JP2000021022A - Optical disk and optical disk device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase an information transfer speed for recording/reproducing by a light in a near place without increasing a scanning speed. SOLUTION: The recording surface 1a of an optical disk 1 is provided with information areas 13 and tracking grooves 14 alternately arrayed to be extended in a disk peripheral direction T and a disk radial direction R. The information area 13 includes a plurality of information recording sections 15 arrayed in the disk radial direction R, each information recording section 15 being provided for recording/reproducing information by a light in a near place. In this case, while performing tracking by using the information area 13 and the tracking groove 14 as references, information recording/reproducing is carried out simultaneously by a light in the near place with respect to the plurality of information recording sections 15 included in the information area 13.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disk and an optical disk apparatus for recording or reproducing information on or from a recording surface of the disk by near-field light.
The present invention relates to an optical disk having an improved track configuration on a recording surface of an optical disk, and an optical disk device for such an optical disk.

[0002]

2. Description of the Related Art In a conventional general optical disk apparatus, information is recorded or reproduced by using propagating light. Therefore, information cannot be recorded or reproduced beyond the diffraction limit of light. The size of the recording mark is limited by the wavelength of the light.

[0005] Therefore, an optical disk device for recording or reproducing information using near-field light which is not limited to the diffraction limit has been proposed. When this near-field light is used, the range of irradiating the recording surface of the optical disk is determined by the size of the optical aperture of the light irradiation part regardless of the wavelength of the light source. Can be miniaturized, and higher-density information recording can be realized.

[0004]

However, in an optical disk apparatus using near-field light, the excitation efficiency of the light irradiating section is low, and the mechanical fragility of the sharpened light irradiating section (probe) is high. Therefore, it is necessary to perform scanning on the recording surface of the disk at a relatively low speed. Such a low scanning speed is a constraint in improving the information transfer speed in recording or reproduction using near-field light.

Among the limitations on the scanning speed, the mechanical fragility of the light irradiation section has been solved through research on a flat probe array using anisotropic etching of silicon. Regarding the improvement of excitation efficiency, research on sharpened optical probes (T.Yatsui e
t al: Appl.Phys.lett., vol.71, no.13, pp.1756 (1997))
Solutions are being pursued through such means.

However, at the present time, there has not been found any means that can simultaneously eliminate both of the above restrictions on the scanning speed and perform high-speed scanning on the recording surface of the disk. Therefore, it is an immediate task to increase the information transfer speed in recording or reproduction using near-field light without increasing the scanning speed on the recording surface of the disk.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and it is an object of the present invention to increase the transfer rate of information in recording or reproduction by near-field light without increasing the scanning speed on the recording surface of a disk. It is an object of the present invention to provide an optical disk and an optical disk device that can be used.

[0008]

A first means is an optical disk having a recording surface, wherein the recording surface extends in the disk circumferential direction and is alternately arranged in the disk radial direction and the information area and the tracking area. An optical disk, comprising: a plurality of information recording bands for recording or reproducing information by near-field light, the plurality of information recording bands being arranged in a disk radial direction; It is.

According to the first means, while performing tracking based on the information area and the tracking area, a plurality of information recording bands included in the information area are
At the same time, it is possible to record or reproduce information using near-field light. This makes it possible to increase the amount of information that can be recorded or reproduced at one time, as compared to the case where information is recorded or reproduced by near-field light in a single information recording band.

In the first means, the tracking area may have a structure of a groove or a projection formed on a recording surface, and information which can be photodetected separately from the information area. It may have the structure of a recorded information recording band.

The second means is an optical disk device for recording or reproducing information on or from a recording surface of an optical disk by near-field light. An optical disc comprising: a plurality of light irradiators for irradiating near-field light; a support member for supporting the light irradiators at a predetermined distance from a recording surface of the optical disc; and a light source for supplying light to each light irradiator. The distance between the plurality of light irradiating portions in a direction parallel to the recording surface is set to be larger than a half wavelength of the light of the light source.

According to the second means, information is simultaneously recorded or reproduced by near-field light on a plurality of portions (information recording bands) arranged in the radial direction of the disk on the recording surface of the optical disk. Becomes possible. In addition, since near-field light attenuates rapidly at a distance of about half the wavelength of light from the light source, the interval between a plurality of light irradiation units in a direction parallel to the recording surface of the disk is set to be larger than the half wavelength of light from the light source. Thus, crosstalk between adjacent information recording bands can be prevented.

[0013] The third means is the second means, further comprising a light detecting unit provided corresponding to each light irradiating unit and detecting reflected light from the recording surface of the optical disk, wherein each light detecting unit is The light irradiating section is arranged near the opposite side to the other light irradiating section adjacent to the corresponding light irradiating section.

According to the third means, in the second means, the reflected light from the information recording band corresponding to one light irradiation unit leaks to the light detection unit corresponding to another adjacent light irradiation unit. Therefore, it is possible to more effectively prevent crosstalk between adjacent information recording bands, particularly with respect to reflected light.

The fourth means is an optical disk having a recording surface extending in the circumferential direction of the disk and having information areas and tracking areas alternately arranged in the radial direction of the disk. An optical disc device of a second or third means for recording or reproducing information, wherein a tracking light irradiating unit provided to correspond to the tracking area, and irradiating the recording surface with light, Provided corresponding to the tracking light irradiation unit,
The apparatus further includes a tracking light detection unit that detects light reflected from the recording surface, and a tracking light source that supplies light to the tracking light irradiation unit.

In the fourth means, the light emitted from the tracking light irradiator may be configured to be near-field light emitted to the tracking area. In this case, it is preferable that the tracking area has a structure of an information recording band in which information detectable by near-field light is recorded separately from the information area.

In the fourth means, when a plurality of tracking light irradiators for irradiating near-field light are provided, from the same viewpoint as the light irradiator in the second means, the recording surface of the optical disk is provided. It is preferable that the interval between the plurality of tracking light irradiation units in the parallel direction is set to be larger than a half wavelength of the light of the tracking light source.

Also, in the fourth means, when a plurality of tracking light detecting sections are provided corresponding to the tracking light irradiating section, from the viewpoint similar to the case of the light detecting section in the third means, each tracking light detecting section is provided. It is preferable that the detection light detection unit is disposed near the corresponding tracking light irradiation unit on the side opposite to the other tracking light irradiation unit adjacent thereto.

[0019]

Next, an embodiment of the present invention will be described with reference to the drawings. 1 to 9 show an embodiment of an optical disk and an optical disk apparatus according to the present invention.

[First Embodiment] First, a first embodiment of the present invention will be described with reference to FIGS. FIG. 1 shows an optical disk 1 and an optical head 2 of an optical disk device for recording or reproducing information on a recording surface 1a of the optical disk 1 by near-field light.

As shown in FIG. 1, the substrate 1 of the optical disc 1
The recording surface 1a formed on the disk 1 has an information area 13 and a tracking groove (tracking area) 14 extending in the disk circumferential direction (track direction) T and alternately arranged in the disk radial direction R. I have. The information area 13 is an information recording band (track) 15 for recording or reproducing information using near-field light.
Book information band 15 is included.

Here, the configuration of the information area 13 will be described. The information area 13 is located on the disk substrate 11.
It comprises an information recording film 12 formed thereon by vapor deposition or the like. Examples of the material of the information recording film 12 include a phase change type material that changes the reflectance of the recording surface 1a by the thermal action of irradiation light, a magneto-optical material that also changes the rotation angle of the polarization of the reflected light by the thermal action, Alternatively, a photochromic material that changes the reflectance of the recording surface 1a by the optical action of irradiation light may be used.

Next, as shown in FIG. 4, the optical disk device comprises an optical head 2 disposed on the recording surface 1a of the optical disk 1, and a suspension for supporting the optical head 2 movably in the disk radial direction R. 6 is provided.

As shown in FIG. 2, the optical head 2 has a flying type slider (supporting member) 20 to which a fluid bearing effect is applied, which is generally used in a magnetic head for a hard disk. That is, a pair of rail portions 2 extending in the disk circumferential direction T are provided on both sides of the bottom surface of the slider 20.
0b, 20b are formed, and these rail portions 20b, 2b
Grooves 20a are formed between 0b. Also, at the rear end of the groove 20a in the disk circumferential direction T,
Optical device 21 for recording / reproducing by near-field light
Is provided.

The optical device 21 irradiates the information area 13 of the optical disc 1 with near-field light as shown in FIG. ) Is provided.

The optical device 21 is provided with each light irradiating section 26.
A light source 25 such as a semiconductor laser for supplying light to the
5 to a corresponding light irradiating section 26. Here, each light irradiation unit 2
Reference numeral 6 has a circular opening having a diameter (for example, several tens of nm) smaller than the wavelength of light from the light source 25.

As shown in FIGS. 3A and 3B, a plurality of light irradiation units 26 are arranged at intervals in the disk radial direction R corresponding to each information recording band 15 on the optical disk 1. Have been. Also, as shown in FIG. 3B, the distance d1, d2 between the light irradiators 26 in the direction parallel to the recording surface 1a of the optical disk 1 is larger than the half wavelength of the light from the light source 25. The light irradiation units 26 adjacent in the radial direction R are arranged at a predetermined interval in the disk circumferential direction T.

A large number of portions having the same shape as the light source 25, which are indicated by two-dot chain lines in FIG. 3A, indicate the arrangement of the light irradiating section 26 (and the corresponding light source 25) as described above. (The same applies to FIG. 8 referred later).

As shown in FIGS. 3A and 3B,
The optical device 21 includes a light detection unit 27 provided corresponding to each light irradiation unit 26. These light detection units 27 detect reflected light from the information area 13 (each information recording band 15) with respect to the near-field light emitted from the corresponding light irradiation unit 26. And FIG.
As best shown in (b), each light detection unit 27
The corresponding light irradiating section 26 is disposed near the opposite side to the other adjacent light irradiating section 26.

Next, as shown in FIG.
The pair of zero rails 20b are provided with a tracking light irradiation unit 22 and a tracking light detection unit 23 adjacent to the tracking light irradiation unit 22, respectively. The pair of tracking light irradiators 22 irradiate normal propagation light to both ends (see FIG. 1) of the information area 13 of the optical disc 1 (corresponding to the tracking grooves 14). I have. Further, the tracking light detection unit 23 detects reflected light from the recording surface 1a of the optical disc 1 with respect to the light emitted from the corresponding tracking light irradiation unit 22.

Next, recording of information on the recording surface 1a (information recording band 15) of the optical disk 1 by near-field light will be described. In the optical head 2 shown in FIG.
5 exits the optical waveguide 28 and enters the optical waveguide 28.
The light is guided inside and propagates to the openings of the respective light irradiation units 26. This propagating light is converted into a non-radiation field (evanescent field) by near-field light immediately after exiting the opening of each light irradiation unit 26. Information is written as a recording mark in the corresponding information recording band 15 by the thermal action or optical action by the non-radiation field.

Next, reproduction of information from the recording surface 1a (information recording band 15) of the optical disk 1 by near-field light will be described. In reproducing information, near-field light is emitted from the corresponding light irradiating section 26 to each information recording band 15 on which information is recorded in advance as a recording mark, and the reflected light is detected by the corresponding light detecting section 27. I do. Then, each light detection unit 27
A reproduction signal is generated in accordance with the intensity of the reflected light detected in step (1).

Next, using the tracking light irradiation section 22 and the tracking light detector 23 shown in FIG.
The tracking control by the so-called push-pull method will be described. First, when the slider 20 is not displaced from the information area 13, the propagation light emitted from the pair of tracking light irradiation units 22
Are reflected by the two side ends, and the intensity of the reflected light detected by the pair of tracking light detectors 23 becomes equal.

On the other hand, when the slider 20 is displaced to the right with respect to the information area 13, the light emitted from the right (left side in FIG. 2) tracking light irradiating section 22 is all or all. Part of the light is reflected by the tracking groove 14 on the right side of the information area 13, and the intensity of the reflected light detected by the right tracking photodetector 23 becomes relatively weak. When the slider 20 is displaced to the left with respect to the information area 13, all or a part of the light emitted from the tracking light irradiation unit 22 on the left side (the right side in FIG. 2) is used. The reflected light is reflected by the tracking groove 14 on the left side of the area 13 and the intensity of the reflected light detected by the photodetector 23 on the left side becomes relatively weak.

Accordingly, the pair of tracking light detectors 2
By controlling the position of the slider 20 based on the intensity difference of the reflected light detected by No. 3 so that this intensity difference becomes zero,
Tracking control can be performed.

In the recording / reproducing and tracking control of the information described above, the optical disk 1 is rotated, and the slider 20 scans the recording surface 1a in the disk circumferential direction T at a (relatively) predetermined scanning speed. It is performed in a state where

Next, the operation and effect of this embodiment having the above configuration will be described. According to the present embodiment, as described above, the information area 13 and the tracking groove 14
Information area 1 while tracking based on
It is possible to simultaneously record or reproduce information on a plurality of information recording bands 15 included in 3 using near-field light.

As a result, the amount of information that can be recorded or reproduced at one time can be increased as compared with the case where information is recorded or reproduced using near-field light in a single information recording band. Therefore, it is possible to increase the information transfer speed in recording or reproduction using near-field light without increasing the scanning speed for the recording surface 1a.

Further, the near-field light is rapidly attenuated at a distance of about half the wavelength of the light from the light source 25,
By setting the interval between the plurality of light irradiation units 26 in a direction parallel to a to be larger than a half wavelength of the light of the light source 25,
Crosstalk between adjacent information recording bands 15 can be prevented. Therefore, the recording or reproduction of the information can be made stable.

Further, since each light detecting section 27 is disposed near the corresponding light irradiating section 26 on the side opposite to the other adjacent light irradiating section 26, one light irradiating section 26 is provided. Can be prevented from leaking from the information recording band 15 corresponding to the light detection unit 27 corresponding to the other adjacent light irradiating unit 26. Crosstalk between them can be more effectively prevented. Here, a modified example of the present embodiment will be described. As shown in FIGS. 5 and 6, this modified example is an optical disc 1 having the tracking groove 14.
Instead, an optical disc 1 'having a tracking projection 16 is used.

Specifically, as shown in FIGS. 5 and 6,
The recording surface 1a 'of the optical disk 1' is provided with tracking projections (tracking areas) 16 instead of the plurality of tracking grooves 14 shown in FIG. In addition, the optical disk device includes an optical head 2 basically similar to that shown in FIGS. However, in this modified example, as shown in FIG. 6, the pair of rail portions 20b of the optical head 2 and the bottom surfaces (so-called ski surfaces) of the rails 20b are respectively provided with the tracking protrusions 1.
The scanning is performed in a state where the scanning is in contact with the reference numeral 6.

In this case, the optical device 2 of the optical head 2
1, the distance between the opening of each light irradiation unit 26 and the surface of the information area 13 (information recording film 12) of the optical disc 1 'is a half wavelength of the light of the light source 25, which is a distance where near-field light attenuates. It is kept at a smaller distance. As a result, the near-field light N emitted from the opening of each light irradiation unit 26 reaches the surface of the information area 13 (information recording film 12) with sufficient intensity, and the information recording band on the information area 13 It is possible to record information as a recording mark on the reference numeral 15. (The same applies to the optical disc and the optical disc apparatus shown in FIGS. 1 to 4). [Second Embodiment] Next, FIGS. 7 to 9 show a second embodiment of the present invention. Will be described. The present embodiment is different from the first embodiment in that the optical disk 3 shown in FIG. 7 is used in place of the optical disk 1 and an optical disk device having an optical head 4 as shown in FIG. Unlike the first embodiment, the other structure is substantially the same as the first embodiment shown in FIGS.

More specifically, first, as shown in FIG. 7, the recording surfaces 3a formed on the substrate 31 of the optical disk 3 extend in the disk circumferential direction T and are arranged alternately in the disk radial direction R. Area 33 and a tracking information recording band (tracking area) 34. The information area 33 is an information recording band 35 for recording or reproducing information by near-field light, and includes a plurality of (four in this case) information recording bands 35 arranged in the disk radial direction R. Contains.

In this case, the information area 33 and the tracking information recording band 34 are both constituted by the information recording film 32 formed on the substrate 31 by vapor deposition or the like. It has a structure in which light-detectable information is recorded separately from the information area 33. The material of the information recording film 32 may be the same as the material of the information recording film 12 of the first embodiment.

Next, as shown in FIG. 8, the optical head 4 of the present embodiment has a slider 20 similar to that of the first embodiment.
And an optical device 41 replacing the optical device 21 of the first embodiment. The optical device 41 has a tracking light irradiation unit 51 and a tracking light detection unit 52 that use near-field light in addition to the optical device 21 of the first embodiment. That is, the optical head 4 of the present embodiment uses a tracking light using near-field light provided in the optical device 41 instead of the tracking light irradiation unit 22 and the tracking light detection unit 23 of the first embodiment. An irradiation unit 51 and a tracking light detection unit 52 are provided.

Specifically, as shown in FIGS. 8 and 9,
The optical device 41 is provided with a pair of tracking light irradiators 51 that irradiate near-field light to the tracking information recording bands 34 on both sides of the target information area 33.

Further, as shown in FIG.
Includes a light source 50 such as a semiconductor laser that supplies light to each tracking light irradiation unit 51, and an optical waveguide 58 that propagates light from each light source 50 to the corresponding light irradiation unit 51. Each of the tracking light irradiation units 51 has a circular opening having a diameter (for example, several tens of nm) smaller than the light wavelength of the light source 50, similarly to the light irradiation unit 26.

The optical device 41 includes a tracking light detecting section 52 provided adjacent to each tracking light irradiating section 51. These tracking light detection units 52 detect reflected light from the tracking information recording band 34 with respect to the near-field light emitted from the corresponding tracking light irradiation unit 51.

Here, the tracking light irradiation section 51
The tracking control using the tracking photodetector 52 will be described. The near-field light emitted from the pair of tracking light irradiation units 51, 51 is reflected by the tracking information recording bands 34 on both sides of the target information area 33. The reflected light is detected by the pair of tracking photodetectors 52, 52, and a signal for tracking control (hereinafter, referred to as a "tracking signal") corresponding to the information recorded in the tracking information recording band 34. obtain.

In this case, the slider 20 is moved to the information area 33.
, The intensity of the tracking signal corresponding to the pair of tracking photodetectors 52, 52 becomes equal. On the other hand, when the slider 20 is displaced in the left or right direction with respect to the information area 33, the intensity of the tracking signal corresponding to the tracking photodetector 52 on the left or right side is relatively weak. Become.

Accordingly, the pair of tracking light detectors 5
The tracking control can be performed by controlling the position of the slider 20 based on the pair of tracking signal intensity differences corresponding to the signals 2 and 52 so that the intensity difference becomes zero.

The recording and reproduction of information on the recording surface 3a (information recording band 35) of the optical disk 3 by the near-field light and the scanning on the recording surface 3a by the slider 20 are the same as those in the first embodiment. The same is true.

Next, the operation and effect of this embodiment having the above configuration will be described. According to the present embodiment, while tracking is performed based on the tracking information recording band 34 as described above, information is simultaneously recorded on the plurality of information recording bands 35 included in the information area 33 by near-field light. Alternatively, reproduction can be performed.

As a result, as in the case of the first embodiment, the amount of information that can be recorded or reproduced at one time can be reduced as compared with the case where information is recorded or reproduced by near-field light on a single information recording band. Recording surface 3
The transfer speed of information in recording or reproduction by near-field light can be increased without increasing the scanning speed for a.

Here, a modified example of the present embodiment will be described. In this modification, as shown by a two-dot chain line in FIG. 9, tracking light irradiation units 51b and 51c for irradiating near-field light are added to the left and right of each tracking light irradiation unit 51 in the optical device 41. In addition, tracking light detectors 52b and 52c for detecting respective reflected lights are added corresponding to the tracking light irradiators 51b and 51c.

That is, in this modified example, three tracking light irradiators 51, 51b, 51c and three tracking light detectors 52, 52b, 52c correspond to the respective tracking information recording bands 34. Is provided. In this case, the tracking control is performed by using the push-pull method as described in the first embodiment, by associating the tracking light irradiation units 51b and 51c with the left and right sides of each tracking information recording band 34.

According to this modified example, the weakness of the signal intensity when the near-field light weaker than the normal propagation light is used for tracking can be compensated for, and the reliability of tracking can be improved.

In this case as well, from the same viewpoint as the distance between the light irradiation units 26 described in the first embodiment, a plurality of tracking light irradiation units 51 in a direction parallel to the recording surface 3a of the optical disc 3 are used. , 51b, 51c are larger than a half wavelength of the light of the light source 50.

In addition, from the same viewpoint as the arrangement of the light detecting unit 27 described in the first embodiment, each of the tracking light detecting units 52, 52b, 52c includes the corresponding tracking light irradiating unit 51, 51b, The tracking light irradiating units 51, 51b, and 51c are arranged near the opposite side of the adjacent tracking light irradiation units 51, 51b, and 51c.

[0060]

According to the present invention, the recording or reproduction of information by the near-field light is simultaneously performed on a plurality of information recording bands included in the information area while performing tracking based on the tracking area. Becomes possible. This makes it possible to increase the amount of information that can be recorded or reproduced at one time, as compared to the case where information is recorded or reproduced by near-field light in a single information recording band. Therefore, it is possible to increase the information transfer speed in recording or reproduction using near-field light without increasing the scanning speed on the recording surface.

Further, according to the present invention, it is possible to simultaneously record or reproduce information with a near-field light on a plurality of portions (information recording bands) arranged in the disk radial direction on the recording surface of the optical disk. It becomes possible. In addition, since near-field light abruptly attenuates at a distance of about a half wavelength of the light of the light source, the interval between the plurality of light irradiation units in a direction parallel to the recording surface of the disk is set to be larger than the half wavelength of the light of the light source. Thereby, crosstalk between adjacent information recording bands can be prevented. Therefore, without increasing the scanning speed on the recording surface, it is possible to increase the information transfer speed in recording or reproduction using near-field light, and
Recording or reproduction of the information can be made stable.

[Brief description of the drawings]

FIG. 1 is an essential part perspective view showing a first embodiment of an optical disk and an optical disk apparatus according to the present invention.

FIG. 2 is a perspective view showing the optical head of the optical disk device shown in FIG. 1 from the bottom side.

3A is an exploded perspective view showing a structure of an optical device in the optical head shown in FIG. 2, and FIG. 3B shows an arrangement of a light irradiation unit and a light detection unit in the optical device shown in FIG. Plan view.

FIG. 4 is a perspective view showing the relationship between the entire optical disc and the optical head in the embodiment shown in FIG.

FIG. 5 is an essential part perspective view showing a modification of the optical disc and the optical disc apparatus shown in FIG. 1;

FIG. 6 is a vertical cross-sectional view around the optical head of the optical disk and the optical disk apparatus shown in FIG. 5;

FIG. 7 is an essential part perspective view showing a second embodiment of the optical disc and the optical disc apparatus according to the present invention;

8 is a perspective view showing the optical head of the optical disk device shown in FIG. 7 from the bottom side.

FIG. 9 is an exploded perspective view showing a structure of an optical device in a modified example of the optical head shown in FIG.

[Explanation of symbols]

1, 1 ', 3 Optical discs 1a, 1a', 3a Recording surface 13, 33 Information area 14 Tracking groove (tracking area) 16 Tracking protrusion (tracking area) 34 Tracking information recording band (tracking area) 15, 35 information recording band 2, 4 optical head 20 slider (supporting member) 21, 41 optical device 22 tracking light irradiation unit (for propagation light) 23 tracking light detection unit (for propagation light) 25 light source 26 light irradiation Unit 27 Light detection unit 50 Light source for tracking 51, 51b, 51c Light irradiation unit for tracking (for near-field light) 52, 52b, 52c Light detection unit for tracking (for near-field light) R disk radial direction T disk circumferential direction ( Track direction)

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Junichi Akiyama 1 Komukai Toshiba-cho, Saiwai-ku, Kawasaki-shi, Kanagawa F-term in the Toshiba R & D Center (reference) 5D029 WA01 WB02 WD10 5D090 AA01 CC12 DD01 DD05 FF11 GG07 GG10 GG11 5D118 AA00 BA01 BB02 BC09 BF02 BF03 CD03 5D119 AA10 AA22 AA24 BA01 EC44

Claims (4)

[Claims] 1. An optical disk having a recording surface, wherein the recording surface includes an information area and a tracking area extending in a disk circumferential direction and alternately arranged in a disk radial direction. An optical disc, comprising: a plurality of information recording bands for recording or reproducing information by near-field light, wherein the plurality of information recording bands are arranged in a radial direction of the disc. 2. An optical disk device for recording or reproducing information by a near-field light on a recording surface of an optical disk, wherein the optical disk device is disposed at least in a radial direction of the disk.
A plurality of light irradiators that irradiate near-field light to the recording surface of the optical disc; a support member that supports these light irradiators at a predetermined distance from the recording surface of the optical disc; and a light source that supplies light to each light irradiator An optical disc device, wherein an interval between the plurality of light irradiation units in a direction parallel to a recording surface of the optical disc is set to be larger than a half wavelength of light of the light source. 3. A light emitting unit is provided corresponding to each light irradiating unit.
The optical disc further includes a light detection unit that detects light reflected from the recording surface of the optical disc, and each light detection unit is disposed near a corresponding light irradiation unit on the side opposite to the other adjacent light irradiation unit. 3. The optical disk device according to claim 2, wherein: 4. An optical disk having a recording surface having an information area and a tracking area extending in the disk circumferential direction and alternately arranged in the radial direction of the disk, for recording information by near-field light on the recording surface. 4. The optical disc device according to claim 2, wherein the optical disc device is provided corresponding to the tracking area, and irradiates the recording surface with light. And a tracking light detecting unit for detecting reflected light from the recording surface, and a tracking light source for supplying light to the tracking light irradiating unit. 4. The optical disk device according to 2 or 3.