JP5184065B2 - Recording head and information recording / reproducing apparatus - Google Patents

Description

  The present invention relates to a recording head for recording various types of information using light guided while floating on a rotating magnetic recording medium, and an information recording / reproducing apparatus having the recording head.

  In recent years, in order to cope with a rapid increase in image / moving picture information in an information society, information recording / reproducing apparatuses have been increased in capacity and size. Among these, with respect to information recording / reproducing apparatuses using light, since the recording density depends on the light wavelength, the recording density has been increased by using light having a short wavelength. However, since there is a limit to shortening the wavelength, realization of a recording density independent of the wavelength has been sought for a long time. As one of the methods for realizing this, attention has been paid to a technique for localizing optical energy to a minute spot exceeding the diffraction limit of light by using near-field light.

  In particular, in an information recording / reproducing apparatus using magnetism, it is important to separate and magnetize a minute region on the surface of a magnetic recording medium. However, by irradiating only the minute region with near-field light, the magnetic domain is locally localized. A hybrid magnetic recording system (near-field light assisted magnetic recording system), in which the coercive force is temporarily reduced by heating and writing is performed during that time, is regarded as a promising candidate for the next-generation recording / reproducing principle.

  By adopting this hybrid magnetic recording system, it becomes possible to localize the light spot in a region below the wavelength of light, which has been a limit in the conventional optical system. It is possible to increase the density of recording bits exceeding the above. In this respect, as mentioned above, it is attracting attention as a next-generation technology.

  The near-field light is generated by the near-field light generating element. This near-field light generating element is formed of, for example, an optical minute aperture exceeding the diffraction limit of light, a sharpened metal film, or the like, which is formed in a size equal to or smaller than the wavelength of light. Then, near-field light is generated from the opening tip by irradiating light on the minute aperture, or near-field light is generated by irradiating the tip of the metal film.

  By the way, the near-field light is present in a minute region of several nanometers to several tens of nanometers from the near-field light generating element and does not propagate. In addition, it has a feature of abrupt attenuation depending on the distance from the near-field light generating element. Therefore, in order to generate a minute spot exceeding the diffraction limit by near-field light and to use the minute spot for high-density recording, the near-field light generating element is about several nm to several tens nm from the surface of the magnetic recording medium. It is necessary to be close to the distance.

  On the other hand, the magnetic head in the magnetic recording apparatus operates in a state where it floats a predetermined distance (for example, about 10 nm) from the surface of the magnetic recording medium in order to realize high-density recording. Therefore, the above-described requirements can be satisfied by combining the above-described near-field light generating element with this magnetic head. That is, by incorporating the near-field light generating element into the flying magnetic head, the near-field light generating element can be positioned near the surface of the magnetic recording medium. Therefore, high-density recording can be realized using a micro spot (micro heat source) in which the light spot is localized.

  By the way, some heads that combine the above-described flying technique and the near-field light generating element are already known.

  As one of them, there is known a head that generates near-field light by irradiating light to an optical minute opening provided in the flying head, and records and reproduces information using the near-field light ( Patent Document 1). This head guides light by an optical fiber that is bonded and fixed to the flying head.

In addition, by irradiating the metal film (light scatterer) provided on the flying head with light, near-field light that is strongly localized at the tip of the metal film is generated, and information recording / reproduction is performed using the near-field light. There is also known a head for performing (see Patent Document 2). This head guides light by propagating light in the air. Furthermore, a head that collects light with an optical component such as a lens provided on the flying head to generate near-field light and records and reproduces information using the near-field light is also known (Patent Document). 3) This head also guides light by propagating light in the air.
International Publication No. 00/28536 Pamphlet JP-A-2005-4901 JP 2004-87065 A

  However, the conventional head described above still has the following problems.

  First, a head that floats on a rotating recording medium with a minute interval is required to always float in a stable posture in order to perform stable recording. For this reason, even if the structure that supports the head or the surface facing the recording medium, that is, ABS (Air Bearing Surface), is devised and the recording medium causes surface deflection, the posture changes following this and is stable. Designed to allow levitation.

  On the other hand, in order to perform stable recording using light such as near-field light, it is required to always guide light stably to the head.

  As described above, regarding the flying head using light, it is desired that the two requirements of stable flying and stable light guiding are compatible. However, with the conventional head described above, it has been difficult to satisfy both of these requirements.

  That is, the head described in Patent Document 1 uses an adhesive or the like to firmly fix the optical fiber to the flying head. Therefore, it is excellent in that the light is stably guided to the flying head. However, since the optical fiber is fixed to the flying head, there is a possibility that the posture change of the flying head may be hindered by stretching the optical fiber. For this reason, the flying head is difficult to move following the surface deflection of the recording medium, and the stable flying is inferior.

  The heads described in Patent Documents 2 and 3 are excellent in terms of stable flying because they do not use an optical fiber or the like. However, unlike the case of directly guiding light such as an optical fiber, the light is guided by being propagated in the air. Therefore, it has been difficult to guide light stably. In particular, when the posture of the head is changed, the light incident point is shifted, so that stable light guide becomes more difficult.

  In addition, since it is necessary to arrange an optical component such as a lens and a mirror, a light source, and the like around the head (upward and the like), a compact design cannot be achieved and it is difficult to reduce the size. For this reason, when designing an information recording / reproducing apparatus having this head, a design space is taken up by the amount of the head, and it is difficult to provide a configuration having a plurality of recording media.

  The present invention has been made in consideration of such circumstances, and its purpose is to stably float on a recording medium by a smooth posture change and to stabilize a light beam without being affected by the posture change. Thus, it is possible to provide a recording head capable of guiding light and performing reliable recording and reproduction, and an information recording / reproducing apparatus having the recording head.

  The present invention provides the following means in order to solve the above problems.

  A recording head according to the present invention is a recording head that records and reproduces information on a recording medium that rotates in a certain direction by using spot light generated by condensing an introduced light beam. A head body that is arranged in a state of being floated by a distance and that has spot light generating means for generating spot light on the opposite surface facing the recording medium, and is inserted into the head body via a light guide holder, and the light beam is spotted. A light guide part to be introduced into the light generating means; and a fluid interposed between the light guide part and the inner wall of the light guide part holder, wherein the fluid fills the inside of the light guide part holder. is there.

  In the recording head according to the present invention, the head main body is arranged in a state where it floats a predetermined distance from the surface of the recording medium rotating in a certain direction. When recording is performed here, the light beam is introduced into the spot light generating means of the head body through the light guide. Then, the spot light generation means condenses the introduced light flux and generates spot light. In addition, it is generated on the opposite surface side facing the recording medium. The recording medium is locally heated by the spot light to temporarily reduce the coercive force or change the crystal structure. As a result, it is possible to record and reproduce various information on the recording medium using this spot light.

  By the way, the leading end of the light guide for introducing the luminous flux is inserted into the head body via the light guide holder. Moreover, the light guide unit is slidably held by the light guide unit holder, unlike the conventional adhesive-fixed one. Therefore, the head main body floating on the recording medium can move freely without being hindered by the light guide. That is, in the conventional device, the movement of the head is hindered by the optical fiber tension or the like, but the movement of the head main body is hindered because the light guide is slidably held as described above. There is no fear. Therefore, even if the rotating recording medium causes a surface shake, the posture of the head main body can be changed smoothly following the surface shake. Therefore, the head body can be stably levitated.

  In addition, since the fluid is interposed between the light guide holder and the light guide, the frictional force can be reduced and the light guide can be slid more smoothly. Accordingly, the posture of the head main body can be changed more smoothly, the followability can be improved, and more stable flying can be performed. In addition, since the frictional force between the light guide unit and the light guide unit holder is reduced, durability can also be improved.

  Moreover, since the fluid fills the inside of the light guide and the light guide holder, the movement (flow) of the fluid can be regulated. Therefore, even if the light guide portion slides, the fluid does not flow and leak, and can always be interposed between the light guide portion and the light guide portion holder. Therefore, the effect of the fluid described above can be maintained over a long period of time, and the reliability can be improved.

  In addition, since the light beam is directly introduced into the spot light generating means of the head body using the light guide unit without being propagated in the air, the light beam can be guided stably even if the posture of the head body changes. Can do. Moreover, since the head main body is stably floated on the recording medium as described above, it is easy to control the distance between the facing surface and the recording medium to a predetermined distance. Therefore, the generated spot light can be reliably acted on the recording medium. Therefore, information recording / reproduction can be performed reliably.

  Further, unlike the conventional apparatus in which optical components and light sources are arranged around the head when introducing the light beam, the light beam is directly introduced into the spot light generating means of the head body using the light guide unit. . Therefore, the number of parts can be suppressed, and downsizing can be achieved with a compact design.

  In addition, since the fluid fills the inside of the light guide holder, it also intervenes in the optical path until the light emitted from the light guide reaches the spot light generating means. Therefore, the fluid is guided by adjusting the refractive index of the fluid. It is possible to increase the degree of freedom in optical design that the distance from the light section to the spot light generating means and the light propagation efficiency can be adjusted.

  As described above, according to the recording head according to the present invention, it is possible to achieve both stable levitation and stable light guide, both of which are conventionally difficult. As a result, it is possible to stably float on the recording medium due to a smooth posture change, and to guide the light flux without being influenced by the posture change, and to perform reliable recording and reproduction.

  Further, the recording head according to the present invention is the above-described recording head according to the present invention, wherein the light guide section is a flexible light guide section arranged so as to extend in a direction substantially parallel to the surface of the recording medium. It is held by the light guide holder so as to slide along the longitudinal direction.

  In the recording head according to the present invention, the light guide holder is slid along the longitudinal direction of the light guide arranged so that the light guide holder extends in a direction substantially parallel to the surface of the recording medium. Hold it possible. Here, when the head main body rotates around an axis perpendicular to the surface of the recording medium due to the surface shake of the recording medium (yaw angular motion), the light guide unit tries to follow the posture change of the head main body. So start to turn left or right. However, the light guide is flexible and slidable in the longitudinal direction. Therefore, the light guide portion can be shifted in the longitudinal direction while bending. Therefore, the head body can change its posture without being obstructed by the light guide.

  Similarly, when the head main body rotates about an axis that is horizontal to the surface of the recording medium and orthogonal to the longitudinal direction of the light guide unit (pitch angular motion) due to the influence of surface vibration, the light guide unit is It is possible to shift in the longitudinal direction while bending. Therefore, the head body can change its posture without being obstructed by the light guide. In addition, when the head main body rotates around the axis of the light guide unit due to the influence of surface deflection (roll angular motion), unlike the case described above, the light guide unit does not bend or shift, Only the head body rotates. Therefore, the posture of the head main body can be changed without hindering any movement of the light guide section.

  As described above, the head main body can smoothly change its posture without being obstructed by the light guide portion in any case, and thus stably floats. In particular, the light guide section is displaced in the longitudinal direction, which is the same direction as the direction in which the light beam is introduced into the spot light generating means. Therefore, no matter how the posture of the head body changes, it is possible to always introduce the light beam at the same position with respect to the spot light generating means. That is, the introduction point does not deviate only by changing the distance that the light beam emitted from the light guide portion reaches the spot light generating means.

  Therefore, even if the posture of the head main body changes, spot light can be generated at the same position. However, since the distance between the light guide section and the spot light generating means changes, the spot size changes, and the spot light becomes blurred (increased). However, since the position of the spot light itself does not change as described above, the peak position of the spot light can be made the same position, and the reduction in light efficiency can be minimized. Therefore, the luminous flux can be condensed without waste to produce spot light, and stable recording and reproduction can be performed.

  The recording head according to the present invention is characterized in that, in the recording head according to the present invention, the light guide section is an optical fiber or an optical waveguide.

  In the recording head according to the present invention, an optical fiber or an optical waveguide which is not special and is generally used at low cost can be used as the light guide unit, so that the cost can be reduced and the design can be simplified. it can.

  The recording head according to the present invention is characterized in that, in the recording head according to the present invention, the light guide holder is a groove formed in the head main body and in contact with at least a part of the light guide. is there.

  In the recording head according to the present invention, the light guide portion is fitted into the groove portion, and at least a part thereof is in contact with the groove portion. Therefore, the light guide portion slides stably along the groove portion while being guided by the groove portion. In particular, since the light guide holder can be configured by simply forming the groove in the head body without adding new components, the design can be simplified and the size can be reduced.

  In the recording head according to the present invention, the light guide unit is slidably held by the light guide unit holder in a state where a certain distance from the tip is not in contact with the light guide unit holder. It is characterized by this.

  In the recording head according to the present invention, the tip of the light guide is not in contact with the light guide holder, so that even if the light guide slides within the light guide holder, the tip of the light guide is Since it does not get caught in the holder, the posture of the head body can be changed smoothly.

  In the recording head according to the present invention, the light guide holder includes a light collecting portion for collecting the light beam emitted from the light guide portion, and the fluid is collected after the light beam is emitted from the light guide portion. It is provided in the passage part of the light beam until it is condensed on the part.

  In the recording head according to the present invention, since the light emitted from the light guide unit exists in the optical path until it reaches the light collecting unit, the refractive index of the fluid is adjusted to adjust the refractive index of the fluid. The distance and light propagation efficiency can be adjusted, and the degree of freedom in optical design can be increased.

  An information recording / reproducing apparatus according to the present invention is capable of moving in the direction parallel to the surface of the recording medium and the recording head of the present invention, and about two axes parallel to the surface of the recording medium and perpendicular to each other. A beam that supports the recording head on the tip side while being rotatable about a vertical axis perpendicular to the surface of the medium, a light source that makes the light beam incident on the light guide unit, and a base end side of the beam, An actuator that moves the beam in a direction parallel to the surface of the recording medium, a rotation drive unit that rotates the recording medium in a certain direction, and a control unit that controls the operation of the light source according to the information to be recorded. It is characterized by that.

  In the information recording / reproducing apparatus according to the present invention, after the recording medium is rotated in a certain direction by the rotation driving unit, the recording head is scanned by moving the beam by the actuator. Then, the recording head is arranged at a desired position on the recording medium. At this time, the recording head is in a state of being rotatable about two axes and a vertical axis that are parallel to the surface of the recording medium and orthogonal to each other, that is, the beam can be twisted about the two axes and the vertical axis. It is supported by. Therefore, even if waviness (surface runout) occurs in the recording medium, changes in wind pressure due to waviness or changes in waviness directly transmitted can be absorbed by twisting, and the posture of the recording head can be stabilized. it can.

  Thereafter, the control unit activates the light source. As a result, the recording head can record and reproduce information on the recording medium using the spot light. In particular, since the recording head described above is provided, stable recording and reproduction can be performed without being affected by the surface shake of the recording medium, and high quality can be achieved. Further, since the recording head is miniaturized with a compact design, the information recording / reproducing apparatus itself can be miniaturized.

  According to the recording head of the present invention, it is possible to stably float on a recording medium by a smooth posture change, and to guide a light beam without being influenced by the posture change, thereby performing reliable recording and reproduction. it can.

  Moreover, according to the information recording / reproducing apparatus of the present invention, since the recording head described above is provided, stable recording and reproduction can be performed without being affected by the surface shake of the recording medium, and the quality can be improved. Can be planned.

(Embodiment 1)
A first embodiment according to the present invention will be described below with reference to FIGS.

  As shown in FIG. 1, the information recording / reproducing apparatus 1 of the present embodiment is movable in the XY directions parallel to the recording head 2 and the surface of the disk D (recording medium), parallel to the surface of the disk D and A beam 3 for supporting the recording head 2 on the tip side in a state of being rotatable about two axes (X axis, Y axis) orthogonal to each other and a vertical axis (Z axis) perpendicular to the surface of the disk D; An optical signal controller (light source) 5 for making the light beam L incident on the optical waveguide 4 from the base end side of the light guide portion 4 and the base end side of the beam 3 and supporting the beam 3 on the disk D surface. An actuator 6 that scans and moves in parallel XY directions, a spindle motor (rotation drive unit) 7 that rotates the disk D in a certain direction, and a control unit 8 that controls the operation of the optical signal controller 5 according to information to be recorded. And each of these components And a housing 9 for housing therein.

  The housing 9 is made of a metal material such as aluminum and has a quadrangular shape when viewed from above, and a recess 9a for accommodating each component is formed inside. Further, a lid (not shown) is detachably fixed to the housing 9 so as to close the opening of the recess 9a. The spindle motor 7 is attached to substantially the center of the recess 9a, and the disc D is detachably fixed by fitting a center hole into the spindle motor 7. The actuator 6 is attached to the corner of the recess 9a. A carriage 11 is attached to the actuator 6 via a bearing 10, and a beam 3 is attached to the tip of the carriage 11. The carriage 11 and the beam 3 are both movable in the XY axis direction by driving the actuator 6.

  The carriage 11 and the beam 3 are retracted from the disk D by driving the actuator 6 when the rotation of the disk D is stopped. The recording head 2 and the beam 3 constitute a suspension 12. The optical signal controller 5 is mounted in the recess 9 a so as to be adjacent to the actuator 6. The control unit 8 is attached adjacent to the actuator 6.

  The recording head 2 records and reproduces various types of information on the rotating disk D using spot light S generated by condensing the introduced light beam L. As shown in FIGS. 2 to 5, the recording head 2 is disposed to face the disk D in a state where it floats by a predetermined distance H from the disk surface D1, and has a head body 20 having a facing surface 24a facing the disk surface D1. The tip of the head body 20 is inserted into the head body 20 through the groove 23a and the pot light generating means 21 that is formed on the head body 20 and generates the spot light S from the introduced light beam L and generates it on the facing surface 24a side. The optical waveguide 4 for introducing the light beam L into the spot light generating means 21, the lubricating oil (fluid) W interposed between the groove 23 a and the optical waveguide 4, and the movement of the lubricating oil W are regulated to restrict the movement of the optical waveguide 4. And a recess 23c that keeps the lubricating oil W interposed between the groove portion and the groove portion. The concave portion 23 c is formed on the side surface of the head body 20 where the optical waveguide 4 is inserted. The concave portion 23 c is filled with the lubricating oil W, and the optical waveguide 4 is disposed in the lubricating oil W. With this lubricating oil W, the frictional force between the optical waveguide 4 and the groove 23a is reduced.

  The head main body 20 of this embodiment has a structure in which two substrates are bonded together. That is, the head main body 20 includes an arm side substrate 23 and a medium side substrate 24 which are bonded to each other by bonding or the like. The head body 20 is supported so as to hang from the tip of the beam 3 via the gimbal portion 25 with the facing surface 24a facing the disk D side. The gimbal portion 25 is a component whose movement is restricted so as to be displaced about the X axis, the Y axis, and the Z axis. As a result, the head main body 20 is rotatable about the X axis, the Y axis, and the Z axis perpendicular to the disk surface D1, which are parallel to the disk surface D1 and orthogonal to each other as described above.

  The arm-side substrate 23 constituting the head body 20 is, for example, a Si substrate having a thickness of about 200 μm, and has a V-shaped cross section on the surface facing the medium-side substrate 24 as shown in FIGS. A groove 23a is formed. The groove 23 a is formed so as to be exposed on one side surface of the arm side substrate 23. And the optical waveguide 4 fits in the state which contacted the inner surface of this groove part 23a, and is hold | maintained so that sliding is possible. That is, the groove 23a functions as a light guide holder.

  In each figure, the lubricating oil W is exaggerated as appropriate in order to make the lubricating oil W easy to see. Actually, the film thickness of the lubricating oil W is slight.

  Further, the arm side substrate 23 of the present embodiment is formed with a tapered portion 23b adjacent to the groove portion 23a. The tapered portion 23b is an inclined surface formed such that the distance from the optical waveguide 4 gradually increases as it goes toward the end portion on the distal end side of the optical waveguide 4. Since the taper portion 23b is formed, a certain distance from the tip of the optical waveguide 4 that is slidably held in the groove portion 23a is in a state of floating in the air, with respect to the groove portion 23a and the taper portion 23b. To avoid contact.

  The medium side substrate 24 constituting the head body 20 is, for example, a quartz glass substrate having a thickness of about 200 μm, and the surface on the disk D side is the facing surface 24a as shown in FIGS. . On the facing surface 24a, a convex strip portion 24b is formed which generates a pressure for rising from the viscosity of the air flow generated by the rotating disk D. In this embodiment, the case where the two protruding item | line parts 24b extended along the longitudinal direction are formed so that it may rank with a rail shape is made into the example. However, the present invention is not limited to this case, and the head body 20 is adjusted by adjusting the positive pressure for separating the head body 20 from the disk surface D1 and the negative pressure for attracting the head body 20 to the disk surface D1. Any irregular shape may be used as long as it is designed to float in an optimal state. In addition, the surface of this protruding item | line part 24b is called ABS (Air Bearing Surface).

  The head main body 20 receives a force that rises from the disk surface D1 by the two ridges 24b. Further, the beam 3 bends in the Z direction perpendicular to the disk surface D1, and absorbs the flying force of the head body 20. That is, the head body 20 receives a force that is pressed against the disk surface D1 side by the beam 3 when it floats. Therefore, the head main body 20 floats in a state of being separated from the disk surface D1 by a predetermined distance H as described above due to the balance of both forces. Moreover, since the head body 20 is rotated about the X axis, the Y axis, and the Z axis by the gimbal portion 25, the head body 20 always floats in a stable posture.

  Note that the air flow generated along with the rotation of the disk D flows from the inflow end side (base end side of the beam 3) of the head body 20 and then flows along the ABS, and flows out along the outflow end side (tip side of the beam 3). Is missing.

  Further, as shown in FIG. 10, an aspherical microlens 26 having a diameter of about 80 μm is formed on the medium side substrate 24 on the surface facing the arm side substrate 23. The microlens 26 is a lens that condenses the light beam L reflected by the mirror surface 23d toward a later-described tip 27 formed on the facing surface 24a. Therefore, the microlens 26 is formed at a position facing the tip 27.

  Further, a tip 27 is formed on the facing surface 24a of the medium side substrate 24 as shown in FIGS. The tip 27 is formed integrally with the medium-side substrate 24, and has a quadrangular pyramid shape with four side surfaces 27a and end surfaces 27b. Specifically, the end surface 27b is formed in a square shape in plan view. However, the end surface 27b is not limited to a square shape, and may be formed in a square shape in plan view. For example, it may be rectangular, parallelogram, or trapezoidal. The four side surfaces 27a are in a slope state in which the distance from the side surface 27a facing each other gradually decreases toward the end surface 27b.

  Therefore, when the light beam L condensed by the micro lens 26 is incident on the tip 27, the spot size is gradually reduced and reduced by repeating the reflection on the side surface 27a, and the end surface as the spot light S having a small spot size. 27b is emitted to the outside.

  That is, the mirror surface 23d, the micro lens 26, and the tip 27 described above function as the spot light generating unit 21 described above. The tip 27 is designed so that the height of the end surface 27b from the facing surface 24a is the same as the height of the ridge 24b.

  Further, a light shielding film 28 such as aluminum is formed from the four side surfaces 27a of the tip 27 to the facing surface 24a so as to exclude the end surface 27b. This prevents the light flux L incident on the tip 27 from leaking to the outside from the side surface 27a before reaching the end surface 27b. Thereby, the light beam L can be made into the spot light S without waste, and the loss can be suppressed as much as possible.

  The optical waveguide 4 is a flexible waveguide disposed so as to extend substantially parallel to the disk surface D1, and is a waveguide composed of a core and a clad. The light beam L propagates in the core. As shown in FIGS. 4 and 5, the optical waveguide 4 is slidably held in a form in which the tip is fitted in a groove 23 a formed in the arm side substrate 23. Moreover, the optical waveguide 4 is held so that it can slide in its longitudinal direction. Further, since the optical waveguide 4 is held in a line contact with the groove 23a, it is restricted so as not to move in directions other than the longitudinal direction.

  Although the optical waveguide 4 is flexible, it is not so soft that it can be easily bent by its own weight. Therefore, the optical waveguide 4 is stably fitted in the groove 23a and bent toward the medium side substrate 24. There is no. Therefore, the optical waveguide 4 is in a state of being inserted into the head main body 20 via the groove 23a.

  The proximal end side of the optical waveguide 4 is connected to the optical signal controller 5 through the beam 3 and the carriage 11. The light beam L guided from the optical waveguide 4 arranged in this way into the head main body 20 strikes the mirror surface 23 d of the arm side substrate 23 and is reflected, and then enters the microlens 26 of the medium side substrate 24. Then, the light is condensed by the micro lens 26, proceeds toward the facing surface 24 a inside the medium side substrate 24, and enters the tip 27. The spot size is narrowed down by the tip 27 so that the spot light S is emitted to the outside.

  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 above will be described below.

  First, the spindle motor 7 is driven to rotate the disk D in a certain direction. Next, the actuator 6 is operated to scan the beam 3 in the XY directions via the carriage 11. As a result, the recording head 2 can be positioned at a desired position on the disk D as shown in FIG. At this time, the recording head 2 receives a force that rises by the two ridges 24b formed on the facing surface 24a of the head body 20, and is pressed against the disk D side with a predetermined force by the beam 3 or the like. The recording head 2 floats at a position separated from the disk D by a predetermined distance H (for example, several nm to several tens of nm) as shown in FIG.

  Even if the recording head 2 receives the wind pressure generated due to the undulation (surface fluctuation) of the disk D, the displacement in the Z direction is absorbed by the beam 3 and the X and Y axes are absorbed by the gimbal portion 25. Since it can be displaced around the Z axis, it is possible to absorb the wind pressure caused by the swell. Therefore, the recording head 2 can be floated in a stable state. This levitation will be described later in detail.

  Here, when recording information, the controller 8 operates the optical signal controller 5. Then, the optical signal controller 5 receives the instruction from the control unit 8 and causes the light beam L to enter from the proximal end side of the optical waveguide 4. The incident light beam L travels in the core of the optical waveguide 4 toward the tip side, and as shown in FIG. 4, the mirror surface 23d of the arm-side substrate 23 constituting the spot light generating means 21 formed in the head main body 20. To be introduced. Then, the introduced light beam L is reflected by the mirror surface 23 d and changes its direction, and then enters the microlens 26 of the medium side substrate 24. The light beam L incident on the microlens 26 travels toward the tip 27 formed on the facing surface 24a side in the medium side substrate 24 while being condensed by the microlens 26. The light beam L that has reached the tip 27 propagates toward the end surface 27b while being repeatedly reflected by the four side surfaces 27a. At this time, the spot size of the light beam L gradually decreases toward the end face 27b. Then, it is emitted toward the disk D from the end face 27b side as the spot light S having a reduced spot size.

  As described above, the light beam L introduced from the optical waveguide 4 by the spot light generating means 21 can be condensed to generate the spot light S on the facing surface 24a side. In addition, since the light shielding film 28 is formed on the four side surfaces 27a of the tip 27, the light beam L can be efficiently converted to the spot light S without being lost.

  On the other hand, the disk D is locally heated by the spot light S to temporarily reduce the coercive force or change the crystal structure. As a result, various information can be recorded and reproduced on the disk D by using the spot light S. In the case of reproducing the recording, the reproduction can be performed by detecting the difference in the reflectance of the light from the disk D.

  By the way, the tip of the optical waveguide 4 for introducing the light beam L is inserted into the head main body 20 via the groove 23a that functions as a light guide holder. Moreover, the optical waveguide 4 is slidably held unlike a conventional adhesively fixed one. Therefore, the head main body 20 floating on the disk D can move freely without being blocked by the optical waveguide 4. That is, in the conventional apparatus, the movement of the head has been hindered by the tension of the optical fiber or the like, but since the optical waveguide 4 is slidably held as described above, the movement of the head main body 20 is prevented. There is no fear of obstruction. Therefore, even if the rotating disk D causes surface vibration, the posture of the head main body 20 can be smoothly changed by the surface vibration. Therefore, the head body 20 can be stably levitated.

  This stable levitation will be described in more detail.

  In this embodiment, the optical waveguide 4 arranged substantially parallel to the disk surface D1 is slidably held along the longitudinal direction of the optical waveguide 4. Here, when the head main body 20 rotates around the Z axis perpendicular to the disk surface D1 as shown in FIGS. 12 and 13 due to the influence of the surface deflection of the disk D (yaw angular motion). Since the optical waveguide 4 tries to follow the posture change of the head main body 20, the optical waveguide 4 starts to bend to the left or right (vertical direction on the paper surface). However, the optical waveguide 4 is flexible and slidable in the longitudinal direction. Therefore, the optical waveguide 4 can be shifted in the longitudinal direction (right direction in the drawing) while bending. Therefore, the posture of the head body 20 can be changed without hindering movement of the optical waveguide 4.

  Further, the head main body 20 rotates around the X axis (the direction horizontal to the disk surface D1 and perpendicular to the Y axis along the axis of the optical waveguide 4) as shown in FIGS. In this case (pitch angle motion), the optical waveguide 4 can be shifted in the longitudinal direction (right direction on the paper surface) while bending in either the upper or lower direction (up and down direction on the paper surface). Therefore, the posture of the head main body 20 is changed without the movement of the optical waveguide 4 being hindered.

  When the head main body 20 rotates around the Y axis along the axis of the optical waveguide 4 due to the influence of surface deflection (roll angular motion), as shown in FIGS. In contrast, only the head body 20 rotates without the optical waveguide 4 being bent or displaced. Therefore, the posture of the head main body 20 can be changed without the movement of the optical waveguide 4 being hindered.

  As described above, the head main body 20 can smoothly change its posture without being obstructed by the movement of the optical waveguide 4 in any case, and thus can stably float.

  Particularly, since the recess 23c is filled with the lubricating oil W and the optical waveguide 4 is disposed therein, the frictional force is reduced when the optical waveguide 4 slides relative to the head body 20. Therefore, the optical waveguide 4 can be slid more smoothly. Accordingly, the posture of the head main body 20 can be changed more smoothly, the followability can be improved, and more stable flying can be realized.

  Furthermore, in the present embodiment, a range of a certain distance from the tip of the optical waveguide 4 is suspended in the air and is held in a non-contact state with respect to the groove portion 23a and the taper portion 23b. Therefore, the tip of the optical waveguide 4 does not come into contact with the groove 23a or the taper 23b at the beginning of sliding or during sliding. Since this tip portion is a portion which becomes an outer edge in physical design, the contact area is larger than other portions. Therefore, when this tip part contacts the groove part 23a or the taper part 23b, the entire frictional resistance becomes large and it becomes difficult to slide.

  However, since the range of a certain distance from the tip of the optical waveguide 4 is non-contact as described above, the optical waveguide 4 can be smoothly slid without being caught. Also in this respect, the head body 20 can be stably floated.

  The recess 23c has an opening only on the surface of the head main body 20 where the optical waveguide 4 is inserted, and has a bag shape containing the lubricating oil W. As a result, even when the information recording / reproducing apparatus 1 receives an impact due to a fall or the like, the lubricating oil W does not leak and is stably held in the recess 23c. This makes it possible to record and reproduce information stably over a long period of time.

  Moreover, the optical waveguide 4 is shifted in the longitudinal direction, which is the same direction as the direction in which the light beam L is introduced into the mirror surface 23d. Therefore, no matter how the posture of the head main body 20 changes, the light flux L can always be introduced at the same position with respect to the mirror surface 23d constituting the spot light generating means 21. That is, the introduction point may be shifted only by changing the distance between the mirror surface 23d and the optical waveguide 4 (that is, changing the distance at which the light beam L emitted from the optical waveguide 4 reaches the mirror surface 23d). Absent.

  Therefore, the spot light S can be generated at the same position even if the posture of the head body 20 changes. However, since the distance between the optical waveguide 4 and the mirror surface 23d changes, the spot size changes due to the diffusion of light, and the generated spot light S becomes blurred (the spot size increases). However, since the position of the spot light S itself does not change as described above, the peak position of the spot light S can be made the same position, and the reduction in light efficiency can be minimized. Therefore, the light beam L can be condensed without waste to form the spot light S, and stable recording and reproduction can be performed.

  Further, since the recording head 2 of the present embodiment introduces the light beam L directly into the head body 20 using the optical waveguide 4 without propagating in the air, even if the attitude of the head body 20 changes, the recording head 2 is stable. It is possible to guide the light beam L. In addition, since the head main body 20 is stably floated on the disk D as described above, it is easy to control the distance between the facing surface 24a and the disk surface D1 to a predetermined distance H. Therefore, the generated spot light S can be reliably acted on the disk D.

  In addition, by using a lens in which the light exit surface of the light guide 4 is processed into a lens shape, the light emitted from the light guide 4 can be easily converted into parallel light. In this case, even if the optical waveguide 4 is displaced in the longitudinal direction, the spot size irradiated to the mirror surface 23d is not affected, and as a result, the size and efficiency of the spot light S are not affected. As a result, stable levitation was achieved while maintaining stable light guide.

  Further, when the light beam L is introduced into the head body 20, the recording head 2 uses the optical waveguide 4 to directly transmit the light beam L to the head, unlike the conventional one in which optical components and light sources are arranged around the head. It is introduced into the mirror surface 23d of the main body 2. Therefore, the number of parts can be minimized, and downsizing can be achieved with a compact design.

  As described above, according to the recording head 2 of the present embodiment, it is possible to achieve both stable levitation and stable light guide, both of which are conventionally difficult. As a result, it is possible to stably float on the disk D due to a smooth posture change, and to guide the light beam L without being influenced by the posture change, and to perform reliable recording and reproduction.

  Further, since the optical waveguide 4 that is inexpensive and generally used is used, the cost can be reduced and the design can be simplified. In addition, since the light guide holder can be configured only by forming the groove 23a without adding new parts to the head body 20, it is possible to reduce the size and to simplify the design also in this respect. be able to. In particular, since the optical waveguide 4 is guided by the groove 23a, a stable sliding operation can be performed.

  Further, according to the information recording / reproducing apparatus 1 of the present embodiment, since the recording head 2 is provided, stable recording / reproducing can be performed without being affected by the surface shake of the disk D, and the quality can be improved. Can be planned. Further, since the recording head 2 is downsized with a compact design, the information recording / reproducing apparatus 1 itself can be downsized.

  In addition, in the said 1st Embodiment, although the groove part 23a was formed in the cross-section V shape, it is not limited to this shape, For example, you may form in a U shape according to the curved surface of the optical waveguide 4. FIG. Absent. Further, instead of the optical waveguide 4, an optical fiber may be used.

Moreover, in the said 1st Embodiment, although the taper part 23b was formed in the side from which the light beam L was radiate | emitted (the front end side of the optical waveguide 4), as shown in FIG. It may also be formed on the base end side of the waveguide 4. That is, the tapered portion 23b may be formed so as to be adjacent to both sides of the groove portion 23a. By carrying out like this, since sliding with the low friction of the optical waveguide 4 and leakage prevention of the lubricating oil W can be made compatible, it is more preferable. The tapered portion 23b on the side on which the light beam L is incident is an inclined surface formed so that the distance from the optical waveguide 4 is gradually separated toward the proximal end of the optical waveguide 4, and dicing or the like is performed. It can be easily produced simply by cutting.
(Embodiment 2)
Next, a second embodiment according to the present invention will be described with reference to FIG. In the second embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  The difference between the second embodiment and the first embodiment is that, in the first embodiment, the optical waveguide 4 is slidably held by the groove 23a formed in the arm side substrate 23, but in the second embodiment, That is, the optical waveguide 4 is slidably held using the recess 42 and the head main body 41 is formed by cutting out one substrate.

  That is, the recording head 40 of this embodiment includes a head main body 41 in which a recess 42 is formed as shown in FIG. The recess 42 is formed along the longitudinal direction of the optical waveguide 4 so as to be exposed on one side surface of the head body 41.

The recess 42 is formed in a size slightly larger than the diameter of the optical waveguide 4. The optical waveguide 4 is slidably held while penetrating through the recess 42. Therefore, in this embodiment, this recessed part 42 functions as a light guide holder. The recess 42 is filled with lubricating oil W, and the lubricating oil W is interposed between the inner wall of the recess 42 and the optical waveguide 4. Since the concave portion 42 is opened to the outside only on one side surface of the head main body 41, the lubricating oil W filled therein does not leak even when subjected to an impact from the outside. Further, since the head main body 41 is made of a single substrate, it can be made thin, so that a compact information recording / reproducing apparatus can be realized and can be manufactured at low cost. Other functions and effects are the same as those of the first embodiment.
(Embodiment 3)
The light guide holder holds the optical waveguide 4 so as to be slidable. In the first embodiment, the light guide holder includes a groove 23a, a taper 23b, a recess 23c, a mirror surface 23d, and a surface facing them. Of course, the present invention is not limited to this. Specifically, the light guide holder may include a cylindrical space formed by two substrates (arm-side substrate 23 and medium-side substrate), or a cylindrical space formed on a single substrate. Or a container having a cylindrical space other than the substrate.

  A third embodiment according to the present invention will be described with reference to FIG. In the third embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  The difference between the third embodiment and the first embodiment is that, in the first embodiment, the optical waveguide 4 is slidably held by the groove portion 23a formed in the arm side substrate 23, but in the third embodiment, A point where the optical waveguide 4 is slidably held using the recess 52, a point where the head main body 51 is formed by cutting out one substrate, and a light guide holder 53 having the recess 52. Is different from the head main body 51 and is bonded and fixed to the head main body 51.

  In the recording head 50 having such a structure, each component can be easily manufactured at low cost, and can be assembled while performing optical alignment. Therefore, a head finely adjusted to maximize the light efficiency is manufactured. be able to.

It is a figure which shows 1st Embodiment which concerns on this invention, Comprising: It is a block diagram of an information recording / reproducing apparatus. FIG. 2 is an enlarged side view of a recording head constituting the information recording / reproducing apparatus shown in FIG. 1. FIG. 3 is a diagram of the recording head shown in FIG. 2 viewed from the disk side. FIG. 3 is a cross-sectional view of the recording head shown in FIG. FIG. 5 is a cross-sectional arrow view AA of the recording head illustrated in FIG. 4. FIG. 3 is a perspective view of an arm-side substrate that constitutes the head main body of the recording head shown in FIG. 2 and shows a state in which an optical waveguide is inserted into a groove. It is sectional drawing which cut | disconnected the arm side board | substrate shown in FIG. 6 along the axis line of an optical waveguide. It is sectional drawing which looked at the arm side board | substrate shown in FIG. 7 from the arrow B direction. It is an enlarged view in the dotted-line frame shown in FIG. FIG. 3 is a perspective view of a medium side substrate constituting a head main body of the recording head shown in FIG. 2. FIG. 3 is a diagram for explaining the relationship between the posture of the head main body and the optical waveguide shown in FIG. 2, and is a view of the arm-side substrate viewed from the medium-side substrate when the head main body is in a normal posture. . FIG. 12 is a diagram illustrating a state in which the head main body is rotated about an axis perpendicular to the disk surface due to the surface deflection of the disk from the state illustrated in FIG. FIG. 13 is a diagram illustrating a state in which the head main body is rotated in a direction opposite to that in FIG. 12. FIG. 3 is a diagram for explaining the relationship between the posture of the head main body and the optical waveguide shown in FIG. 2, and is a cross-sectional view showing a state in which the head main body is rotated around an axis horizontal to the disk surface due to surface deflection of the disk. It is a figure which shows the state which the head main body rotated in the direction opposite to FIG. FIG. 3 is a diagram for explaining the relationship between the posture of the head main body and the optical waveguide shown in FIG. 2, and is a cross-sectional view showing a state in which the head main body is rotated around the axis of the optical waveguide due to surface deflection of the disk. FIG. 17 is a diagram illustrating a state in which the head main body is rotated in a direction opposite to that in FIG. 16. It is a figure which shows the modification of 1st Embodiment, Comprising: It is a perspective view of the arm side board | substrate with which the taper part was formed in the both sides of a groove part. FIG. 6 is a cross-sectional view of a recording head according to a second embodiment. FIG. 6 is a cross-sectional view of a recording head according to a third embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Information recording / reproducing apparatus 2 Recording head 3 Beam 4 Optical waveguide (light guide part)
5 Optical signal controller (light source)
6 Actuator 7 Spindle motor (rotary drive)
DESCRIPTION OF SYMBOLS 8 Control part 9 Housing 9a Concave part 10 Bearing 11 Carriage 12 Suspension 20 Head main body 21 Light generation means 23 Arm side board | substrate 23a Groove part (light guide part holder)
23b Tapered portion 23c Recessed portion 23d Mirror surface 24 Medium side substrate 24a Opposing surface 24b Convex strip portion 25 Gimbal portion 26 Microlens 27 Tip 27a Tip side surface 27b Tip end surface 28 Light shielding film 40 Recording head 41 Head main body 42 Concave 50 Recording head 51 Head body 52 Recess 53 Light guide holder D Disk (recording medium)
D1 Disk surface H Distance between disk surface and head L Light flux M
S Spot light W Lubricant

Claims (8)

A recording head that records and reproduces information on a recording medium that rotates in a certain direction using spot light generated by condensing the introduced light beam,
A head body having spot light generating means disposed in a state of being floated by a predetermined distance from the surface of the recording medium and generating the spot light on a side facing the recording medium;
A light guide that is inserted into the head main body via a light guide holder and introduces the luminous flux into the spot light generating means;
A fluid interposed between the light guide section and the inner wall of the light guide section holder,
The light guide holder is formed in a bag shape by narrowing an opening that opens only on a surface of the head body into which the light guide is inserted,
The recording head, wherein the fluid fills the inside of the light guide holder.   2. The recording head according to claim 1, wherein the inner wall of the light guide holder is formed by a medium side substrate disposed on the recording medium side and an arm side substrate facing the medium side substrate. Recording head. The recording head according to any one of claims 1 and 2,
The light guide unit is a flexible light guide unit arranged to extend in a direction substantially parallel to the surface of the recording medium, and the light guide unit holder is slid along the longitudinal direction. A recording head characterized by being held in the head. The recording head according to any one of claims 1 and 2,
The recording head, wherein the light guide unit is an optical fiber or an optical waveguide. The recording head according to any one of claims 1 and 2,
The recording head according to claim 1, wherein the light guide holder is a groove that contacts at least a part of the light guide. The recording head according to any one of claims 1 and 2,
The light guide unit is slidably held by the light guide unit holder in a state where a certain distance from the tip is not in contact with the light guide unit holder. . The recording head according to any one of claims 1 and 2,
The light guide holder includes a condensing part that condenses the light beam emitted from the light guide part,
The recording head according to claim 1, wherein the fluid is provided in an optical path until a light beam emitted from the light guide unit reaches the light collecting unit. A recording head according to any one of claims 1 to 7,
The recording can be performed in a direction parallel to the surface of the recording medium, and can rotate about two axes parallel to the surface of the recording medium and perpendicular to each other and about a vertical axis perpendicular to the surface of the recording medium. A beam that supports the head on the tip side,
A light source for making the light beam incident on the light guide unit;
An actuator for supporting the base end side of the beam and moving the beam in a direction parallel to the surface of the recording medium;
A rotation drive unit for rotating the recording medium in the fixed direction;
And a control unit that controls the operation of the light source according to the information to be recorded.

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