction.
[0042]
In the configuration shown in FIG. 6, the following relationship exists between this shape and the gap amount of each part. That is, if the radius of curvature of both members 15 is R1 = R2, and the effective area width is W1 = W2, the gap amount of each part shown in the figure is D1 = D2.
[0043]
Further, if the radius of curvature of both members 15 is R1 <R2, and the effective area width is W1 = W2, the gap amount of each part shown in the figure is D1 <D2.
[0044]
Further, when the radius of curvature of both members 15 is R1 = R2, and the effective area width is W1 <W2, the gap amount of each part shown in the figure is D1 <D2.
[0045]
Further, if the radius of curvature of both members 15 is R1 <R2, and the effective area width is W1 <W2, the gap amount of each part shown in the figure is D1 << D2.
[0046]
For example, the upper member in FIG. 6 corresponds to the main stabilizing member and the lower member corresponds to the optical pickup. In the first to third embodiments described above, the gap amount with the optical disc 1 on the main stabilizing member 5 side is reduced based on the above relationship. In this way, by effectively reducing the gap amount Dg between the stabilizing member 5 and the optical disc 1 and improving the aerodynamic damping effect, it is possible to obtain an effective effect of reducing disc surface blurring. it can.
[0047]
Further, according to the results of various experimental studies, in order to reduce the disc surface fluctuation to, for example, 10 μm or less by the main stabilizing member 5, the gap amount Dg on the main stabilizing member side in FIGS. The gap amount Dp between the optical pickup 4 side and the optical disc 1 is limited by the work discance of the optical pickup 4 and is preferably in the range of 50 μm to 500 μm. It is in. That is, Dg and Dp inevitably require a magnitude relationship of Dg <Dp. In addition to reducing the Dg for reducing the disk surface shake, the realization of this magnitude relationship is also considered.
[0048]
For example, as another method, it is possible to increase the surface blur reduction effect of the optical disc 1 by bringing the main stabilization member 5 and the optical pickup 4 close to each other. Since the proximity distance is limited and the effect of reducing the surface blur is limited accordingly, it is not practical.
[0049]
In order to achieve the above-described effect, it is desirable that the surfaces of the main stabilizing member 5 and the optical pickup 4 that face the optical disc 1 are convex curved surfaces having at least no protrusions. For example, in the configuration of FIG. 6, when a projecting portion (incorrect shape) that is not a convex curved surface exists on the working surface of the member 15 with respect to the optical disc 1, the aerodynamic disc surface stabilization condition is disturbed, There is a problem that abnormal vibration is superimposed on the disc surface shake.
[0050]
The abnormal vibration changes according to the proximity distance between the member 15 and the optical disc 1, and the influence increases as the distance becomes closer. For example, in a general optical pickup, the irregular shape is formed by the arrangement structure of the objective lens in the housing of the optical pickup, which causes abnormal vibration of the disk surface. In particular, when an optical pickup having a small lens diameter and a high NA is used, the abnormal vibration becomes larger because the optical pickup needs to be close to the disk surface.
[0051]
Therefore, in the first to third embodiments, in order to eliminate the irregular shape, the objective lens 7 is embedded and fixed in the housing 4a of the optical pickup 4, and the schematic outer shape of the final optical pickup 4 including the objective lens 7 is fixed. Is a convex curved surface.
[0052]
Moreover, in the general optical pickup 4, the position of the objective lens 7 is made to follow according to the disc surface fluctuation. That is, since the dynamic control is performed so that the laser beam is focused near the recording layer of the optical disc 1 by performing the focus servo operation, the objective lens 7 vibrates in the disc rotation axis direction near the surface of the optical disc 1. In this state, the vibration causes the abnormal vibration to be superimposed on the disc surface shake.
[0053]
In order to cope with this, in the first to third embodiments, the objective lens 7 is embedded and fixed in the housing 4a of the optical pickup 4, and a focus servo operation system 9 including a focus servo mechanism is installed in another part of the optical pickup system. Thus, the abnormal vibration is prevented.
[0054]
Note that the present embodiment is not limited to the configuration of the recording / reproducing apparatus shown in FIG. 1, but a flexible disk-shaped optical information recording medium is rotated and at least near the recording / reproducing position using the Bernoulli effect. A stabilizing member that suppresses surface wobbling of the optical information recording medium, and an optical pickup that is a recording / reproducing means for performing recording and / or reproduction on a surface opposite to a main working surface of the Bernoulli effect of the optical information recording medium. Any recording / reproducing apparatus can be applied.
[0055]
For example, as in the recording / reproducing apparatus shown in the plan view of FIG. 7 and the front view of FIG. 7 of FIG. 8, auxiliary stabilization is performed at a position ± 90 degrees upstream and downstream of the disk rotation direction with respect to the installation position of the main stabilization member 5. As shown in the plan view of FIG. 9 and the recording / reproducing apparatus shown in the front view of FIG. 9 in FIG. As shown in the plan view of FIG. 11 and the recording / reproducing apparatus shown in the front view of FIG. 11 of FIG. 12, the main stabilizing member 5 of the main stabilizing member 5 is arranged in the two regions. Any of the configurations in which the auxiliary stabilizing member 6 is disposed at a position of ± 90 degrees upstream and downstream in the disk rotation direction with respect to the installation position, and the main stabilizing member 5 is formed in a substantially rectangular shape and extends in the disk radial direction. Or modify these configurations The present embodiment can also be applied to other configurations.
[0056]
11 and 12, the effective area width (W1, W2) in the disk circumferential direction of the main stabilizing member 5 has a shape (W1 <W2) that varies along the disk radial direction. However, in such a case, the surface shape of the optical pickup 4 with respect to the portion W2 may be adjusted as described above with reference to the portion W2 having the largest effective basin width.
[0057]
11 and 12, when the radius of curvature of the main stabilizing member 5 in the disk circumferential direction is changed along the disk radial direction, the region having the largest radius of curvature is used as a reference. As described above, the surface shape of the optical pickup 4 with respect to the portion may be adjusted.
[0058]
Next, a configuration example of an optical pickup applied to the recording / reproducing apparatus according to the present invention will be described more specifically.
[0059]
FIG. 13 is a schematic configuration diagram of the optical pickup of the present embodiment, in which 21 is a hologram unit, 22 is a collimating lens, and 23 is a rising mirror composed of a deflection prism. As shown in FIG. 14, the hologram unit 21 includes a laser light source LD, a hologram element HOE for diffracting the reflected light from the optical disk 1, and a divided light receiving element PD for generating various signals. Is provided.
[0060]
In FIG. 13, the divergent light beam from the hologram unit 21 is collimated by the collimator lens 22, reflected by the rising mirror 23, and condensed on the recording surface of the optical disk 1 by the objective lens 7. The reflected light from the optical disc 1 is incident on the hologram unit 21 again, and various signals are generated by the divided light receiving element PD.
[0061]
The objective lens 7 is fixed to the housing 4 a of the optical pickup 4, and the surface shape on the optical pickup 4 side facing the optical disc 1 is a convex curved surface including the objective lens 7.
[0062]
FIGS. 15A to 15C are side views showing the outer shape of the optical pickup 4, and 24 and 25 are loosely fitted with guide shafts (not shown) for guiding the optical pickup 4 to move in the seek direction. FIG. 15A shows a guide receiving portion in which the upper surface of the pickup body 26 facing the optical disc 1 is a convex curved surface at least in the optical disc circumferential direction.
[0063]
FIG. 15B shows a case where the upper surface of the pickup main body 26 facing the optical disk 1 is covered with a convex curved cover body 27 except for the light incident / exiting portion of the objective lens 7. The upper surface of the cover body 27 and the upper surface of the objective lens 7 are flush with each other.
[0064]
FIG. 15 (c) has an opening 28a corresponding to the light incident / exiting portion of the objective lens 7 and covers the upper surface of the pickup body 26 facing the optical disk 1 with the cover 28 having a convex curved surface. An opening 28 a of the cover body 28 is closed with a transparent member 29.
[0065]
In the present embodiment, the objective lens 7 faces the optical disc 1 with an appropriate gap. As a reference example, what has a focusing (Fo) and tracking (Tr) control structure will be described, for example, FIG. , FIG. 17, or FIG. 18 and FIG.
[0066]
The optical pickup shown in the plan view of FIG. 16 and the front view of FIG. 17 has a moving coil type biaxial actuator structure using a known four wire 31. The objective lens 7 is fixed to a lens housing 32 of the actuator, and the lens housing 32 is fixed to the support column 33 by four parallel wires 31. Further, a focus coil 35 and a track coil 36 are fixed to the lens housing 32, and a current is passed through the coils 35 and 36 in a magnetic field generated between two magnets 38 fixed to the yoke 37. As a result, it is driven in the arrow directions Tr and Fo. In the figure, 39 indicates an actuator base.
[0067]
In the configuration of the present embodiment using the stabilizing member, the driving stroke in the focus direction is extremely small. Therefore, such a conventional actuator configuration is not necessary and can be simplified.
[0068]
In the optical pickup shown in the plan view of FIG. 18 and the front view of FIG. 19, the track coil 36, the magnet 38, and the yoke 37 are the same as those in FIG. 16 and FIG. The rotation shaft 40 is constituted by a piezoelectric element, and the entire lens housing 34 is driven in the focus direction Fo of the arrow by an applied voltage. The driving stroke of a normal piezo piezoelectric element is about several tens of μm, which is sufficient for the main driving.
[0069]
Thus, by using the piezoelectric element, the actuator is simplified and reduced in size. Furthermore, since it is strong against an external force (air pressure) in the focus direction Fo, the Bernoulli effect with the optical disc 1 is stabilized, and surface blurring is reduced.
[0070]
FIG. 20 is a schematic configuration diagram illustrating an example of the optical pickup of the present embodiment, in which focus control is performed by driving the collimating lens 22 in the optical axis direction (arrow a direction) by an actuator 42. Thus, the actuator 43 on the objective lens 7 side may be a single-axis actuator that drives only in the track direction (arrow b direction). Therefore, for example, a simple actuator similar to the actuator shown in FIGS. 18 and 19 can be used. Of course, the material of the rotating shaft need not be a piezoelectric element.
[0071]
FIG. 21 is a schematic configuration diagram showing an example of the optical pickup according to the present embodiment. The difference from the configuration of FIG. 20 is that one of the expander lenses 44 and 45 is driven by the actuator 46 in the optical axis direction (arrow a direction). Thus, the focus control is performed. As described above, the driving accuracy can be made rougher than when the collimating lens 22 is driven in the direction a.
[0072]
FIG. 22 is a schematic configuration diagram showing an example of the optical pickup according to the present embodiment. The difference from the configuration of FIG. 20 is a configuration in which a liquid crystal element 47 having concentric transparent divided electrodes is used as a focus actuator. By controlling the voltage applied to the divided electrodes to control the focus of the focused spot of the objective lens 7, the apparatus can be miniaturized.
[0073]
The configuration example of FIG. 23 is similar to the configuration example of FIG. 20, but the objective lens 7 is fixed, and the collimating lens 22 is moved by the actuator 48 in the optical axis direction (arrow a direction) and the optical axis vertical direction (arrow b direction). ) To perform focus control and track control. Since the objective lens 7 is completely fixed, the positional relationship with the stabilizing member 5 can also be fixed, and it is possible to stabilize surface blurring or to easily reduce the weight of the seek mechanism.
[0074]
The configuration example of FIG. 24 is similar to the configuration example of FIG. 21, but the objective lens 7 is fixed, and one of the expander lenses 44 and 45 is moved by the actuator 49 in the optical axis direction (arrow a direction) and the optical axis vertical. It is configured to perform focus control and track control by driving in the direction (arrow b direction). Usually, an afocal expander lens is more resistant to positional fluctuations than a collimating lens, so that driving accuracy can be made rough.
[0075]
The configuration example of FIG. 25 is similar to the configuration example of FIG. 21, but the objective lens 7 is fixed and the liquid crystal element 47 having concentric transparent divided electrodes is used as a focus actuator, and the rising mirror 23 is used instead. A galvanometer mirror 50 is installed, and the galvanometer mirror 50 is used as a track actuator.
[0076]
By rotating the galvanometer mirror 50 in the arrow direction b in conjunction with the track signal, the track control of the light spot condensed on the disk surface is performed. Since the galvanometer mirror 50 can be disposed in the installation space of the rising mirror 23 in FIG. 22, the apparatus can be downsized.
[0077]
The above-described actuator of the objective lens 7 has a single-axis drive (track direction drive) configuration, or an optical pickup with the objective lens 7 fixed, the actuator is small and light. The benefits of Further, even in the configuration examples shown in FIGS. 16 to 19, the focus stroke can be small, so that the actuator can also be reduced in size and weight.
[0078]
FIG. 26 is a schematic configuration diagram showing an example of the optical pickup of the present embodiment. For example, the optical system in the optical pickup 4 of the configuration example shown in FIG. 25 is a separation optical system. 22, the liquid crystal element 47 is configured as a fixed optical system A, and the galvanometer mirror 50 and the objective lens 7 are configured as a moving optical system B, which are separated from each other. The moving optical system B is driven in the seek direction C indicated by the arrow in accordance with the seek control operation. By doing so, the volume or weight of the moving optical system B becomes smaller than that of a normal optical system integrated type, so that high-speed seek is possible.
[0079]
Next, the present invention will be described more specifically based on examples.
[0080]
(Example 1)
In Example 1, the main stabilizing member 5 and the optical pickup 4 having the configuration in the embodiment shown in FIG. 2 are employed in the optical disc apparatus shown in FIGS. R is the optical pickup flow line in the disk radial direction.
[0081]
The optical pickup 4 has a spherical shape with a radius of curvature of 200 mm, excluding the objective lens 7, and a shape in which the objective lens 7 having a surface diameter of 3 mm, a surface curvature radius of 15 mm, and an NA of 0.85 is embedded in the center. The average radius of curvature of the surface of No. 4 in the disk radial direction was 180 mm. The size of the optical disk facing surface of the optical pickup 4 was 15 mm in diameter. Further, the focus servo operation of the optical pickup 4 is performed by a movable expander lens disposed between the objective lens 7 and the laser light source, and the focal position of the objective lens 7 is driven with reference to the work distance of the optical pickup 4 by driving. It was made to swing dynamically within an operating range of ± 10 μm. The work distance of the pickup 4 was 100 μm.
[0082]
The auxiliary stabilizing member 6 has a columnar shape with a diameter of 40 mm with a surface facing the optical disc (diameter 120 mm) 1 having a radius of curvature of 200 mm, and the main stabilizing member 5 has a surface facing the optical disc 1 with a radius of curvature of 50 mm. A cylindrical shape with a diameter of 15 mm was used. Further, the auxiliary stabilizing member 6 is disposed at a 90 degree position on the upstream and downstream sides of the disk rotation direction with respect to the main stabilizing member 5 so that the center of the disk facing surface is positioned at a radius of 45 mm of the optical disk 1. Although not shown, the main stabilization member 5 is provided with a moving mechanism in the disk radial direction and a position control mechanism in the disk rotation axis direction, and the auxiliary stabilization member 6 is provided with a position control mechanism in the disk rotation axis direction. And a tilt control mechanism in the disc radial direction and the disc circumferential direction. The rotation center in the tilt angle control of the tilt control mechanism of the auxiliary stabilizing member 6 is the center position of the working surface of the auxiliary stabilizing member.
[0083]
In Example 1, a case where a polycarbonate sheet having a thickness of 120 mm and a thickness of 75 μm is used as a disk substrate will be described. In preparing the disk, first, a groove having a stamper pitch of 0.6 μm and a width of 0.3 μm is transferred to the sheet by thermal transfer, and then the sheet / Ag reflection layer 120 nm / (ZrO) by sputtering. ₂ -Y ₂ O ₃ ) -SiO ₂ 7nm / AgInSbTeGe 10nm / ZnS-SiO ₂ 25nm / Si ₃ N ₄ Films were formed in the order of 10 nm. The information recording area was set in a range from an inner diameter of 40 mm to an outer diameter of 118 mm (radius 20 mm to 58 mm). Thereafter, a UV resin was spin-coated and cured by ultraviolet irradiation to form a transparent protective film having a thickness of 5 μm. Further, a hard coat having a thickness of 10 μm was applied to the opposite surface. A hub 2 having an outer diameter of 30 mm, an inner diameter of 15 mm, and a thickness of 0.3 mm was attached to the center of the disk. The finished state of the disk was slightly warped to the hard coat side.
[0084]
The optical disk 1 was rotated at a disk rotational speed of 15 m / sec, and the auxiliary stabilizing member 6 was disposed at a predetermined position. After that, the main stabilizing member 5 is arranged so that the apex of its working surface is in the vicinity of the disk reference surface, and then the optical pickup 4 is arranged on the opposite side between the main stabilizing member 5 and the optical disk 1, The gap amount with respect to the main stabilizing member 5 was adjusted so that the in-focus position of the optical pickup 4 was near the recording layer of the optical disc 1. Here, finally, the gap amount at the closest position was arranged at a position where it was approximately 200 μm. The main stabilizing member 5 and the optical pickup 4 are scanned while keeping their relative positions along the radial direction of the disk. In this state, a focus servo operation by the optical pickup 4 was performed, and a focus servo error at this time, that is, a signal corresponding to a disc surface shake that could not be suppressed even by the focus servo operation was detected and converted to a disc surface shake amount.
[0085]
Here, the auxiliary stabilizing member 6 is 1 degree in the direction in which the outer peripheral part is brought close to the optical pickup 4 with respect to the disk radial direction, and 0.7 degree in the clockwise direction toward the disk center with respect to the disk circumferential direction. It was tilted and placed at a position where it was pushed in by 0.5 mm with reference to the disk reference surface. The disk reference surface here is a disk surface on the side of the main stabilizing member 5 when the disk is assumed to be ideally flat, and the auxiliary stabilizing member 6 that determines the pushing amount. The reference position was the center position for tilt angle control.
[0086]
(Example 2)
In Example 2, based on the configuration of Example 1, the configurations of the main stabilizing member and the optical pickup were changed as in the embodiment shown in FIG.
[0087]
The surface of the optical pickup 4 except the objective lens 7 is a spherical surface having a curvature radius of 100 mm, and the objective lens 7 having a surface diameter of 3 mm, a surface curvature radius of 15 mm, and an NA of 0.85 is embedded in the center. The average radius of curvature of the surface of No. 4 in the disk radial direction was 90 mm. Further, the size of the optical disc facing surface of the optical pickup 4 was set to 30 mm in diameter. Further, the focus servo operation of the optical pickup 4 is performed by a movable expander lens arranged between the objective lens and the laser light source, and the drive position drives the focal position of the objective lens 7 to ± 10 μm with respect to the work distance of the optical pickup 4. Enabled to swing dynamically in the operating range. The work distance of the pickup 4 was 100 μm.
[0088]
The auxiliary stabilizing member 6 has the same shape as in Example 1, and the main stabilizing member 5 has a columnar shape with a diameter of 10 mm with a radius of curvature of 90 mm on the surface facing the optical disc 1. The arrangement of the auxiliary stabilizing member 6 was the same as in Example 1. Although not shown, as in the first embodiment, the main stabilizing member 5 is provided with a moving mechanism in the disk radial direction and a position control mechanism in the disk rotation axis direction, and the auxiliary stabilizing member 6 has a disk. A position control mechanism in the rotation axis direction and a tilt control mechanism in the disk radial direction and the disk circumferential direction are provided. The rotation center in the tilt angle control of the tilt control mechanism of the auxiliary stabilizing member 6 is also set to the center position of the working surface of the auxiliary stabilizing member, as in the first embodiment.
[0089]
The same optical disk 1 as in Example 1 was used.
[0090]
The disk rotation speed was set in the same manner as in Example 1, and the arrangement positions of the main stabilizing member 5, the auxiliary stabilizing member 6, and the optical pickup 4 were adjusted by the same adjusting method. By this adjustment, the main stabilizing member 5 and the auxiliary stabilizing member 6 are finally disposed at a position where the gap amount at the closest position is approximately 200 μm. In this state, a focus servo error was detected in the same manner as in Example 1, and converted into a disc surface shake (a surface shake amount that the focus servo cannot follow).
[0091]
(Example 3)
In Example 3, on the basis of the configuration of Example 1, the configuration of the main stabilization member 5 and the optical pickup 4 was changed as in the embodiment shown in FIG.
[0092]
The optical pickup 4 has a spherical shape with a radius of curvature of 200 mm, excluding the objective lens 7, and a shape in which the objective lens 7 having a surface diameter of 5 mm, a surface curvature radius of 15 mm, and an NA of 0.85 is embedded in the center. The average radius of curvature of the surface of No. 4 in the disk radial direction was 180 mm. Further, the size of the optical disc facing surface of the optical pickup 4 was set to 30 mm in diameter. Further, the focus servo operation of the optical pickup 4 is performed by a movable expander lens disposed between the objective lens 7 and the laser light source, and the focal position of the objective lens 7 is driven with reference to the work distance of the optical pickup 4 by driving. It was made to swing dynamically within an operating range of ± 10 μm. The work distance of the pickup 4 was 300 μm.
[0093]
The auxiliary stabilizing member 6 has the same shape as in Example 1, and the main stabilizing member 5 has a columnar shape with a diameter of 10 mm with a surface facing the optical disc 1 having a radius of curvature of 50 mm. The arrangement of the auxiliary stabilizing member 6 was the same as in Example 1. Although not shown, as in the first embodiment, the main stabilizing member 5 is provided with a moving mechanism in the disk radial direction and a position control mechanism in the disk rotation axis direction, and the auxiliary stabilizing member 6 has a disk. A position control mechanism in the rotation axis direction and a tilt control mechanism in the disk radial direction and the disk circumferential direction are provided. The rotation center in the tilt angle control of the tilt control mechanism of the auxiliary stabilizing member 6 is also set to the center position of the working surface of the auxiliary stabilizing member 6 as in the first embodiment.
[0094]
The same optical disk 1 as in Example 1 was used.
[0095]
The disk rotation speed was set in the same manner as in Example 1, and the arrangement positions of the main stabilizing member 5, the auxiliary stabilizing member 6, and the optical pickup 4 were adjusted by the same adjusting method. By this adjustment, the main stabilizing member 5 and the auxiliary stabilizing member 6 were finally disposed at a position where the gap amount at the closest position was approximately 400 μm. In this state, a focus servo error was detected in the same manner as in Example 1, and converted into a disc surface shake (a surface shake amount that the focus servo cannot follow).
[0096]
(Example 4)
In Example 4, the configuration of the main stabilization member 5 and the optical pickup 4 of Embodiment 3 shown in FIG. 5 is adopted in the optical disk apparatus shown in FIGS.
[0097]
The optical pickup 4 has a spherical shape with a radius of curvature of 200 mm, excluding the objective lens 7, and a shape in which the objective lens 7 having a surface diameter of 5 mm, a surface curvature radius of 15 mm, and an NA of 0.85 is embedded in the center. The average radius of curvature of the surface of No. 4 in the disk radial direction was 180 mm. Further, the size of the optical disc facing surface of the optical pickup 4 was set to 30 mm in diameter. Further, the focus servo operation of the optical pickup 4 is performed by a movable expander lens arranged between the objective lens 7 and the laser light source, and the focus position of the objective lens 7 is determined based on the work distance position of the optical pickup 4 by driving the focus lens. Thus, it was allowed to swing dynamically within an operating range of ± 10 μm. The work distance of the pickup 4 was 300 μm.
[0098]
The auxiliary stabilizing member 6 has the same shape as that of the first embodiment. The main stabilizing member 5 is configured to extend in the disk radial direction, and continuously changes the radius of curvature of the disk circumferential direction on the surface facing the optical disk 1 and the effective area width from the disk inner periphery to the outer periphery. The configuration. As the actual shape parameters, the radius of curvature is 80 mm at the position of the disk radius 25 mm, 50 mm at the position of the radius 60 mm, and the effective area width is 25 mm at the position of the disk radius 25 mm and 10 mm at the position of the radius 60 mm. did.
[0099]
Although not shown, as in the first embodiment, the main stabilization member 5 is provided with a position control mechanism in the disk rotation axis direction, and the auxiliary stabilization member 6 is provided with a position control mechanism in the disk rotation axis direction. And a tilt control mechanism in the disc radial direction and the disc circumferential direction. The rotation center in the tilt angle control of the tilt control mechanism of the auxiliary stabilizing member 6 is also set to the center position of the working surface of the auxiliary stabilizing member 6 as in the first embodiment.
[0100]
The same optical disk 1 as in Example 1 was used.
[0101]
The optical disk 1 was rotated at a disk rotational speed of 15 m / sec, and the auxiliary stabilizing member 6 was disposed at a predetermined position. Thereafter, the straight line connecting the apexes in the extending direction of the working surface of the main stabilizing member 5 is arranged in the disc radial direction and in the vicinity of the disc reference surface. Thereafter, the optical pickup 4 is placed in the main stabilizing member. 5 and the optical disc 1 are arranged on the opposite side. Thereafter, the gap amount between the main stabilizing member 5 and the optical pickup 4 was adjusted so that the in-focus position of the optical pickup 4 was present in the vicinity of the recording layer of the optical disc 1. Here, finally, the gap amount at the closest position is arranged at a position where the gap amount is approximately 400 μm. In this state, a focus servo operation by the optical pickup 4 was performed, and a focus servo error at this time, that is, a signal corresponding to a disc surface shake that could not be suppressed by the focus servo operation was detected and converted into a disc surface shake amount.
[0102]
Here, the auxiliary stabilizing member 6 is 1 degree in the direction in which the outer peripheral part is brought close to the optical pickup 4 with respect to the disk radial direction, and 0.7 degree in the clockwise direction toward the disk center with respect to the disk circumferential direction. It was tilted and placed at a position where it was pushed in by 0.5 mm with reference to the disk reference surface. The disk reference surface here is a disk surface on the side of the main stabilizing member 5 when the disk is assumed to be ideally flat, and the auxiliary stabilizing member 6 that determines the pushing amount. The reference position was the center position for tilt angle control.
[0103]
(Comparative example)
In this comparative example, in the optical disk apparatus shown in FIGS. 7 and 8, the main stabilizing member 5 and the optical pickup 4 are configured as shown in FIG.
[0104]
The optical pickup 4 has a general configuration in which the objective lens 7 is displaced in the disc rotation axis direction to perform a focus servo operation, and the operation range is ± 500 μm. It should be noted that the reference position of the surface of the objective lens 7 in this operation was a position protruding approximately 500 μm from the housing surface of the optical pickup 4. The shape of the surface of the optical pickup 4 excluding the objective lens 7 is a plane, and the objective lens 7 has a surface diameter of 3 mm, a surface curvature radius of 15 mm, and NA of 0.85. In addition, the size of the optical disc facing surface of the optical pickup 4 was set to 15 mm in diameter, and the work discance of the optical pickup 4 was positioned 100 μm from the surface of the objective lens 7.
[0105]
The auxiliary stabilizing member 6 has the same shape as that of Example 1, and the main stabilizing member 5 has a columnar shape with a diameter of 25 mm and a surface facing the optical disk 1 with a radius of curvature of 50 mm. The arrangement of the auxiliary stabilizing member 6 was the same as in Example 1. Although not shown, as in the first embodiment, the main stabilizing member 5 is provided with a moving mechanism in the disk radial direction and a position control mechanism in the disk rotation axis direction, and the auxiliary stabilizing member 6 has a disk. A position control mechanism in the rotation axis direction and a tilt control mechanism in the disk radial direction and the disk circumferential direction are provided. The rotation center in the tilt angle control of the tilt control mechanism of the auxiliary stabilizing member 6 is also set to the center position of the working surface of the auxiliary stabilizing member 6 as in the first embodiment.
[0106]
The same optical disk 1 as in Example 1 was used.
[0107]
The optical disk 1 was rotated at a disk rotational speed of 15 m / sec, and the auxiliary stabilizing member 6 was disposed at a predetermined position. After that, the main stabilizing member 5 is arranged so that the apex of its working surface is in the vicinity of the disk reference surface, and then the optical pickup 4 is arranged on the opposite side between the main stabilizing member 5 and the optical disk 1, The optical pickup 4 was adjusted so that the in-focus position was located close to the disk surface and in the vicinity of the recording layer of the optical disk 1. The main stabilizing member 5 and the optical pickup 4 are scanned while keeping their relative positions along the radial direction of the disk. In this state, a focus servo operation by the optical pickup 4 was performed, and a focus servo error at this time, that is, a signal corresponding to a disc surface shake that could not be suppressed by the focus servo operation was detected and converted into a disc surface shake amount.
[0108]
Here, the auxiliary stabilizing member 6 is 1 degree in the direction in which the outer peripheral part is brought close to the optical pickup 4 with respect to the disk radial direction, and 0.7 degree in the clockwise direction toward the disk center with respect to the disk circumferential direction. It was tilted and placed at a position where it was pushed in by 0.5 mm with reference to the disk reference surface. The disk reference surface here is a disk surface on the side of the main stabilizing member 5 when the disk is assumed to be ideally flat, and the auxiliary stabilizing member 6 that determines the pushing amount. The reference position was the center position for tilt angle control.
[0109]
In the comparative example, when the optical pickup 4 is brought close to the disk surface up to the in-focus reference position, the shape of the upper surface of the optical pickup 4 in which the objective lens 7 has a protruding shape is an aerodynamic that works on the optical disk 1. It acted as a factor that disturbs the strong force and increased the disc surface wobbling. In addition to this, the vibration of the surface of the objective lens 7 accompanying the focus servo operation has an adverse effect on the stabilization of the disc surface shake, and the disc surface shake has further increased. These effects appear especially for surface blur components of several hundred Hz or higher, and include vibration components exceeding the narrow defocus margin (± 0.1 μm in this comparative example) required for high NA recording. It was. As a result, the recording / reproducing characteristics have deteriorated.
[0110]
On the other hand, in each of the above-described embodiments, the factor causing the irregular shape of the surface of the optical pickup 4 seen in the comparative example is removed, and the vibration of the objective lens 7 caused by the focus servo operation is removed, thereby removing the optical pickup. Even when 4 was placed close to the optical disc 1, a very effective disc surface vibration control effect could be obtained. By this effect, a narrow defocus margin (± 0.1 μm in this embodiment) required for high NA recording can be satisfied, and good recording / reproducing characteristics can be realized.
[0111]
In each example, the gap amount Dg between the main stabilizing member 5 and the optical disc 1 and the gap amount Dp between the optical pickup 4 and the optical disc 1 are as follows.
[0112]
Example 1 Dg: ˜2 μm Dp: ˜100 μm (similar to work distance of optical pickup)
Example 2 Dg: ˜2 μm Dp: ˜100 μm (similar to work distance of optical pickup)
Example 3 Dg: ˜2 μm Dp: ˜300 μm (similar to work distance of optical pickup)
Example 4 Dg: ˜2 μm Dp: ˜300 μm (similar to work distance of optical pickup)
Dp is set near the work distance of the optical pickup 4 and Dg can be reduced. As described above, the Dp is set in the vicinity of the work distance of the optical pickup 4 and the Dg is reduced to improve the effect of suppressing the disc surface blur of the main stabilizing member 5. It was a factor in realizing the reproduction characteristics.
[0113]
As described above, in the present embodiment and this example, in the configuration of the main stabilizing member and the auxiliary stabilizing member that cause the Bernoulli effect, the aerodynamic acting force by the auxiliary stabilizing member is optimized, and recording is performed. It is possible to provide a recording / reproducing apparatus capable of realizing good disk surface fluctuation reduction at the reproducing position.
[0114]
【The invention's effect】
As described above, according to the recording / reproducing apparatus and the control adjustment method thereof according to the present invention, even when an optical pickup having a small work distance is used as the recording / reproducing means, the surface of the objective lens with respect to the recording disk is By fixing the gap amount at the closest position without changing, the aerodynamic force acting on the recording disk by the recording / reproducing means and the stabilizing member can be kept constant. In addition, the disk surface shake can be effectively reduced.
[Brief description of the drawings]
FIG. 1 is a plan view of an essential part for explaining Embodiment 1 of a recording / reproducing apparatus of the present invention.
FIG. 2 is an explanatory diagram enlarging a main part in the first embodiment.
FIG. 3 is an enlarged explanatory view showing a relationship between a radius of curvature approximate to a circle and the surface shape of the optical pickup in the first embodiment.
FIG. 4 is a cross-sectional view of a main part for explaining Embodiment 2 of the recording / reproducing apparatus of the present invention.
FIG. 5 is a cross-sectional view of a main part for explaining Embodiment 3 of the recording / reproducing apparatus of the present invention.
FIG. 6 is an explanatory diagram relating to the stabilization phenomenon of the optical disc of the present invention and an adjustment method thereof
FIG. 7 is a plan view for explaining the relationship between the main stabilizing member and the auxiliary stabilizing member in the recording / reproducing apparatus according to the embodiment.
8 is a front view of the recording / reproducing apparatus in FIG. 7. FIG.
FIG. 9 is a plan view for explaining another relationship between the main stabilizing member and the auxiliary stabilizing member in the recording / reproducing apparatus according to the embodiment.
10 is a front view of the recording / reproducing apparatus in FIG. 9. FIG.
FIG. 11 is a plan view for explaining the relationship between another main stabilizing member and an auxiliary stabilizing member in the recording / reproducing apparatus according to the embodiment.
12 is a front view of the recording / reproducing apparatus in FIG.
FIG. 13 is a schematic configuration diagram of an optical pickup in the present embodiment.
FIG. 14 is an explanatory diagram of a hologram unit in the embodiment of FIG.
FIGS. 15A to 15C are explanatory views of the outer shape of an optical pickup according to the present embodiment.
FIG. 16 is a plan view showing a reference example for explaining the present embodiment;
FIG. 17 is a front view of the reference example of FIG.
FIG. 18 is a plan view of another reference example for explaining the present embodiment;
FIG. 19 is a front view of the reference example of FIG.
FIG. 20 is a schematic configuration diagram of another example of the optical pickup in the embodiment.
FIG. 21 is a schematic configuration diagram of another example of the optical pickup in the present embodiment.
FIG. 22 is a schematic configuration diagram of another example of the optical pickup in the present embodiment.
FIG. 23 is a schematic configuration diagram of an optical pickup similar to the embodiment of FIG.
FIG. 24 is a schematic configuration diagram of an optical pickup similar to the embodiment of FIG.
25 is a schematic configuration diagram of another example of an optical pickup similar to the embodiment of FIG.
FIG. 26 is a schematic configuration diagram of another example of the optical pickup in the present embodiment.
FIG. 27 is an explanatory diagram for explaining a main part in a comparative example with the embodiment of the present invention.
[Explanation of symbols]
1 Optical disc
2 Hub
3 Spindle motor
4 Optical pickup
4a Optical pickup housing
5 Main stabilizer
6 Auxiliary stabilizer
7 Objective lens
9 Focus servo operation system
10 Approximate circle in the disk radial direction on the pickup surface
11 Stabilization surface on the pickup side
Dg, Dp, Dgp Gap amount
Rp, Rp1, Rp2, Rg Curvature radius
Wg, Wp Effective area width

Claims (8)

A stabilizing member that rotates a flexible recording disk and uses the Bernoulli effect to suppress at least the recording / reproducing position near the recording / reproducing position, and a working surface of a main Bernoulli effect of the recording disk In a recording / reproducing apparatus comprising recording / reproducing means provided with an objective lens for condensing a light beam onto the optical information recording medium in order to perform recording and / or reproduction on the opposite side,
The gap amount at the closest position of the surface facing the recording disk of the objective lens and the gap amount at the closest position of the surface facing the recording disk of the stabilizing member are at least at the time of recording / reproducing. A recording / reproducing apparatus characterized by being fixed. The objective lens is fixed to the casing of the recording / reproducing means, and a focus servo mechanism is provided in an optical system constituting the recording / reproducing means at a part different from the installation position of the objective lens. The recording / reproducing apparatus according to claim 1. 3. The recording / reproducing apparatus according to claim 1, wherein a main shape in a disk circumferential direction on a surface including the objective lens facing the recording disk of the recording / reproducing means is a convex curved surface. 3. The recording / reproducing apparatus according to claim 1, wherein a main surface in a disk circumferential direction on a surface of the stabilizing member facing the recording disk is a convex curved surface. The radius of curvature of a curve obtained by circularly approximating the shape in the circumferential direction of the disk on the surface including the objective lens facing the recording disk of the recording / reproducing means is the disk circumference on the surface of the stabilizing member facing the recording disk. 5. The recording / reproducing apparatus according to claim 1, wherein the directional shape is larger than the radius of curvature of a curve that approximates a circle. The width in the disk circumferential direction on the surface of the recording / reproducing means facing the recording disk is made larger than the width in the disk circumferential direction of the surface of the stabilizing member facing the recording disk. The recording / reproducing apparatus according to claim 1. The radius of curvature of a curve obtained by circularly approximating the shape in the circumferential direction of the disk on the surface including the objective lens facing the recording disk of the recording / reproducing means is the circumferential direction of the disk on the surface of the stabilizing member facing the recording disk. The radius of curvature of the recording / reproducing means is larger than the radius of curvature of the curve that approximates the shape of the circle, and the width in the disk circumferential direction of the surface facing the recording disk of the recording / reproducing means is 5. The recording / reproducing apparatus according to claim 1, wherein the recording / reproducing apparatus is larger than a width in a disk circumferential direction. 8. A control adjustment method used in the recording / reproducing apparatus according to claim 1, wherein the recording / reproducing is performed by adjusting the gap amount between the recording / reproducing means and the stabilizing member. A control / adjustment method for a recording / reproducing apparatus, wherein the gap amount between the recording / reproducing means is adjusted to be substantially equal to the actual moving distance of the recording / reproducing means.

Images