JP4443511B2 - Suspension and information recording / reproducing apparatus - Google Patents

Description

  The present invention has a near-field optical head having a near-field light generating element for generating near-field light at the tip, a suspension for recording / reproducing high-density information, and an information recording / reproducing apparatus having the suspension It is about.

  In recent years, the recording density of information within a single recording surface has increased as the capacity of hard disks and the like in computer equipment has increased. For example, in order to increase the recording capacity per unit area of the magnetic disk, it is necessary to increase the surface recording density. However, as the recording density increases, the recording area occupied by one bit on the recording medium decreases. When this bit size is reduced, the energy of 1-bit information is close to that of room temperature, and the recorded information is reversed or lost due to thermal fluctuation, etc. Will occur.

  In the in-plane recording method that has been generally used, the magnetism is recorded so that the direction of magnetization is in the in-plane direction of the recording medium. In this method, the recorded information is lost due to the thermal demagnetization described above. Is likely to occur. Therefore, in order to solve such a problem, a shift is being made to a perpendicular recording method in which a magnetization signal is recorded in a direction perpendicular to the recording medium. This method is a method for recording magnetic information on the principle of bringing a single magnetic pole closer to a recording medium. According to this method, the recording magnetic field is directed substantially perpendicular to the recording film. Information recorded by a perpendicular magnetic field is easy to maintain in energy stability because it is difficult for the N pole and the S pole to form a loop in the recording film surface. Therefore, this perpendicular recording method is more resistant to thermal demagnetization than the in-plane recording method.

  However, recent recording media are required to have a higher density in response to the need to record and reproduce a larger amount and higher density information. For this reason, in order to minimize the influence of adjacent magnetic domains and thermal fluctuations, those having a strong coercive force have begun to be adopted as recording media. For this reason, it is difficult to record information on a recording medium even in the above-described perpendicular recording system.

In order to solve this problem, there is provided a hybrid magnetic recording method in which magnetic domains are locally heated by near-field light to temporarily reduce the coercive force, and writing is performed during that time. This hybrid magnetic recording system is a system that uses near-field light generated by the interaction between a minute region and an optical aperture having a size equal to or smaller than the wavelength of light formed in the near-field optical head. Thus, by using a small optical aperture that exceeds the diffraction limit of light, that is, a near-field light head having a near-field light generating element, the wavelength of light that has been limited in the conventional optical system can be reduced. It is possible to handle the optical information in the region. Therefore, it is possible to achieve a higher recording bit density than conventional optical information recording / reproducing apparatuses.
Note that the near-field light generating element is not limited to the above-described optical micro-aperture, and may be constituted by, for example, a protrusion formed in a nanometer size. This projection can also generate near-field light in the same manner as the optical minute aperture.

  Various types of information recording / reproducing apparatuses based on the hybrid magnetic recording system described above are provided, and as one of them, by supplying light for generating near-field light to the near-field light head, There is known an information recording / reproducing apparatus that generates sufficiently large near-field light from a minute aperture and can achieve reproduction / recording with high resolution, high-speed recording / reproduction, and a high SN ratio (for example, see Patent Document 1).

As shown in FIG. 16, the information recording / reproducing apparatus 50 includes a suspension arm 51 made of a metal material, a gimbal 52 formed at the tip of the suspension arm 51, and the suspension arm 51 via the gimbal 52. And a fixed near-field light head (near-field light head) 53.
The suspension arm 51 is connected to a voice coil motor (not shown) on the base end side, and is movable in the horizontal direction by driving the motor. The gimbal 52 stabilizes the posture so that the near-field optical head 53 is floated at a certain height separated from the surface of the recording medium 54 by a predetermined distance (for example, several tens of nanometers) (flying head technology). The near-field light head 53 has a not-shown minute aperture that generates near-field light, and also has an unillustrated optical coupling part into which a light beam from a laser beam 55 described later is incident.

On the surface of the suspension arm 51, an optical fiber 57 that guides the light beam emitted from the laser 55 through the lens 56 to the gimbal 52 is fixed from the proximal end side to the distal end side. A lens 58 and a mirror 59 for guiding the light beam emitted from the tip to the gimbal 52 are fixed.
A light receiving head 60 is disposed at a position facing the near-field light head 53 with the recording medium 54 interposed therebetween. The light receiving head 60 is fixed to the tip of a suspension arm 61 formed in the same manner as the suspension arm 51. The light receiving head 60 receives scattered light generated as a result of the interaction between the near-field light and the recording medium 54 and receives an electric signal. To the circuit system 62. The circuit system 62 amplifies the electrical signal and generates a reproduction signal of information.

  When information is written on the recording medium 54 by the information recording / reproducing apparatus 50 configured as described above, first, the suspension arm 51 is scanned and moved in the horizontal direction by the voice coil motor to a desired position on the recording medium 54. The near-field light head 53 is moved. At this time, since the near-field light head 53 is fixed to the suspension arm 51 via the gimbal 52, the posture is stabilized corresponding to the undulation of the recording medium 54 rotating at high speed. In other words, the flying head technique floats from the recording medium 54 so as to maintain a certain height. Thereby, the distance between the minute aperture of the near-field optical head 53 and the recording medium 54 is always kept constant.

Next, a light beam is emitted from the laser 55. The emitted light beam enters the optical fiber 57 through the lens 56 and is guided to the tip of the suspension arm 51 through the optical fiber 57. The light beam emitted from the tip of the optical fiber 57 reaches the mirror 59 through the lens 58 and is reflected by the mirror 59 to change its angle. The light flux whose angle has changed enters the near-field optical head 53 with an optical coupling portion and is guided to a minute aperture. Thereby, near-field light is generated in the vicinity of the minute aperture. Due to the near-field light, the recording medium 54 is locally heated and the coercive force is temporarily reduced. As a result, information can be written to the recording medium 54.
When information is reproduced from the recording medium 54, the scattered light generated by the near-field light can be read by the light receiving head 60 as described above.
JP 2001-297463 A

However, the conventional information recording / reproducing apparatus described in Patent Document 1 has the following problems.
That is, since the optical fiber 57 for guiding the light beam for generating near-field light is fixed on the surface of the suspension arm 51 from the base end side to the tip end side, the movement of the suspension arm 51 and the gimbal 52 is obstructed. As a result, the posture of the near-field light head 53 is unstable. That is, the near-field optical head 53 is controlled in posture so as to float at a certain height while corresponding to the undulation of the recording medium rotating at high speed by the movement of the suspension arm 51 and the gimbal 52. However, since the optical fiber 57 is fixed to the surface of the suspension arm 51, the optical fiber 57 is stretched, and the movement of the suspension arm 51 and the gimbal 52 is hindered. For this reason, the distance between the near-field optical head 53 and the recording medium 54 changes, and information may not be recorded or reproduced with high accuracy. Further, not only the optical fiber 57 is stretched, but also the weight of the optical fiber 57 is affected.

  Further, every time the suspension arm 51 is moved by driving the boil coil motor and the recording medium 54 is scanned, the optical fiber 57 becomes a resistance and a windage loss occurs. As a result, the scanning speed is reduced, resulting in performance degradation. In addition, since the resistance is large, the power consumption required for scanning has increased.

  Furthermore, since the suspension arm 51 is made of a metal material to give strength, it has a large weight. In particular, since the weight of the optical fiber 57 is taken into consideration in addition to the weight of the suspension arm 51, it is difficult to reduce the overall weight. Therefore, when an impact or the like is applied from an external force, the energy increases due to its own weight, resulting in poor impact resistance. As a result, the reliability was poor.

  The present invention has been made in view of such circumstances, and its purpose is to accurately control the attitude of the near-field optical head to accurately record and reproduce information and reduce weight. And a data recording / reproducing apparatus having the suspension.

The present invention provides the following means in order to solve the above problems.
The suspension of the present invention is a suspension for generating near-field light by guiding a light beam to a near-field light head having a near-field light generating element, and recording and reproducing information on a recording medium using the near-field light, Formed in a plate shape by a resinous material, a flexible optical waveguide having a tip connected to the near-field optical head to guide the light flux to the near-field optical head, and a sheet-like shape formed from a metallic material, The first and second beams that are sandwiched and fixed from above and below with the optical waveguide sandwiched therebetween, and the near-field optical head are rotated about two axes that are parallel to the surface of the recording medium and orthogonal to each other. Gimbal means for fixing to the tip of the first beam in a free state, and the first beam, the second beam, and the optical waveguide are movable in a direction parallel to the surface of the recording medium It is said And it is characterized in and.

In the suspension according to the present invention, first, scanning is performed by moving both beams and the optical waveguide sandwiched between both beams in a direction parallel to the surface of the recording medium with respect to a rotating recording medium such as an optical disk. Let Thereby, the near-field optical head can be positioned at a desired position on the recording medium. Next, the light beam is guided by the optical waveguide, and is incident on the near-field optical head. By incidence of this light beam, near-field light is generated around the near-field light generating element of the near-field light head. The near-field light generating element is composed of an optical minute aperture or a projection formed in a nanometer size.
The recording medium is locally heated by the near-field light, and the coercivity is temporarily reduced. As a result, information can be recorded and reproduced on the recording medium using the near-field optical head.

Here, the near-field optical head is supported by both beams and the optical waveguide and is pressed against the recording medium side with a predetermined force. At the same time, the near-field optical head receives a flying force under the influence of wind pressure generated by the rotating recording medium. Due to the balance between the two forces, the near-field optical head is in a state of floating at a position spaced apart from the recording medium by a certain distance.
In particular, since the optical waveguide that generates near-field light is formed in a flexible plate shape and is sandwiched between both beams, it is easy to deform following the bending of both beams. That is, it does not stretch like a conventional optical fiber, and it is difficult to hinder the movement of both beams. Therefore, both beams can be reliably bent and the near-field optical head can be stably floated.

Further, the near-field optical head can be twisted about two axes parallel to the surface of the recording medium and orthogonal to each other by the gimbal means, that is, about the two axes. . As a result, even if the recording medium has undulations, changes in wind pressure caused by the undulations can be absorbed by twisting, and the attitude of the near-field optical head when flying can be controlled to a constant attitude. Even in this case, since the optical waveguide is not stretched for the reason described above, the posture can be controlled with high accuracy.
As a result, the flying and posture control of the near-field optical head can be made more stable than before, and information can be recorded and reproduced accurately.

In addition, since the plate-shaped optical waveguide having flexibility is sandwiched between both beams, the optical waveguide itself can be given strength. For this reason, even if the thicknesses of both beams formed of a metal material are made as thin as possible (sheet-like), there is no fear that the overall strength is reduced as compared with the conventional case. Therefore, the weight of both beams can be reduced as much as possible. As a result, the overall weight can be reduced compared to the conventional case, and the weight can be reduced.
Furthermore, since the optical waveguide is sandwiched between the two beams, unlike the conventional optical fiber, when the recording medium is scanned, the wind does not hit directly and it is difficult to cause wind loss. Therefore, it is possible to prevent a decrease in scan speed and improve scan performance.

  As described above, according to the suspension of the present invention, the attitude control of the near-field optical head can be performed with high accuracy, and information can be recorded and reproduced accurately, thereby reducing weight and reducing windage loss. Can do.

  The suspension according to the present invention is the suspension according to the present invention, wherein at least one of the first beam and the second beam is short at an intermediate position between the distal end and the proximal end. An opening extending in the hand direction is formed.

  In the suspension according to the present invention, the cross-sectional area along the short direction (width direction) of at least one of the beams in which the openings are formed is smaller than that in the other regions. Therefore, the beam is easy to bend around the opening in a direction perpendicular to the surface of the recording medium. Therefore, the near-field optical head easily floats and stabilizes when receiving wind pressure from the recording medium. As a result, more accurate information recording / reproduction can be performed.

  In the suspension of the present invention, in the suspension of the present invention, at least one of the first beam and the second beam is constant at an intermediate position between the distal end and the proximal end. It is characterized by being divided into two with a gap in the distance.

  In the suspension according to the present invention, at least one of the beams is divided into two at the intermediate position, so that it is easy to bend in the direction perpendicular to the surface of the recording medium around the divided region. . Therefore, the near-field optical head easily floats and stabilizes when receiving wind pressure from the recording medium. As a result, more accurate information recording / reproduction can be performed.

  The suspension according to the present invention is characterized in that, in the suspension according to the present invention, both the first beam and the second beam are divided into two.

  In the suspension according to the present invention, since both the beams are divided into two, only the plate-like optical waveguide is exposed at this intermediate position. Therefore, the suspension bends only by the elasticity of the flexible optical waveguide without being affected by the rigidity of both beams. Therefore, it becomes easier to bend and the near-field light head can be floated more stably.

  The suspension of the present invention is characterized in that, in the suspension of the present invention, a metal thin film is laminated on the outer surface of the optical waveguide so as to be at least within a divided region where the gap is formed. Is.

  In the suspension according to the present invention, at least in a divided region where both beams are divided, that is, in a region where the optical waveguide is exposed, a metal thin film is laminated on the optical waveguide to reinforce the strength. . Therefore, even if a repeated load accompanying bending deformation is applied to the optical waveguide as the near-field optical head is levitated, it is possible to prevent a reduction in the strength of the optical waveguide as much as possible. Therefore, durability can be improved. Since the thin metal thin film does not affect the flying of the near-field optical head.

  Further, the suspension of the present invention is the suspension of the present invention, wherein the cross-sectional area along the short direction is the cross-sectional area at the other position at the position where the optical waveguide corresponds to the intermediate position of either one of the beams. It is formed so that it may become smaller than this.

  In the suspension according to the present invention, the plate-like optical waveguide is formed to be narrow, for example, so that the cross-sectional area becomes small at the intermediate position. Therefore, the plate-shaped optical waveguide itself is easily bent around this portion. That is, at least one of the beams and the optical waveguide are both easily bent around the intermediate position. Therefore, the near-field light head is more likely to fly.

  An information junction landing / reproducing apparatus according to the present invention includes the suspension according to any one of the present inventions, a light source that causes the light beam to enter the optical waveguide from a proximal end side of the optical waveguide, and the first A motor unit that supports the base end side of the beam, the second beam, and the optical waveguide and moves them in a direction parallel to the surface of the recording medium, and rotates the recording medium in a predetermined direction And a rotation drive unit.

In the information recording / reproducing apparatus according to the present invention, after the recording medium is rotated by the rotation driving unit, both the beam and the optical waveguide are moved by the motor unit to scan the near-field optical head. Then, the near-field optical head is arranged at a desired position on the recording medium. Thereafter, a light beam is incident on the optical waveguide from the light source. Accordingly, various information can be recorded on and reproduced from the recording medium by using the near-field optical head of the suspension.
In particular, since the suspension capable of controlling the attitude of the near-field optical head with high accuracy is provided, information can be recorded and reproduced accurately, and high quality can be achieved. In addition, since the suspension is reduced in weight, even if an impact is applied from the outside, energy can be reduced and impact resistance can be improved. Furthermore, since the suspension is also reduced in windage loss, the scanning speed can be improved and the power consumption can be reduced.

According to the suspension of the present invention, the attitude control of the near-field optical head can be performed with high accuracy to accurately record and reproduce information, and the weight can be reduced and the windage loss can be reduced. .
In addition, according to the information recording / reproducing apparatus of the present invention, since the above-described suspension is provided, it is possible to improve the quality and impact resistance, improve the scanning speed, and reduce the power consumption. Can be planned.

Hereinafter, a first embodiment of a suspension and an information recording / reproducing apparatus according to the present invention will be described with reference to FIGS. 2, 3, 7, and 8, the suspension is turned upside down.
As shown in FIG. 1, the information recording / reproducing apparatus 1 of this embodiment includes an optical signal controller (light source) that causes a light beam to enter the optical waveguide 11 from the base end side of the optical waveguide 11 of the suspension 2 and the suspension 2. ) 3, the lower beam (first beam) 12, the upper beam (second beam) 13, and the base end side of the optical waveguide 11 of the suspension 2 are fixed to the surface of the disk (recording medium) D Actuator motor (motor unit) 4 that scans and moves in parallel XY directions, spindle motor (rotation drive unit) 5 that rotates the disk D in a predetermined direction, and a housing that houses these components inside 6 is provided.

The housing 6 is made of a metal material such as aluminum and has a quadrangular shape when viewed from above, and a recess 6a for accommodating each component is formed inside. Further, a lid (not shown) is detachably fixed to the housing 6 so as to close the opening of the recess 6a.
The spindle motor 5 is attached to substantially the center of the recess 6a, and the disc D is detachably fixed by fitting a center hole into the spindle motor 5. The actuator motor 4 is attached to the corner of the recess 6a. A carriage 8 is attached to the actuator motor 4 via a bearing 7, and the suspension 2 is attached to the tip of the carriage 8. The carriage 8 and the suspension 2 are both movable in the XY directions by driving the actuator motor 4. The carriage 8 and the suspension 2 are avoided from the disk D by driving the actuator motor 4 when the rotation of the disk D is stopped. The optical signal controller 3 is mounted in the recess 6 a so as to be adjacent to the actuator motor 4.

The suspension 2 causes the near-field light head 10 having a near-field light generating element (not shown) to guide the light flux from the optical signal controller 3 to generate near-field light, and use the near-field light to transmit various information to the disk D. Is recorded and reproduced. Note that the near-field light generating element includes, for example, an optical minute aperture, a protrusion formed in a nanometer size, and the like.
That is, as shown in FIGS. 2 and 3, the suspension 2 is formed into a plate shape with a resinous material, and the tip is connected to the near-field optical head 10 so as to guide the light beam to the near-field optical head 10. The optical waveguide 11, the lower beam 12 and the upper beam 13 which are formed in a sheet shape from a metallic material and are sandwiched and fixed from above and below with the optical waveguide 11 sandwiched therebetween, and the near-field optical head 10 are connected to the disk D. Gimbal means for fixing to the tip of the lower beam 12 so as to be rotatable about two axes (X axis, Y axis) parallel to the surface and orthogonal to each other, that is, capable of twisting about the two axes. 14.

As shown in FIG. 4, the optical waveguide 11 is formed in a square shape in a top view from the base end side to the intermediate position, and is formed in a taper shape from the intermediate position to the distal end side to have a plate shape. Furthermore, a narrow band-shaped leading edge portion 11a is formed so as to protrude from the tip.
As shown in FIGS. 4 and 5, the optical waveguide 11 includes a core 11b having a different refractive index and a clad 11c covering the periphery of the core 11b. In addition, the shape of the core 11b is made into the same shape ranging from the base end side to the most advanced part 11a. Further, in order to make the refractive index of the core 11b larger than the refractive index of the clad 11c, it is only necessary to dope germanium when forming the core 11b, and to make the refractive index of the clad 11c smaller than the refractive index of the core 11b. In addition, fluorine may be doped when the clad 11c is formed. In such a case, the light flux is totally reflected in the core 11b and propagates, so that the propagation loss can be reduced.

  Further, as shown in FIG. 4, an opening 11c is formed on the proximal end side of the optical waveguide 11, and is fixed to the tip of the carriage 8 through the opening 11c. Further, the proximal end side of the optical waveguide 11 extends in a narrow band shape so as to proceed on the lower surface of the carriage 8, and is connected to the optical signal controller 3 shown in FIG.

  As shown in FIGS. 2 and 3, the lower beam (one beam) 12 is formed of a thin metal material such as stainless steel and is attached to the lower surface side of the optical waveguide 11. At this time, the lower beam 12 is formed so as to have the same shape from the proximal end side to the distal end side of the optical waveguide 11 so that it can be overlapped in a region excluding the most distal end portion 11 a of the optical waveguide 11. Yes. However, as shown in FIG. 3, the tip of the lower beam 12 is formed so as to further protrude beyond the tip of the optical waveguide 11. An elongated through hole 12a is formed in the longitudinal direction L1 of the lower beam 12 at a position protruding from the tip. The most distal end portion 11a of the optical waveguide 11 is drawn to the lower surface side of the lower beam 12 through the through hole 12a.

  Further, as shown in FIG. 2, the lower beam 12 has an opening 12b extending in the short direction L2 at an intermediate position between the distal end and the proximal end (a boundary position where the top surface changes from a quadrilateral shape to a tapered shape). Is formed. Thereby, the cross-sectional area along the transversal direction L2 is smaller than the cross-sectional area of other parts. As a result, the lower beam 12 is bent around this intermediate position, and is easily bent in the vertical Z direction toward the surface of the disk D. That is, both sides of the opening 12b are hinge portions 12c. Furthermore, an opening 12d having the same size is formed on the base end side of the lower beam 12 so as to overlap the position of the opening 11c of the optical waveguide 11.

As shown in FIG. 3, the upper beam (the other beam) 13 is formed of a thin metal material such as stainless steel like the lower beam 12, and is attached to the upper surface side of the optical waveguide 11. At this time, the upper beam 13 is formed to have the same shape from the proximal end side to the distal end side of the optical waveguide 11 so that it can be overlapped in a region excluding the most distal end portion 11a of the optical waveguide 11. Yes.
Further, the upper beam 13 of this embodiment is divided into two at a middle position between the distal end and the proximal end (a boundary position where the top surface is switched from a quadrilateral shape to a tapered shape) with a gap H of a constant distance. It has been pasted. Thereby, the lower beam 12 and the optical waveguide 11 are easily bent without being affected by the rigidity of the upper beam 13.

  Further, an opening 13 a having the same size is formed on the base end side of the lower beam 12, similarly to the upper beam 13, so as to overlap with the opening 11 c of the optical waveguide 11. That is, as shown in FIG. 7, the opening 12d of the lower beam 12, the opening 13a of the upper beam 13, and the opening 11c of the optical waveguide 11 are all formed at the same position and the same size. Therefore, the carriage 8 can fix the beams 12 and 13 and the optical waveguide 11 at the same time in a state where three layers are stacked.

  Further, as shown in FIGS. 2, 3, and 8, a sheet-like gimbal 20 whose outer shape is formed in a square shape in a top view is attached to the lower surface side of the lower beam 12. The gimbal 20 is formed of a metal material such as aluminum so that the base end side overlaps the distal end sides of the optical waveguide 11 and the upper beam 13 with the lower beam 12 interposed therebetween. A substantially rectangular through hole 20 a is formed on the base end side of the gimbal 20 so as to surround the periphery of the through hole 12 a formed in the lower beam 12. The most distal end portion 11a of the optical waveguide 11 drawn out from the through hole 12a of the lower beam 12 to the lower surface side is further drawn out to the lower surface side of the gimbal 20 through the through hole 20a. The leading-edge portion 11a that is drawn out is connected to the near-field light head 10 that is fixed to a pad portion 20b described later.

Further, as shown in FIG. 8, the gimbal 20 is formed to slightly warp downward from the middle to the tip. The distal end side with the warpage is fixed to the lower beam 12 from the base end side to the vicinity of the middle so as not to contact the lower beam 12.
On the tip side of the floating gimbal 20, a pad portion 20 b whose periphery is wound in a U shape is formed, and the angle is adjusted so that only the pad portion 20 b is parallel to the lower surface of the lower beam 12. Has been. The near-field light head 10 is placed and fixed on the pad portion 20b. That is, the near-field light head 10 is in a state of hanging from the lower beam 12 via the pad portion 20b.

In addition, a protrusion 21 is formed at the tip of the lower beam 12 so as to protrude toward the approximate center of the pad portion 20b and the near-field light head 10. The tip of the projection 21 is rounded. The protrusion 21 is brought into point contact with the surface of the pad portion 20b when the near-field light head 10 floats to the lower beam 12 side by the wind pressure received from the disk D. This rising force is transmitted from the protrusion 21 to the lower beam 12 and acts to bend the lower beam 12.
Further, when the wind pressure in the XY direction is applied to the near-field light head 10 due to the undulation of the disk D, the near-field light head 10 and the pad portion 20b have the X-axis and Y-axis (2 It can be twisted around the axis. Thereby, the wind pressure resulting from the undulation of the disk D can be absorbed, and the posture of the near-field optical head 10 is stabilized.
That is, the gimbal 20 having the protrusion 21 and the pad constitutes the gimbal means 14 described above.

Next, a case where various kinds of information is recorded / reproduced on / from the disk D by the information recording / reproducing apparatus 1 configured as described above will be described below.
First, the spindle motor 5 is driven to rotate the disk D in a predetermined direction. Next, the actuator motor 4 is operated to scan the suspension 2 in the XY directions via the carriage 8. Thereby, the near-field optical head 10 can be positioned at a desired position on the disk D. Next, a light beam is incident on the optical waveguide 11 from the optical signal controller 3. This light beam is guided by the core 11 b of the optical waveguide 11 and enters the near-field optical head 10. Due to the incidence of this light beam, near-field light is generated around the near-field generating element so as to ooze out. The disk D is locally heated by the near-field light, and the coercive force temporarily decreases. As a result, various information on the disk D can be recorded and reproduced using the near-field optical head 10.

Here, the near-field optical head 10 is supported by both beams 12 and 13 and the optical waveguide 11 and is pressed against the disk D side with a predetermined force. At the same time, the near-field optical head 10 receives a flying force under the influence of the wind pressure generated by the rotating disk D. Due to the balance between the two forces, the near-field optical head 10 is in a floating state at a position spaced apart from the disk D by a certain distance.
At this time, the near-field optical head 10 receives the wind pressure and is pushed toward the lower beam 12, so that the pad portion 20 b of the gimbal 20 that fixes the near-field optical head 10 and the projection 21 formed on the lower beam 12 are provided. It will be in the point contact state. The rising force is transmitted to the lower beam 12 via the protrusion 21, and further transmitted to the optical waveguide 11 and the upper beam 13 that are in contact with the lower beam 12. As a result, they are bent in the Z direction perpendicular to the surface of the disk D.

In particular, the optical waveguide 11 of the present embodiment is formed in a flexible plate shape and is sandwiched between both beams 12 and 13, so that it deforms following the bending of both beams 12 and 13. Easy to do. That is, it does not stretch like a conventional optical fiber, and it is difficult to prevent the movement of both beams 12 and 13. Therefore, the near-field light head 10 can be reliably floated.
Further, when the near-field optical head 10 is floated, in this embodiment, an opening 12b is formed at an intermediate position of the lower beam 12 and a hinge portion 12c is provided, and a gap H is formed at the intermediate position of the upper beam 13. Since the space is divided into two, only the lower beam 12 and the optical waveguide 11 are easily bent. Therefore, the near-field light head 10 is more likely to fly. As a result, the near-field optical head 10 can be stably levitated, and information can be recorded and reproduced accurately.

Further, even if the near-field optical head 10 receives wind pressure (wind pressure in the XY direction) generated due to the undulation of the disk D, the pad portion that is in point contact with the tip of the gimbal means 14, that is, the protrusion 21. It can be twisted about the XY axis via 20b. Therefore, the wind pressure caused by the swell can be absorbed, and the posture of the near-field optical head 10 when flying can be controlled to a constant posture. Even in this case, since the optical waveguide 11 is not stretched for the reason described above, the posture can be controlled with high accuracy.
As a result, the flying and posture control of the near-field optical head 10 can be made more stable than before, and information can be recorded and reproduced accurately.

  In addition, since the suspension 2 of the present embodiment has a configuration in which the plate-shaped optical waveguide 11 having flexibility is sandwiched between both beams 12 and 13, the optical waveguide 11 itself can be given strength. Therefore, even if the thicknesses of both beams 12 and 13 formed of a metal material are made as thin as possible (sheet-like), there is no fear that the overall strength is reduced as compared with the conventional case. Therefore, the weight of both beams 12 and 13 can be made as light as possible. As a result, the overall weight can be reduced compared to the conventional case, and the weight can be reduced.

  Further, since the optical waveguide 11 is sandwiched between the beams 12 and 13, unlike the conventional optical fiber, when the disk D is scanned, the wind does not hit directly and it is difficult to cause wind damage. Therefore, it is possible to prevent a decrease in scan speed and improve scan performance.

  Further, according to the information recording / reproducing apparatus 1 of the present embodiment, since the suspension 2 capable of controlling the attitude of the near-field optical head 10 with high accuracy is provided, information can be recorded / reproduced accurately and high quality can be achieved. Can be achieved. In addition, since the suspension 2 is reduced in weight, even if it receives an impact or the like from the outside, the energy can be reduced and the impact resistance can be improved. Furthermore, since the suspension 2 is also reduced in windage loss, the scanning speed can be improved and the power consumption can be reduced.

Next, a second embodiment of the suspension 2 according to the present invention will be described with reference to FIGS. 9 to 11. Note that the same reference numerals in the second embodiment denote the same components as those in the first embodiment, and a description thereof will be omitted.
The difference between the second embodiment and the first embodiment is that, in the first embodiment, only the lower beam 12 and the upper beam 13 are easily bent due to the opening 12b being formed or being divided at an intermediate position. On the other hand, in the suspension 30 of the second embodiment, in addition to this, the optical waveguide 11 itself is easily bent.

That is, in the suspension 30 of this embodiment, as shown in FIGS. 9 to 11, the cross-sectional area along the short direction L <b> 2 is the other position at the position where the optical waveguide 11 corresponds to the intermediate position between the beams 12 and 13. It is formed so as to be smaller than the cross-sectional area that can be placed on the substrate. That is, the optical waveguide 11 has the bending part 31 formed narrowly only in the region crossing the intermediate position. Therefore, the optical waveguide 11 itself is easily bent around the bent portion 31.
According to the suspension 30 having the optical waveguide 11 formed as described above, the near-field optical head 10 is more easily floated and stabilized when receiving the wind pressure from the disk D. As a result, more accurate information recording / reproduction can be performed.

Next, a third embodiment of the suspension according to the present invention will be described with reference to FIG. Note that the same reference numerals in the third embodiment denote the same parts as in the first embodiment, and a description thereof will be omitted.
The difference between the third embodiment and the first embodiment is that, in the first embodiment, only the upper beam 13 is divided into two at the intermediate position, whereas in the suspension 40 of the third embodiment, As shown in FIG. 12, the lower beam 12 and the upper beam 13 are both divided into two with a gap H at an intermediate position.

  According to the suspension 40 configured as described above, both the beams 12 and 13 are divided at the intermediate position, so that only the plate-shaped optical waveguide 11 is exposed at the intermediate position. Therefore, the suspension 40 bends only by the elasticity of the flexible optical waveguide 11 without being affected by the rigidity of the beams 12 and 13. Therefore, the near-field optical head 10 can be floated more easily.

In the case of this embodiment, as shown in FIGS. 13 to 15, a metal thin film 41 is laminated on the outer surface of the optical waveguide 11 so that at least both the beams 12 and 13 fall within the divided region. It doesn't matter. Note that FIG. 13 illustrates a case where the metal thin film 41 is laminated on the outer surface other than the forefront portion 11a.
By doing so, the optical waveguide 11 can be reinforced in a divided region where both beams 12 and 13 are divided, that is, in a region where the optical waveguide 11 is exposed. Therefore, even if a repeated load due to bending deformation acts on the optical waveguide 11 with the flying of the near-field optical head 10, it is possible to prevent a decrease in the strength of the optical waveguide 11 as much as possible. Therefore, durability can be improved. Since the metal thin film 41 is thin, it does not affect the flying of the near-field optical head 10.

  The technical scope of the present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention.

  For example, in the first and second embodiments, an opening is formed in the lower beam at the intermediate position and the upper beam is divided. In the third embodiment, both beams are divided at the intermediate position. It is not limited to the case. For example, openings may be formed in both the lower beam and the upper beam. Moreover, an opening may be formed in only one of the beams, or only one of the beams may be divided into two.

1 is a configuration diagram showing a first embodiment of an information recording / reproducing apparatus having a suspension according to the present invention. It is the perspective view which looked at the suspension shown in Drawing 1 from the lower beam side. It is the perspective view which looked at the suspension shown in Drawing 1 from the upper beam side. It is a perspective view of the optical waveguide which comprises the suspension shown in FIG. FIG. 5 is a cross-sectional view taken along line A-A ′ shown in FIG. 4. It is a cross-sectional arrow B-B 'figure shown in FIG. FIG. 4 is an enlarged sectional view of a base end side of the suspension shown in FIG. 3. FIG. 4 is an enlarged cross-sectional view of the front end side of the suspension shown in FIG. 3. It is a figure which shows 2nd Embodiment of the suspension which concerns on this invention, Comprising: It is the perspective view seen from the lower beam side. FIG. 10 is a perspective view of the suspension shown in FIG. 9 viewed from the upper beam side. It is a perspective view of the optical waveguide which comprises the suspension shown in FIG. It is a figure which shows 3rd Embodiment of the suspension which concerns on this invention, Comprising: It is the perspective view seen from the lower beam side. It is a perspective view which shows the modification of the optical waveguide which comprises the suspension of FIG. It is a cross-sectional arrow C-C 'figure shown in FIG. FIG. 14 is a cross-sectional view E-E ′ shown in FIG. 13. It is a block diagram which shows an example of the conventional information recording / reproducing apparatus.

Explanation of symbols

D disc (recording medium)
L2 Short direction X-axis, Y-axis Two axes parallel to the surface of the recording medium and perpendicular to each other 1 Information recording / reproducing apparatus 2, 30, 40 Suspension 3 Optical signal controller (light source)
4 Actuator motor (motor part)
5 Spindle motor (rotary drive)
10 near-field optical head 11 optical waveguide 12 lower beam (first beam)
12b Aperture 13 Upper beam (second beam)
14 Gimbal means 41 Metal thin film

Claims (7)

A suspension that guides a light beam to a near-field light head having a near-field light generating element to generate near-field light, and records and reproduces information on a recording medium using the near-field light,
A flexible optical waveguide that is formed in a plate shape with a resinous material, has a tip connected to the near-field optical head, and guides the light flux to the near-field optical head;
A first beam and a second beam, which are formed in a sheet shape from a metallic material and are sandwiched and fixed from above and below with the optical waveguide sandwiched therebetween,
Gimbal means for fixing the near-field optical head to the tip of the first beam in a state of being rotatable about two axes parallel to and perpendicular to the surface of the recording medium,
The suspension, wherein the first beam, the second beam, and the optical waveguide are movable in a direction parallel to the surface of the recording medium. The suspension according to claim 1, wherein
At least one of the first beam and the second beam has an opening extending in a short direction at an intermediate position between a distal end and a proximal end. Suspension. The suspension according to claim 1, wherein
At least one of the first beam and the second beam is divided into two at a middle distance between the distal end and the proximal end with a gap of a certain distance. Suspension characterized by. The suspension according to claim 3,
The suspension is characterized in that the first beam and the second beam are both divided into two. The suspension according to claim 4,
A suspension, wherein a metal thin film is laminated on an outer surface of the optical waveguide so as to be at least within a divided region where the gap is formed. In the suspension according to claim 2 or 3,
The optical waveguide is formed so that a cross-sectional area along the short direction is smaller than a cross-sectional area at another position at a position corresponding to an intermediate position of any one of the beams. . The suspension according to any one of claims 1 to 6,
A light source that causes the light beam to enter the optical waveguide from a base end side of the optical waveguide;
A motor unit that supports the first beam, the second beam, and the proximal end of the optical waveguide, and moves them in a direction parallel to the surface of the recording medium;
An information recording / reproducing apparatus comprising: a rotation driving unit configured to rotate the recording medium in a predetermined direction.

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