JP4025258B2 - Optical disc recording / reproducing apparatus and optical disc recording / reproducing method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an optical disc recording / reproducing apparatus and an optical disc reproducing / recording method, and in particular, an optical disc having a super-resolution effect, an optical disc recording / reproducing device for recording and reproducing information from the optical disc using the super-resolution effect, and The present invention relates to an optical disc recording / reproducing method.
[0002]
[Prior art]
In an optical disc on which a user can record and reproduce information, the information area on the optical disc is physically divided into sectors. These sectors are assigned addresses for each sector.
[0003]
In such an optical disc, when recording information, a light beam having a higher power level than when reading information is intensity-modulated, and this recording light beam is irradiated onto the optical disc. Further, at the time of reading information, a light beam having a constant power level lower than that at the time of recording is generated, and this reproducing light beam is irradiated onto the optical disk. More specifically, in a recording mode in which information is recorded in a designated sector on the disk, a recording material on the optical disk is irradiated with a laser beam with a relatively high recording power (Pw) having a pattern corresponding to the information to be recorded. Is causing a physical change. On the other hand, in a reading mode in which information recorded in a designated sector on the disk is reproduced, a relatively low reproduction power (Pr) is applied to the optical disk, and a physical change in the recording material of the optical disk is read as a change in the amount of reflected light.
[0004]
In general, in an optical disc, the reproduction power Pr is set to a sufficiently low power that does not cause a physical change in the recording material of the optical disc. Prior to recording or reproduction, during the seek operation in which the irradiation light beam is moved to the target sector, the address information provided in the form of pre-pits or groove wobbles in each sector is usually read out. Similarly, during this seek operation, the address information is read out with the light beam having the reproduction power Pr. Further, even in the idling mode during standby before shifting to the recording mode, the reading mode, or the seek operation mode, the irradiation light beam is focused on any one of the optical disks. Even in such a standby mode, the optical disk is irradiated with the light beam having the reproduction power Pr in the same manner. As described above, each sector on the optical disk is frequently irradiated with a light beam having a reproduction power even when recording information is not actually read out.
[0005]
In recent years, an optical disc having a super-resolution effect has been proposed as a method for recording and reproducing information at a higher density. In the recording / reproducing method using the super-resolution effect, information recorded with a size less than the resolution limit limited by the irradiation optical system is read using the super-resolution effect of the medium in the optical disk. It is. As an example of a recording / reproducing method using a super-resolution effect, a method using a phase change material as described in Non-Patent Document 1 for a mask layer, or an organic dye material as described in Non-Patent Document 2 There is a method of using for the mask layer. In these optical discs, a mask layer is provided on the light beam incident side of the information recording layer, and information is recorded / reproduced by the light beam transmitted through the mask layer on the information recording layer. Regardless of the material, by causing a thermal state change in the mask layer material within the irradiation spot, the light beam transmitted through the mask layer can be reduced to a spot diameter or less, which is below the resolution limit. Recording and playback are possible. Here, the change in the state of the former material corresponds to melting and solidification, and the change in the state of the latter material corresponds to a change in molecular structure. In order to read out information recorded at a high density by exerting a sufficient super-resolution effect. Requires a certain level of reproduction power. However, in general, the performance of these mask layer materials deteriorates as the state change is repeated many times.
[0006]
Furthermore, irradiation with a high intensity light beam also causes thermal damage to the information recording layer under the mask layer. That is, when high-intensity irradiation is repeated on these optical discs in order to read information by the super-resolution effect, there is a problem that the medium as the optical disc deteriorates and the reliability of recorded information is gradually lost.
[0007]
As a countermeasure for preventing the deterioration of the mask material or the information recording layer as described above, the method proposed in Patent Document 1 can be applied to still reproduction in which the same sector is repeatedly read. In the method disclosed in Patent Document 1, the information once read is stored in the buffer memory, and the information in the buffer memory is used without reading the information again from the sector. While the information is held in the buffer memory, the information in the buffer memory is used and information is recorded in a place other than the sector where the information is recorded, for example, an area other than the information area, so that the deterioration of the medium is not promoted. A light beam is irradiated. Further, in Patent Document 1, while the information is held in the buffer memory, the light beam is defocused to reduce the irradiation intensity on the optical disc so that the medium deterioration is not accelerated, or the light to be irradiated. A scheme in which the beam intensity is reduced is disclosed.
[0008]
As a method for optimizing the reproduction power of an optical disc having a super-resolution effect, there is a method disclosed in Patent Document 2. In this method, an optimum reproduction power is determined in advance, and this optimum reproduction power is first read out from a management information area called lead-in on the disc, and the reproduction power in the information recording area is set. In this method, information for setting the reproduction power is recorded in the lead-in at a low density that does not require super-resolution reproduction. Therefore, reading can be performed by irradiating the lead-in with a light beam having an appropriate power.
[0009]
[Patent Document 1]
JP2001-34944
[0010]
[Patent Document 2]
JP-A-7-73506
[0011]
[Non-Patent Document 1]
Yasuda et al .: Proceedings of the 5th Symposium on Phase Change Recording (1993) p1
[0012]
[Non-Patent Document 2]
M. Hatakeyama et al: Proceedings of PCOS'99, (1999) p26
[0013]
[Problems to be solved by the invention]
The method disclosed in Patent Document 1 in which information is not frequently read from a sector by using a buffer memory can be applied only to still reproduction in which the same sector is repeatedly read as described above. Effective only for playback. Since an optical disk as a medium is frequently irradiated with reproduction power other than when reading recorded information, there is a problem that deterioration of the mask material layer or the information recording layer cannot be suppressed.
[0014]
In Patent Document 2 that discloses a method for optimizing the reproduction power of an optical disk, even if the reproduction power is optimum, the medium deterioration is completely suppressed as long as the reproduction power can obtain a sufficient super-resolution effect. There are not always problems. That is, in the information recording area, there is also a problem that deterioration cannot be suppressed because the reproduction power is frequently irradiated other than when the recorded information is read out.
[0015]
As described above, when a reproducing power is increased to read information recorded at a high density with a sufficient super-resolution effect on an optical disc having a super-resolution effect, the deterioration of the medium is promoted and the recording is performed. There is a problem that the reliability of information decreases.
[0016]
An object of the present invention is to provide an optical disc and an optical disc recording / reproducing apparatus capable of improving the reliability of information recording / reproducing.
[0017]
[Means for Solving the Problems]
According to this invention,
An optical system that selectively generates light beams of the first, second, and third intensities and collects the light beams of the first, second, and third intensities at a resolution limit;
A mask layer that condenses the first or second intensity light beam to provide a super-resolution effect, and is provided under the mask layer, and information is recorded by the first intensity light beam that has passed through the mask layer. A recording layer on which information is reproduced by the light beam having the second intensity that has passed through the mask layer, and a plurality of tracks and a plurality of sectors in which each track is divided into reproduction recording units. A possible user information area, and track and sector address information giving areas in which the track and sector address information of the user information area given to each sector is recorded at a recording density lower than the user information area, An optical disc having
A control unit that controls generation of the light beam, wherein a light beam having a first intensity is generated from the optical system in a recording mode to record information on the recording layer, and a second light is output from the optical system in a reproduction mode; A seek mode during a seek operation for generating a light beam of a certain intensity to reproduce information from the recording layer and moving the light beam to a target sector, and a recording / reproduction device prior to the recording, reproduction and seek mode. A control unit that generates a light beam of a third intensity from the optical system in an idle ring mode that is maintained in a standby state, and searches the address information addition region with the light beam of the third intensity during the seek operation; ,
The second light beam from the optical disc is detected and converted into user information, and the third-intensity light beam from the address information addition area is detected in the seek mode to detect track and sector address information. A playback processing unit for converting to
An optical disc recording / reproducing apparatus is provided.
[0018]
Moreover, according to this invention,
A mask layer in which the first or second intensity light beam is condensed to give a super-resolution effect, and the third intensity light beam is condensed at the resolution limit, and the mask layer is provided below the mask layer. A recording layer in which information is recorded by the light beam having the first intensity passing through the mask and information is reproduced by the light beam having the second intensity passing through the mask layer, and a plurality of tracks and each track are reproduced and recorded. A plurality of sectors divided into units, and a user information area in which user information can be recorded / reproduced, and a track and sector address information of the user information area assigned to each sector at a recording density lower than that of the user information area Address information addition area of recorded track and sector,
In a method of recording and reproducing information from an optical disc having
In the recording mode, the first intensity light beam is generated to record information on the recording layer, and in the reproduction mode, the second intensity light beam is generated to reproduce information from the recording layer, A third intensity from the optical system in a seek mode during a seek operation for moving the light beam to a target sector and an idle ring mode in which the recording / reproducing apparatus is maintained in a standby state prior to the recording, reproduction, and seek modes. And the address information addition area is searched with the light beam of the third intensity during the seek operation,
The second intensity light beam from the optical disc is detected and converted into user information, and in the seek mode, the third intensity light beam from the address information addition area is detected to detect the track and sector. An optical disc recording / reproducing method for converting into address information is provided.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
An optical disc and an optical disc recording / reproducing apparatus according to embodiments of the present invention will be described below with reference to the drawings.
[0020]
FIG. 1 is a plan view schematically showing the structure of an information area on an optical disc according to a first embodiment of the present invention, and FIG. 2 is a schematic cross-sectional view along the line AA shown in FIG. It is.
[0021]
As shown in FIG. 1, the optical disc is provided following a prepit header area 2 in which a prepit header 6 in which address information is recorded and the prepit header area 2 is recorded, and a user can record information. A user information recording area 4 is provided. The user information recording area 4 is provided with grooves 10 and lands 12 as tracks, and user information is recorded in the grooves 10 and lands 12 as tracks. Each track is divided into sectors, which are physical recording units. Within the sector, address information of the track and sector is given at the head of the track, followed by this address information, followed by the user information recording area of the sector. 4 is provided.
[0022]
In the user information recording area 4, as shown in FIG. 2, a base layer 22 is formed on a light-transmitting substrate 20, for example, a polycarbonate resin substrate 20, and a mask layer 24 is formed on the base layer 22. Yes. A recording layer 26 is formed on the mask layer 24, and a reflective layer 28 is further formed on the recording layer 26. A protective layer 30 is formed on the reflective layer 28. The mask layer 24 is referred to as a so-called variable light transmittance medium. When the light beam 32 is irradiated to the light transmittance variable medium of the mask layer 24 through the substrate 20 and the base layer 22, the light beam 32 is irradiated. The temperature in the portion within the beam spot is increased. The portion where the temperature is raised becomes light transmissive, and the other portion where the temperature does not rise becomes a mask. As a result, a so-called disk super-resolution effect occurs, and a light beam smaller than the irradiation spot diameter passes through the transparent portion of the mask layer 24 and is irradiated onto the recording layer 26. Therefore, a light beam having a smaller diameter than the beam spot formed on the optical disk by the light beam condensed by the objective lens (not shown) is directed onto the recording layer 26. In the recording mode, a recording mark is formed by the spot of this light beam, and in the reading mode, the light beam is modulated by the recording mark and returned to the objective lens. In other words, in a disc on which information is recorded using the super-resolution effect, the user information is recorded on the recording layer by a mark having a dimension not larger than the resolution limit limited by the irradiation optical system shown in FIG. 26 is recorded with high density.
[0023]
In an optical disk using the super-resolution effect, in order to read out user information, it is necessary to irradiate with reproduction power that can obtain a sufficient super-resolution effect. On the other hand, the address information recorded in the pre-pit header area has dimensions larger than the resolution limit limited by the irradiation optical system, and is recorded as pre-pits at a lower density than the user information. Therefore, when reading the address information, it is unnecessary to irradiate the reproduction power that can obtain the super-resolution effect.
[0024]
FIG. 3 is a block diagram schematically showing the configuration of an optical disc recording / reproducing apparatus to which the present invention is applied. As shown in FIG. 3, the optical disc 201 is rotated at a predetermined speed by a motor 202. When recording information on the optical disc 201 and reproducing information from the optical disc 202, a light beam is directed from the optical head 203 to the optical disc 202. That is, the laser 110 in the optical head 203 is controlled by the light source control system 204 to generate a recording or reproducing light beam with a predetermined intensity. This light beam is directed to the objective lens 205 via the collimator lens 112 and the beam splitter 114 arranged in the incident system optical path, and is focused toward the desired track by the objective lens 205, and the desired beam in the track is collected. Sectors are searched.
[0025]
A drive system 206 is provided to always focus the light beam on a desired track and to follow the track. The drive system 206 performs focus control and tracking control by individually moving the objective lens 205 along the optical axis and moving the entire optical head 203.
[0026]
On the other hand, the reflected light beam reflected by the optical disc 201 is returned to the optical head 203 through the objective lens 205, separated from the optical path of the incident light beam by the beam splitter 114 in the optical head 203, and directed to the photodetector 116. Then, the light is condensed by the projection lens 118 and detected by the photodetector 116. The detection signal from the photodetector 116 is output to the reproduction system 207 and converted into a reproduction signal. The reproduction system 207 can process any information of user record information recorded with marks and address information recorded with prepits as a reproduction signal.
[0027]
When the address information is a pre-pit as in the optical disc shown in FIG. 1, the address information is read, and the user record information specified by this address information is read next. Accordingly, the address information and the user record information are read out with time separation. The address information is output to the address information processing system 209, the user record information is output to the user information processing system (208), and the address information and the user record information are the user information processing system 208 and the address information processing system, respectively. Signal processing is performed at 209.
[0028]
Since the user recording information and the address information have different recording densities, the frequency of the reproduced signal is different and the processing is also different.
[0029]
The processing and each part of the recording or reproduction information described above are executed under the control of the controller 210.
[0030]
FIGS. 4A to 4C are graphs showing the difference in the power level of the light beam directed to the optical disc in the information recording mode, the information reading mode, and the seek or idle mode in the apparatus shown in FIG. In FIG. 4, the vertical axis represents the irradiation power of the light beam directed to the optical disc 201, and the horizontal axis represents the irradiation time of the light beam.
[0031]
In the information recording mode, that is, when user information is recorded in a designated sector on the optical disc 201, a recording light beam whose intensity is modulated in accordance with the information to be recorded is applied to the optical disc 201 as shown in FIG. Irradiated towards. This recording light beam has a pattern corresponding to the information to be recorded and has a relatively high recording power (Pw). By this recording light beam, a recording mark is recorded by causing a physical change in the recording layer 26 in the user information recording area 4.
[0032]
In the information read mode, that is, when information recorded in a designated sector on the disc is reproduced, a substantially constant reproduction power is applied to the recording layer 26 in the user information recording area 4 as shown in FIG. A reproduction light beam having (P2) is irradiated. The reproduction light beam has its reflection intensity modulated by a recording mark causing a physical change in the recording layer 26 portion of the optical disk, and the modulated light beam is read as reproduction information.
[0033]
Here, in order to obtain a sufficient super-resolution effect, it is necessary to set the reproduction power P2 to be high to some extent. However, when the light beam having the reproduction power P2 repeatedly irradiates the same sector many times, the medium deteriorates and the reliability of recorded information may be gradually lost. Therefore, in the reproducing apparatus to which the present invention is applied, the necessary and sufficient power P2 is given to the reproducing light beam only when the information recorded from the user information recording area 4 is read from the disc in the reading mode. Yes.
[0034]
State other than information recording and recording information reading, that is, a seek operation (referred to as a seek mode) in which the irradiation light beam is moved to the target sector prior to recording or reproduction, and an idling state in which these operations are on standby In (referred to as idling mode), the optical disc 201 is irradiated with a light beam having a power P1 lower than the power P2 as shown in FIG.
[0035]
As described above, the address information is recorded at a lower density than the user information, so that the super-resolution effect is not necessary for reading. Therefore, during the seek operation, the address information provided for each sector can be read in order to know the positional relationship between the current position of the irradiation light beam and the target sector. Similarly, in the user information recording as shown in FIG. 4A and in both the user information reproduction modes as shown in FIG. The effect is unnecessary. Therefore, the reproduction light beam having the power P1 is applied to the prepit header portion.
[0036]
The above-described switching of the light beam power will be described with reference to the flowchart shown in FIG. Here, the light source control system 204 shown in FIG. 3 is under the control of the controller 210, and the control operation shown in FIG. 5 is executed by the controller shown in FIG.
[0037]
When the apparatus shown in FIG. 3 starts to operate (step S1), the user first sets a reading mode or a recording mode by an input device (not shown). In setting this mode, the sector in which the information is stored is specified. That is, in the reading mode, the last sector is specified from the first sector to be read, or in the recording mode, the last sector is specified from the first sector to be written. Next, the intensity of the light beam is set to the reproduction power P1 (step S2). Focus and tracking control is executed using the light beam having the reproduction power P1, and the seek operation is started following the seek operation command (step S3). Accordingly, the track is tracked with the light beam having the reproduction power P1, and the target sector is searched (step S4). In this seek mode, only the prepit area is searched for with the light beam having the reproduction power P1. If the target sector is not searched, the seek operation is continued. When the target sector is searched from the pre-pit area, it is determined whether the reading mode is set (step S5). If it is not the reading mode, it is determined whether the recording mode is set (step S6). If it is not the reading mode, the user is requested to set the mode (step S7), and the process returns to step S2.
[0038]
In the reading mode, the power of the reproduction light beam is set to the power P2 (step S8), and the reproduction light beam having the power P2 is irradiated to the user recording area and the user recording information is utilized using the super-resolution effect. Is searched. Accordingly, the user record information is read out in units of sectors (step S9).
[0039]
In step S6, when the recording mode is set, the power is set to the recording mode power PW (step S10), and the recording light beam having the power PW is irradiated to the user recording area and the user is utilized using the super-resolution effect. Information is recorded. Accordingly, the user record information is recorded on a sector basis (step S11).
[0040]
When the reproduction or recording in the sector unit is completed, it is determined whether the sector is the last sector where information is to be reproduced or the last sector where information is to be recorded (step S12). If it is the last sector, the process is terminated (step S13). If it is not the last sector, the process returns to step S4 and the above-described process is executed.
[0041]
As described above, in the optical disc recording / reproducing apparatus shown in FIG. 3, information is recorded or recorded information is reproduced after the irradiation light beam is sought to the target sector in accordance with a user request. The controller 210 controls the intensity of the irradiated light beam as shown in FIG. 4 with respect to the light source control system 204 in accordance with the recording mode, reading mode, seek, and idle mode. Therefore, irradiation of high reproduction power onto the optical disc 201 can be minimized, and deterioration of the medium material of the optical disc 201 can be reduced.
[0042]
FIG. 6 is a plan view schematically showing an enlarged part of an optical disk according to the second embodiment of the present invention. In the optical disc shown in FIG. 6, the prepit header representing the address information is not provided, and the address information is recorded in the wobbling of the groove, which is a tracking guide groove in which user information is recorded. The wobbling signal is recorded at a sufficiently low frequency, that is, at a low density in order to distinguish it from the user recording information. That is, as shown in FIG. 6, the groove 10 or land 12 as a track is not formed concentrically but is curved at a low frequency, and the curve is read out to be taken out as a wobbling signal. Specifically, the wobbling signal is included in the tracking signal corresponding to the difference signal read out by the detector 116, and the wobbling signal is separated in the reproduction system and converted into address information in the address information processing system 209. . In order to read out user record information in the user record information area 4, it is possible to read out the wobbling signal by analyzing the tracking signal even if the light beam has a low reproduction power, and the address information can be extracted from the wobbling signal. . That is, as in the first embodiment, the super-resolution effect is not necessary for reading the address information.
[0043]
FIG. 7 is a graph showing the irradiation power in each mode for the optical disk shown in FIG. Since the optical disk shown in FIG. 6 does not have a pre-pit header portion that represents address information, the user information recording mode shown in FIG. 7A and the user information reading mode shown in FIG. Unlike (a) and FIG. 4B, there is no period during which the light beam is irradiated with the power P1. In the user information recording mode and the user information reading mode, the address information is read as a wobbling signal during irradiation of the recording power Pw or the reproduction power Pr. Address information provided by wobbling differs from user record information in detection calculation, and is detected from a tracking signal, that is, a track direction differential signal. As shown in FIG. 7C, in the seek and idle mode, only the reproduction light beam having the power P1 is irradiated as in FIG. 4C. As described above, the address information provided by the wobbling can be read even during the irradiation of the reproduction light beam having the power P1. That is, also in this embodiment, irradiation with high reproduction power onto the optical disk can be minimized, and deterioration of the medium can be reduced.
[0044]
In the above embodiment, as a method of reducing the deterioration of the optical disk medium, the power applied to the optical disk is controlled to minimize the high reproduction power irradiation. As another embodiment, there is a method for controlling the condensing state of a light beam irradiated onto an optical disk. That is, when reading user information, the irradiation light is focused on the optical disk, and in the seek or idle state, a defocus state in which a focusing error is given to the condensing mechanism (a state where the objective lens 205 is not focused on the optical disk). Irradiate with. Even when the same reproduction power as that in the focused state is irradiated, in the defocused state, the power density irradiated on the optical disk is reduced, so that medium deterioration can be reduced. Therefore, the same effect as controlling the irradiation power can be obtained.
[0045]
In the above embodiment, the optical disk having the pre-pit header of FIG. 1 is illustrated as a land / groove recording system, and the optical disk having a wobble groove of FIG. 6 is illustrated as a groove recording system. The present invention is not limited to this, and as an inverse combination, it is obvious that the optical disk having the pre-pit header shown in FIG. 1 may be used as the groove recording system, and the optical disk having the wobble groove shown in FIG. is there. In addition, it is obvious that the address information can be realized even with the land pre-pit, the combined use of the pre-pit and the wobble groove, or the like.
[0046]
In addition, this invention is not limited to the said embodiment as it is, In an implementation stage, a component can be deform | transformed and embodied in the range which does not deviate from the summary.
[0047]
Moreover, various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, you may combine the component covering different embodiment suitably.
[0048]
【The invention's effect】
As described above, according to the present invention, it is possible to provide an optical disc and an optical disc recording / reproducing apparatus that improve the reliability of information recording / reproducing.
[Brief description of the drawings]
FIG. 1 is a plan view schematically showing the structure of an information area on an optical disc according to a first embodiment of the invention.
FIG. 2 is a schematic cross-sectional view taken along the line AA shown in FIG.
FIG. 3 is a block diagram schematically showing the configuration of an optical disc recording / reproducing apparatus to which the present invention is applied.
4A to 4C are graphs showing differences in power levels of light beams directed to an optical disc in an information recording mode, an information reading mode, and a seek or idle mode in the apparatus shown in FIG. .
5 is a flowchart for explaining a reproduction power setting operation in the optical disk recording / reproducing apparatus shown in FIG. 3;
FIG. 6 is a plan view schematically showing an enlarged part of an optical disc according to a second embodiment of the present invention.
7A to 7C are graphs showing the difference in power level of the light beam in the information recording mode, information reading mode, and seek or idle mode for the optical disc shown in FIG.
[Explanation of symbols]
4). . . 5. User information recording area, . . Pre-pit header, 10. . . Groove, 12. . . Land, 20. . . Substrate, 22. . . Underlayer 24. . . Mask layer, 26. . . Recording layer, 28. . . Reflective layer, 201. . . Optical disc, 202. . . Motor, 203. . . Optical head, 204. . . Light source control system, 205. . . Objective lens, 206. . . Drive system, 207. . . Reproduction system, 208. . . User information processing system 209. . . Address information processing system, 210. . . controller

Claims (7)

An optical system that selectively generates light beams of the first, second, and third intensities and collects the light beams of the first, second, and third intensities at a resolution limit;
A mask layer that condenses the first or second intensity light beam to give a super-resolution effect, and is provided under the mask layer, and information is recorded by the first intensity light beam that has passed through the mask layer. And a recording layer in which information is reproduced by the light beam having the second intensity that has passed through the mask layer, and a plurality of tracks and a plurality of sectors in which each track is divided into reproduction recording units. and user information area capable, and a track and sector address information addition area that has been recorded at a low recording density than the track and sector address information of the user information area is assigned for each of the sectors the user information area An optical disc having
A control unit that controls generation of the light beam, wherein a light beam having a first intensity is generated from the optical system in a recording mode to record information on the recording layer, and a second light is output from the optical system in a reproduction mode; A seek mode during a seek operation for generating a light beam of a certain intensity to reproduce information from the recording layer and moving the light beam to a target sector, and a recording / reproduction device prior to the recording, reproduction, and seek mode. A control unit that generates a light beam of a third intensity from the optical system in an idle ring mode that is maintained in a standby state, and searches the address information addition region with the light beam of the third intensity during the seek operation ; ,
The second light beam from the optical disc is detected and converted into user information, and the third-intensity light beam from the address information addition area is detected in the seek mode to detect track and sector address information. A playback processing unit for converting to
An optical disc recording / reproducing apparatus comprising:     2. The optical disc recording / reproducing apparatus according to claim 1, wherein a track is provided in the user information area, and the address information adding area includes a groove wobble in which the track is curved in accordance with the address information.     The control unit includes a focus control mechanism that focuses the light beam on the mask layer, and the control unit controls the focus control mechanism to focus the light beams having the first and second intensities on the mask layer. 2. The optical disk recording / reproducing apparatus according to claim 1, wherein the control means controls the focus control mechanism to defocus the light beam having the third intensity onto the mask layer.     The control unit includes a setting unit that sets the first, second, and third strengths, the third strength is set lower than the second strength, and the second strength is 2. The optical disc recording / reproducing apparatus according to claim 1, wherein the optical disc recording / reproducing apparatus is set lower than the first intensity. A mask layer in which the first or second intensity light beam is condensed to give a super-resolution effect, and the third intensity light beam is condensed at the resolution limit, and the mask layer is provided below the mask layer. A recording layer in which information is recorded by the light beam having the first intensity passing through the mask and information is reproduced by the light beam having the second intensity passing through the mask layer, and a plurality of tracks and each track are reproduced and recorded. comprising a plurality of sectors obtained by dividing the unit, and user information can be recorded and reproduced user information area, at a recording density lower address information of tracks and sectors of the user information area from the user information area is assigned for each of the sectors Address information addition area of recorded track and sector ,
In a method of recording and reproducing information from an optical disc having
In the recording mode, the first intensity light beam is generated to record information on the recording layer, and in the reproduction mode, the second intensity light beam is generated to reproduce information from the recording layer, object to the light beam moved to a seek operation during Shikumo de and the recording of the sector, in the idle ring mode to maintain the recording and reproducing apparatus prior to reproducing and seek mode to the standby state, the third intensity from the optical system And the address information addition area is searched with the light beam of the third intensity during the seek operation ,
The second intensity light beam from the optical disc is detected and converted into user information, and in the seek mode, the third intensity light beam from the address information addition area is detected to detect the track and sector. An optical disc recording / reproducing method for converting into address information. In the recording and reproducing modes, the first and second intensity light beams are focused on the mask layer, and in the seek mode and idle ring mode , the third intensity light beam is defocused on the mask layer. The optical disc recording / reproducing method according to claim 5 . The power of the light beam with the third intensity is set lower than the power of the light beam with the second intensity, and the power of the light beam with the second intensity is the power of the light beam with the first intensity. The optical disk recording / reproducing method according to claim 5 , wherein the optical disk recording / reproducing method is set to be lower.

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