JP4356655B2 - Solid immersion lens, optical pickup device, and optical recording / reproducing device - Google Patents

Description

  The present invention relates to a solid immersion lens, an optical pickup device using the same, and an optical (or magneto-optical) recording / reproducing device, and more specifically, using a material having a high refractive index of the optical lens. The present invention relates to a solid immersion lens, an optical pickup device, and an optical recording / reproducing apparatus that can be applied to a so-called near-field optical recording / reproducing system that performs recording / reproducing on an optical (or magneto-optical) recording medium by increasing the numerical aperture of the condenser lens. .

Recording media (including magneto-optical recording media) represented by compact disc (CD), mini disc (MD), and digital versatile disc (DVD) are widely used as storage media for music information, video information, data, programs, and the like. It's being used. However, in order to further improve the sound quality, image quality, longer time, and capacity of music information, video information, data, programs, etc., a larger capacity recording medium and an optical recording / reproducing apparatus for recording / reproducing the recording medium (Including a magneto-optical recording / reproducing apparatus) is desired.
Therefore, in order to cope with these, in the optical recording / reproducing apparatus, the wavelength of the light source, for example, the semiconductor laser is shortened, the numerical aperture of the condensing lens is increased, and the light spot converged through the condensing lens is reduced. The diameter has been reduced.

  For example, with regard to semiconductor lasers, GaN semiconductor lasers whose oscillation wavelength has been shortened from the 635 nm to 400 nm bands of conventional red lasers have been put into practical use, and thereby the diameter of the light spot is being reduced. Further, for example, for further shortening of the wavelength, a far ultraviolet solid-state laser UW-1010 manufactured by Sony Corporation that continuously oscillates light having a single wavelength of 266 nm has been put on the market. It is being planned. In addition to this, research and development of a Nd: YAG laser double wave laser (266 nm band), a diamond laser (235 nm band), a GaN laser double wave laser (202 nm band), and the like are underway.

  Further, by using an optical lens having a large numerical aperture represented by a solid immersion lens, for example, a condensing lens having a numerical aperture of 1 or more is realized, and an object surface of the solid immersion lens used for the condensing lens is used as a light source. A so-called near-field optical recording / reproducing system in which recording / reproducing is performed by bringing the recording medium close to about one-tenth of the wavelength has been studied (see, for example, Patent Document 1).

  In this near-field optical recording / reproducing system, it is important to maintain the distance between the recording medium and the solid immersion lens in an optical contact state with high accuracy. In addition, the diameter of the light beam emitted from the light source and incident on the solid immersion lens becomes small, and the distance between the recording medium and the solid immersion lens is very small, about tens of nanometers or less, so the recording medium and the solid immersion lens The so-called tilt margin becomes very small, and the shape of the solid immersion lens is greatly restricted.

  Conventionally, as a solid immersion lens (SIL) considering a tilt margin, those shown in FIGS. 14A and 14B are known. The solid immersion lens shown in FIG. 14A has a structure in which a convex condensing part is provided at the center of the objective surface of the super hemispherical lens, so that the distance between the objective surface excluding the convex part and the recording medium. To increase the tilt margin (Non-patent Document 1). In addition, the solid immersion lens shown in FIG. 14B has a structure in which a conical inclined portion is provided on the objective surface side of the hemispherical lens, so that the distance between the objective surface and the recording medium is increased. The margin is improved (see, for example, Patent Document 2).

When the solid immersion lens having such a configuration is applied to, for example, an optical recording / reproducing apparatus, the solid immersion lens is attached to an optical pickup apparatus having a biaxial actuator, and the distance between the recording medium and the solid immersion lens is optically determined. Keep in contact. When used for magneto-optical recording, a magnetic head device used for magnetic recording / reproducing is incorporated in the optical pickup device, and similarly the distance between the recording medium and the solid immersion lens is maintained in an optical contact state. It is supposed to be configured.
Japanese Laid-Open Patent Publication No. 5-189796 JP 2003-161801 A ISOM'04 Technical Digest pp210-211

  However, since the solid immersion lens of FIG. 14A described above has a convex portion on the objective surface, the convex shape located between the objective surface and the recording medium when the recording medium rotates. An air flow is generated around the part. Then, the dust floating on the recording medium collides with the convex part of the solid immersion lens by this air flow, and the dust adheres to the vicinity of the condensing part provided near the tip of the convex part. As a result, there arises a problem that it is difficult to stably record and reproduce by blocking light incident on the lens.

  Similarly, since the solid immersion lens of FIG. 14B described above has a conical inclined portion on the object surface side, when the recording medium rotates, air flows near the tip of the inclined portion. appear. Then, due to this air flow, dust floating on the recording medium collides with the tip portion of the inclined portion, and the dust adheres to the vicinity of the light collecting portion provided at the tip portion of the inclined portion, and as a result, the lens This causes a problem that it becomes difficult to stably record and reproduce light that is blocked by the incident light.

  In consideration of the above-described problems, the present invention improves the dust resistance of a solid immersion lens, and can perform stable optical recording and reproduction without dust adhering to the light condensing portion of the lens. An optical pickup device and an optical recording / reproducing device are provided.

  The present invention is a solid immersion lens having an upper lens structure and a lower lens structure, and the lower lens structure has a convex portion having a condensing portion, and a skirt portion is provided on the convex portion. The configuration.

Preferably, the skirt portion has an inclined portion that is inclined toward the light collecting portion.
More preferably, it is appropriate that the upper lens structure has an inclined portion inclined toward the light collecting portion.

  The present invention is an optical pickup device comprising at least a light source and a condenser lens composed of a solid immersion lens and an optical lens, wherein the solid immersion lens has an upper lens structure and a lower lens structure, The lower lens structure has a convex portion having a condensing portion, and a skirt portion is provided on the convex portion.

  The present invention also includes at least a light source, a condensing lens composed of a solid immersion lens and an optical lens, an optical pickup device that condenses light on an optical recording medium and performs recording and / or reproduction, and An optical recording / reproducing device comprising a condensing lens and a drive control means for driving and controlling the optical pickup device, wherein the solid immersion lens has an upper lens structure and a lower lens structure, and the lower lens structure is a condensing lens It has the convex part which has a part, and it is set as the structure provided with the skirt part in this convex part.

  In the solid immersion lens according to the present invention, the convex portion having the condensing portion is provided with the skirt portion, and the upward air flow is generated, so that dust adhering to the condensing portion can be reduced. In addition, the optical pickup device and the optical recording / reproducing device using the solid immersion lens can perform stable recording / reproducing with near-field light.

  According to the solid immersion lens of the present invention, it is possible to reduce dust adhering to the condensing part of the lens.

  Further, according to the optical pickup device and the optical reproducing / recording device using the solid immersion lens of the present invention, it is possible to reduce the dust adhering to the condensing part of the solid immersion lens, so that the recording / reproducing by the stable near-field light is possible. Can do.

  Examples of the best mode for carrying out the present invention will be described below, but the present invention is not limited to the following examples.

  FIG. 1 is a schematic configuration diagram of an example of an optical recording / reproducing apparatus including an optical pickup device according to the present invention.

  As shown in FIG. 1, in this example, an example of a light irradiation mode in the case of recording on a disk-shaped recording medium 9 based on information from the information source 1 is shown, and a light source comprising a laser diode (LD) or the like. The light emitted from 3 is modulated by the information source 1 in response to the information signal, and the output is controlled by the automatic power control means (APC) 2. The emitted light is converted into parallel light by the collimator lens 4 in the optical unit 41 and is incident on the head unit 42 via the beam spiriter 6 and the mirror 7. The head unit 42 includes an optical system that irradiates the recording medium 9 with near-field light by a condensing lens that achieves a numerical aperture of 1 or more, which includes the solid immersion lens 10 and the optical lens 16 including an aspheric lens. Is done. The head unit 42 is configured by installing, for example, the solid immersion lens 10 and the optical lens 16 on the actuator 8 constituting the driving unit 43. The light emitted from the optical unit 41 is irradiated as near-field light onto the recording surface on which information of the recording medium 9 is recorded by the head unit 42. The optical pickup device 47 is configured by a portion surrounded by a dotted line shown in the figure.

  The recording medium 9 is held by a moving mechanism unit 46 including, for example, a rotating unit 15 that rotates and moves the recording medium 9, and although not shown, for example, a horizontal moving mechanism that translates the head unit 42 side along the recording surface of the recording medium 9. By the interlocking, the near-field light emitted from the head unit 42 is scanned along, for example, a spiral or concentric recording track along the surface of the recording medium 9.

  The detection mode of the spots arranged in this way will be described with reference to FIG. 1 again. In this case, the light reflected from the recording medium 9 is reflected by the beam splitter 6 through the head unit 42 and detected by the light detection unit 44 including the photodetector (PD) 12. Then, the return light amount detected in this way is input to the gap servo 13, converted from a detected light amount value into a control signal based on a detection method described later, a gap control signal is output, and a drive unit by the actuator 8 43 is input to correct the gap. As a result, the gap between the solid immersion lens 10 and the recording medium 9 is kept constant.

  FIG. 2 is a schematic configuration diagram illustrating an incident mode in which incident light is incident on the recording medium 9 via the head unit 42. The aspherical lens 16 and the solid immersion lens 10 are arranged in this order from the light source side, and the head portion 42 that irradiates the recording medium 9 with near-field light is installed in an actuator 8 such as a biaxial actuator. In the illustrated example, incident light A is incident on the solid immersion lens 10 at an angle at which the incident light is totally reflected. In FIG. 2, an alternate long and short dash line c indicates the optical axis of the incident light. The light that has soaked into the recording medium 9 from the light condensing part 20 on the recording medium side end face of the solid immersion lens 10 forms a spot on the recording medium 9.

  Next, with reference to FIGS. 3A and 3B, a method for detecting a gap between the solid immersion lens 10 and the recording medium 9 for the recording medium 9 using near-field light will be described. 3A is a schematic configuration diagram showing a gap between the recording medium 9 and the head portion 42, that is, a gap between the recording medium side end surface of the solid immersion lens 10, and FIG. 3B is a total reflection with respect to the gap. It is a figure which shows the change of return light quantity. In FIG. 3A, parts corresponding to those in FIG.

  When the distance (gap) between the solid immersion lens 10 and the recording medium 9 is generally equal to or greater than the distance at which near-field light that is ¼ or less of the wavelength of incident light is generated, that is, a broken-line arrow in FIG. In the far field region indicated by Ff, the light incident at an angle causing total reflection at the end face of the solid immersion lens 10 is totally reflected at this end face, and as shown in FIG. Is always constant.

  On the other hand, the gap between the solid immersion lens 10 and the recording medium 9 is approximately ¼ or less (generally, 70 nm or less) of the wavelength λ of incident light, and is equal to or less than the distance at which near-field light is generated. When entering the field region, a part of the light incident at the angle of total reflection from the condensing unit 20 of the solid immersion lens 10 begins to permeate, and the return light amount Lr decreases. When the solid immersion lens 10 and the recording medium 9 come into contact with each other (that is, at the position where the gap is 0), all of the incident light is transmitted to the recording medium 9, so that the return light amount Lr becomes zero.

Such a change in the amount of return light in the gap region that generates near-field light occurs in the near-field region indicated by the dashed arrow Fn, and the amount of return light gradually decreases as the gap approaches the recording medium from the position of approximately λ / 4. First, a curve is obtained that decreases substantially linearly in the middle portion and gradually gradually decreases again in an area closer to the recording medium surface.
Therefore, the gap between the solid immersion lens 10 and the recording medium 9 is detected from the return light amount by utilizing the fact that the total reflected return light amount changes substantially linearly within a certain range with respect to the gap length. In the case where the gap is held at a constant value d as shown in FIG. 3B, for example, the actuator 8 or the like is controlled by the gap control unit so that the return light amount Lr is held at the target value α corresponding to the gap. By driving, the gap between the solid immersion lens 10 and the recording medium 9 can be controlled to be constant, for example, 20 nm.

  Next, an example in which the present invention is applied to a playback system of a recording / playback apparatus will be described. FIG. 4 shows a schematic configuration diagram of a reproducing apparatus when spots are formed on a recording medium 9 using a light source 3 such as one laser. 4, parts corresponding to those in FIG. 1 are denoted by the same reference numerals, and redundant description is omitted.

  In this case, the reproduction RF signal can be detected by receiving the return light amount by the photodetector 12. Further, the servo signal can be detected by observing the reproduction RF signal through a low-pass filter, and an error signal to the gap servo 13 can be obtained. As a result, stable gap control can be performed and good reproduction can be performed.

  FIG. 5A is a cross-sectional view of an embodiment of a solid immersion lens according to the present invention. FIG. 5B is a plan view seen from the light collecting unit side for facilitating understanding of the shape of the solid immersion lens according to the present invention.

  The solid immersion lens 10 in this example includes an upper lens structure 31 and a lower lens structure 32 composed of convex portions. The upper lens structure 31 is formed by a super hemispherical spherical portion 31a and a conical portion 31b connected thereto. In addition, the conical portion 31 b provided in the upper lens structure 31 is formed with an inclined surface 11 that is inclined toward the light collecting portion provided in the lower lens structure 32.

  The lower lens structure is formed by a convex portion 32 provided so as to be connected to the tip of the conical portion 31b. The convex portion 32 has an inverted conical shape as a skirt portion, and an objective surface 20 that also serves as a condensing portion is formed on the tip side of the convex portion 32. The objective surface 20 has a flat surface facing the recording medium 9. Further, the inverted conical inclined surface 33 which is a skirt portion provided on the convex portion 32 is formed so as to expand toward the objective surface 20.

  Further, in the solid immersion lens 10 of this example, the inclination angle θ1 of the inclined surface 11 of the conical portion 31b provided in the upper lens structure 31 is the same as that of the inverted conical inclined surface 33 provided in the lower lens structure 32. It is formed so as to be larger than the inclination angle θ2 it has. Specifically, the inclination angle θ1 is 70 degrees and the inclination angle θ2 is 45 degrees. Thus, the lower lens structure 32 can be easily manufactured by setting the inclination angle θ2 to 45 degrees. Note that the inclination angle θ is such that a line parallel to the optical axis c passing through the center of the condensing portion and a cross-sectional line of each inclined surface intersect at a position where the upper lens structure 31 and the lower lens structure 32 are connected. An angle defined.

FIG. 6 is a sectional view of another embodiment of the solid immersion lens according to the present invention. In FIG. 6, parts corresponding to those in FIG.
The upper lens structure 31 of the solid immersion lens 10 in this example is formed of a hemispherical spherical portion 31a and a conical portion 31b connected to the hemispherical spherical portion 31a. Other structures are the same as those of the solid immersion lens 10 shown in FIG.

FIGS. 7A, 7B, and 7C are cross-sectional views showing another embodiment of the lower lens structure of the solid immersion lens of the present invention.
In the lower lens structure of the solid immersion lens 10 shown in FIG. 7A, a cylindrical portion 32b is formed so as to be connected to the tip of an inverted conical portion 32a as a skirt portion provided in the convex portion 32. Is. Further, the light condensing part 20 is formed at the tip of the cylindrical part 32b.

  In the lower lens structure 32 of the solid immersion lens 10 shown in FIG. 7B, an inverted conical portion 32d as a skirt portion is formed so as to be connected to the tip of the cylindrical portion 32c provided on the convex portion 32. It is what. The condensing part 20 is formed in the front-end | tip part of this reverse cone-shaped part 32d.

  The lower lens structure 32 of the solid immersion lens 10 shown in FIG. 7C is connected to the tip of the cylindrical portion 32e provided on the convex portion 32 and has a larger cross-sectional area as the skirt portion than the cylindrical portion 32e. A cylindrical portion 32f having the shape is formed. And the condensing part 20 is formed in the front-end | tip part of this cylindrical part 32f.

8A and 8B are cross-sectional views of still another embodiment of the solid immersion lens according to the present invention.
The solid immersion lens 10a shown in FIG. 8A includes an upper lens structure 31 and a lower lens structure 32 having a convex portion. The upper lens structure 31 does not have a conical shape portion, and has a hemispherical shape portion. Only formed. The upper lens structure 31 is not limited to the hemispherical shape of this example, and may be formed in a super hemispherical shape.

  The solid immersion lens 10b shown in FIG. 8B includes an upper lens structure 31 and a lower lens structure 32 having a convex portion. The upper lens structure 31 has a cylindrical portion without having a conical portion. Formed only by. The upper lens structure 31 may form an upper lens structure by adding a Fresnel lens structure, for example.

  FIG. 9A shows the air generated by the rotation of the recording medium when dust D enters the solid immersion lens when a so-called tip cone type solid immersion lens having a hemispherical portion and a conical portion connected thereto is used. It is a schematic diagram which shows the path | route at the time of winding up by a flow. FIG. 9B is a plan view used for explaining the entering direction of the dust D when entering the solid immersion lens.

  First, dust D emitted from the position of X = −100 μm on the X axis starts to enter toward the center point x of the solid immersion lens 10. Next, when the dust D approaches the center point x of the solid immersion lens 10 to a position along the X axis, the rotation of the recording medium 9 causes the space between the recording medium 9 and the inclined surface 11 of the solid immersion lens 10. The recording medium 9 is wound up under the influence of the airflow generated in the space. At this time, the length of the perpendicular line segment between the recording medium 9 and the inclined surface 11 of the solid immersion lens 10 at the position where the dust D is closest to the center point x of the solid immersion lens 10 on the X axis is L1. It is defined as As will be described later, the tip cone type solid immersion lens used for comparison with the solid immersion lens 10 of the present example has an inclination angle θ generated by the intersection of the optical axis c and the cross-sectional line of the inclined surface 11 of 60 degrees. Set.

Next, the principle of dust D being rolled up on the recording medium will be described in detail with reference to FIG.
FIG. 10 is a schematic sectional view showing the positional relationship between the solid immersion lens and the recording medium.
At this time, let S be a space formed between the inclined surface 11 of the solid immersion lens 10 and the recording medium 9. In the air existing in the space S, when the recording medium (disk) 9 rotates, an air flow that flows upward as indicated by the arrow f is generated, and the dust D that has entered the predetermined position flows into the recording medium 9. Will be rolled up.

  FIG. 11 shows the result of the dust D penetration experiment using the solid immersion lens 10 of this example shown in FIG. 5 and the tip cone type solid immersion lens with the inclination angle θ set to 60 degrees. Indicates.

  FIG. 11 is a graph showing the result of measuring L1 by shifting the entry position (dust initial position) of dust D entering the center x of the solid immersion lens. The vertical axis of the figure represents the previously defined L1, and the horizontal axis of the figure represents the dust entry position as a deviation from the center x of the solid immersion lens on the Y axis shown in FIG. 9B. Here, the linear velocity of the recording medium (disk) is set to 6.3 m / s, the emission position of the dust D is set to a height of 10 nm from the surface of the recording medium 9, and the diameter of the dust D is set to 20 nm.

FIG. 12 shows the results when the same experiment was performed with the dust D emission position set to 50 nm from the surface of the recording medium 9 and the diameter of the dust D set to 100 nm.
FIG. 13 shows the results of the same experiment when the dust D emission position is 100 nm from the surface of the recording medium 9 and the dust D diameter is 200 nm.

  Regardless of the conditions of the experiment, as shown in the graphs of FIGS. 11, 12, and 13, the solid immersion lens 10 of the present example has L1 as compared with the conventional solid immersion lens. Can be increased. That is, dust entering the central portion x of the solid immersion lens 10 is wound up at a position further away from the central portion x, so that the dust is sandwiched between the solid immersion lens 10 and the recording medium 9. And the possibility of adhering to the condensing part 20 of the lens is reduced. Therefore, in the solid immersion lens 10 of this example, the dust D entering the light condensing unit 20 of the solid immersion lens 10 can be efficiently removed as compared with the conventional tip-conical solid immersion lens. It is possible to prevent dust from adhering to 20.

  The reason is that according to the solid immersion lens 10 of this example, the upward flow generated in the air existing in the space S is caused by the skirt portion provided in the convex portion 32, so that the conventional tip cone type solid immersion lens is used. Since it is stronger than the case where a lens is used, it is considered that dust that enters at a position further away from the lens center part x is wound up.

  In addition, according to the optical pickup device using the solid immersion lens 10 of the present example, the possibility of dust D being sandwiched between the solid immersion lens 10 and the recording medium 9 is reduced, so that the near-field light is stable. An optical pickup operation can be performed. Further, according to the optical recording / reproducing apparatus using the solid immersion lens 10 of this example, the possibility of dust D being sandwiched between the solid immersion lens 10 and the recording medium 9 is reduced, so that optical recording using near-field light is performed. In the reproducing apparatus, it is possible to perform a stable recording / reproducing operation in which the gap servo does not fail.

  Note that the shape of the conical portion 31b provided in the upper lens structure of the solid immersion lens 10 described above is not limited to the conical shape, and may be a pyramid shape. Similarly, the inverted cone shape of the skirt portion provided in the convex portion 32 of the lower lens structure may be an inverted pyramid shape. Further, the inclination angle θ of the inclined surface 11 provided in the conical portion 31 is set to an angle that does not interfere with the incident light of the laser. In the near-field optical recording / reproducing system for the magneto-optical recording medium, a magnetic field is required at the time of recording and / or reproduction. Therefore, a magnetic coil or the like is attached to a part of the objective surface of the solid immersion lens or its periphery. It may be configured.

In addition, as described above, the material of the solid immersion lens has a large refractive index, a large transmittance, and a small light absorption with respect to the wavelength of the laser light source equipped in the optical recording / reproducing apparatus and optical pickup apparatus to be used. Those are suitable as materials. For example, S-LAH79 (trade name) manufactured by OHARA INC. Which is a high refractive index glass, Bi ₄ Ge ₃ O ₁₂ , SrTiO ₃ , ZrO ₂ , which is a high refractive index ceramic, a high refractive index single crystal material, HfO ₂ , SiC, KTaO ₃ , diamond and the like are suitable.

  Further, it is desirable that these lens materials have an amorphous structure or a cubic structure in the case of a single crystal. In the case where the lens material has an amorphous structure or a cubic structure, the etching rate and etching characteristics do not change depending on the crystal orientation, so that it is possible to use a known etching method or apparatus used for processing a semiconductor or the like.

  In addition, the solid immersion lens is molded by die-cut molding or by cutting and polishing a ball lens. Furthermore, for the processing of the condensing part provided at the tip of the convex part such as the conical shape of the solid immersion lens, that is, the flat part of the objective surface, a known etching method or apparatus used for semiconductor processing can be used. In particular, for processing a fine tip, for example, a focused ion beam processing method and a processing apparatus such as a focused ion beam processing observation apparatus FB-2100 (trade name) manufactured by Hitachi, Ltd. are used. preferable.

FIG. 1 is a schematic configuration diagram of an example of an optical recording / reproducing apparatus including an optical pickup device according to the present invention. FIG. 2 is a schematic configuration diagram showing a light incident mode on a recording medium in the optical pickup device according to the present invention. FIG. 3A is a schematic configuration diagram showing a gap between a recording medium and a head portion of an optical pickup device using near-field light. FIG. 3B is a diagram showing the relationship between the gap and the return light amount in the recording medium of the optical pickup device using near-field light. FIG. 4 is a schematic configuration diagram of an example of an optical recording / reproducing apparatus including the optical pickup device according to the present invention. FIG. 5 is a cross-sectional view showing an example of a solid immersion lens according to the present invention. FIG. 6 is a cross-sectional view showing another example of the solid immersion lens of the present invention. FIG. 7 is a cross-sectional view showing another example of the solid immersion lens of the present invention. FIG. 8 is a sectional view showing an example of still another embodiment of the solid immersion lens of the present invention. FIG. 9A is a schematic diagram showing a path when the dust D moves on the recording medium by an air flow. FIG. 9B is a plan view of the solid immersion lens used for explaining the direction in which the dust D enters the solid immersion lens. FIG. 10 is a cross-sectional view of the recording medium and the solid immersion lens used to explain the flow of air generated between the recording medium and the solid immersion lens. FIG. 11 shows the result of comparison between the solid immersion lens of this example and the tip cone type solid immersion lens in relation to the initial dust position and the position where the dust rolls up. FIG. 12 shows the result of comparing the solid immersion lens of this example with the tip cone type solid immersion lens in relation to the initial dust position and the position where the dust rolls up. FIG. 13 shows the result of comparing the solid immersion lens of this example with the tip cone type solid immersion lens in relation to the initial dust position and the position where the dust rolls up. 14A and 14B are cross-sectional views of a conventional solid immersion lens.

Explanation of symbols

  9 .. Recording medium (disc) 10.. Solid immersion lens (SIL) 11, 33.. Inclined surface 20.. Condensing part (objective surface) 31.. Upper lens structure 31. Structure, 32..Lower lens structure (convex part), 43..Drive unit, 44..Light detection unit, 45..Control unit, 47..Optical pickup device, .theta..tilt angle, c..light Shaft, D · Dust

Claims (3)

A solid immersion lens comprising an upper lens structure and a lower lens structure formed by a convex part having a condensing part ,
The upper lens structure includes an upper lens inclined portion that is inclined so as to narrow toward the convex portion ,
The lower lens structure includes a lower lens inclined portion connected to the upper lens inclined portion and formed to expand toward the objective surface of the light collecting portion . An optical pickup device comprising at least a light source and a condenser lens composed of a solid immersion lens and an optical lens;
The solid immersion lens includes an upper lens structure and a lower lens structure formed by a convex portion having a condensing part ,
The upper lens structure includes an upper lens inclined portion that is inclined so as to narrow toward the convex portion ,
The optical pickup device, wherein the lower lens structure includes a lower lens inclined portion that is connected to the upper lens inclined portion and is formed to expand toward the objective surface of the light collecting portion . At least a light source, a condensing lens composed of a solid immersion lens and an optical lens, an optical pickup device for condensing and recording light on an optical recording medium, and the condensing lens and optical pickup An optical recording / reproducing apparatus comprising drive control means for driving and controlling the apparatus,
The solid immersion lens includes an upper lens structure and a lower lens structure formed by a convex portion having a condensing part ,
The upper lens structure includes an upper lens inclined portion that is inclined so as to narrow toward the convex portion ,
The optical recording / reproducing apparatus, wherein the lower lens structure includes a lower lens inclined portion connected to the upper lens inclined portion and formed to expand toward the objective surface of the light collecting portion .

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