JP2010287308A - Information recording method in multilayered structure recording medium - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an information recording method and an information recording and reproducing device for recording information by a recording method especially by laser beam recording, in an information recording device for performing recording and reproducing on an information recording medium. <P>SOLUTION: With respect to the direction to which a laser beam is incident, information is recorded in a direction opposite to that of a plurality of three-dimensionally arranged recording layers where the laser beam sequentially arrives so that fluctuation is caused only by a certain light quantity change of the laser beam passing through the plurality of recording layers without destroying the information recorded in the recording layers through which the laser beam passes. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an information recording / reproducing apparatus for recording / reproducing information on an information recording medium, and more particularly to an information recording method and information recording / reproducing apparatus for recording information by a recording method using laser light recording.

  As a technique for recording and reproducing information on an information recording medium using a laser beam, an optical disk device or the like has already been put into practical use, and one of the rewritable optical disk devices is reversible between crystal and amorphous. There is a phase change optical disk using state change. In order to obtain these two states, the information recording medium is heated to the melting point or higher by irradiating it with high power (recording power) and then rapidly cooled to make it an amorphous state, which is an intermediate power between the high power and the reproduction power. By irradiating (erasing power) and raising the temperature of the information recording medium to the crystallization temperature and then slowly cooling it, it becomes a crystalline state and can be overwritten by a single laser beam.

  Conventionally, regarding recording of information by the above-described recording method, as described in Non-Patent Document 1, a recording layer on which information is recorded is bonded to have two recording layers. This is a method of irradiating a laser beam in the direction of recording, and is not a recording method of recording from one direction. As for reproduction only for reading information, as described in Non-Patent Document 2, the reproduction layer to be reproduced is a three-dimensional two-layer structure, and the information is read from the side closer to the incident position of the laser beam, Thereafter, the information farther from the laser light incident position is read.

DVD Specifications for Rewritable Disc (DVD-RAM) Part 1 Physical Specifications Version 1.0 (PH-17) DVD Specifications for Read-Only Disc (DVD-ROM) Part 1 Physical Specifications Version 1.0 (PH-28 to PH-39)

  The above-mentioned prior art does not consider a recording method of a multilayer structure in which a plurality of recording layers in which information is stored is arranged three-dimensionally with respect to a method capable of recording information, and is recorded by recording information. There have been problems such as large fluctuations in the amount of laser light due to scattering and absorption when the laser light passes through the recording layer, and information on the already recorded recording layer being destroyed.

  Further, in a recording method in which a recording layer in which information is stored has a multilayer structure in which a plurality of three-dimensionally arranged recording layers are divided, and a recording area is subdivided, and rotation control of a recording medium is required according to the subdivided recording area By recording information on a recording layer having a multilayer structure as in the read-only information reading method, when information is recorded on the recording layer from the inner periphery to the outer periphery, the outer periphery is changed to the inner periphery. It is necessary to move the laser beam or the recording medium toward the target, and when the rotation is controlled by the M-CLV (Modified Constant Linear Velocity) method, the number of rotations needs to be increased by about twice. Since these operation times become very long, the time involved in recording and reproducing information is also long, and there is a problem that the information transfer rate is greatly reduced.

  SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems, and in a multi-layered recording method in which a plurality of recording layers in which information is stored is arranged three-dimensionally, by considering the order in which information is recorded, a laser It is an object of the present invention to provide an information recording method that suppresses time for moving light or a recording medium and rotation control time of the recording medium.

  In order to achieve the above object, the information recording method of the present invention irradiates an information recording medium with oscillated laser light, and the recording area on the information recording medium is physically different from the unrecorded portion of information. A recording medium that forms a recording portion and stores information, and has a multi-layer structure in which a plurality of recording layers in which information is stored is arranged three-dimensionally, and the recording area in the plane of each recording layer is subdivided In a recording method for recording information on a medium, when information is recorded on a recording medium in which the amount of laser light varies greatly due to scattering and absorption by recording information, the laser light is emitted with reference to the direction in which the laser light is incident. By recording information in reverse to the recording layers of information that are arranged in a plurality of three-dimensionally arrived sequentially, the recording information of the recording layer through which the laser beam passes is not destroyed and passes through the plurality of recording layers. Do It is obtained to be able to vary by only a certain amount of light caused by the.

  Further, the information is recorded in a certain recording area in the plane of each recording layer, and the recording area of each recording layer is completely recorded from the state where all the recording areas in the recording layer are recorded. By recording information in the recording area and sequentially recording information on the recording layers arranged in three dimensions, the rotation control time in the M-CLV (Modified Constant Linear Velocity) method can be suppressed. .

  According to the present invention, in recording on a recording medium having a multilayer structure, the recording information of the recording layer through which the laser beam passes is not destroyed, and only a certain amount of light change due to passing through the plurality of recording layers. Therefore, it is possible to record highly reliable information. In addition, since information can be recorded on the recording layer having a multilayer structure for each zone, the movement time of the light spot can be minimized, so that the transfer rate during information recording can be improved.

The block diagram which shows the information recording / reproducing apparatus structure in one Embodiment of this invention. The block diagram which shows the focus position detection method in the multilayer structure recording medium in one Embodiment of this invention. The figure which shows the information recording method in the multilayer structure recording medium in one Embodiment of this invention.

  Embodiments of the present invention will be described below. FIG. 1 shows an embodiment of the apparatus configuration of the present invention. Here, 1 is a laser, 2 and 4 are lenses, 5 is a recording medium, 12 and 13 are photodetectors, 15 is a reproduction circuit, 20 is a laser driver, 21 is a power monitoring circuit, 22 is a servo drive circuit, and 23 is A controller 24 represents a spindle drive circuit.

  The information recording / reproducing apparatus converts an optical head centered on the laser 1, a recording medium 5 for storing information, a recording processing system centered on the laser driver 20, and a reproduction signal obtained from the optical head into information. The reproduction processing system is centered on the reproduction circuit 15 that performs the above processing. The recording medium 5 includes a first recording layer 7, an intermediate layer 8, a second recording layer 9, and a protective layer 10 laminated on a substrate 6.

  The command and information data from the host are converted into a code string corresponding to the decoding of the command and the modulation and modulation method of the recording data by the controller 23 and transmitted to the laser driver 20. When adopting a recording method called M-CLV (Modified Constant Linear Velocity) method that changes the rotation speed of the recording medium for each zone and makes the recording density at the inner and outer circumferences substantially constant as a method of increasing the capacity Therefore, it is necessary to control the rotational speed of the spindle with high accuracy in accordance with the zone to be recorded / reproduced.

  The servo for controlling the position of the light spot for recording / reproducing information is a preamplifier 4 and a servo circuit by a cylindrical lens (not shown) arranged in front of the photodetector 12 and the photodetector (four divisions) 12. 18, a focus error signal and a track error signal can be obtained. The error signal is input to the controller 23, the servo signal is output from the controller 23 to the servo drive circuit 22, and the actuator 11 is controlled by the servo drive circuit 22. Thus, the position control of the light spot is performed.

  The high frequency superimposing circuit 19 is provided to reduce the laser noise caused by the laser 1, and the high frequency superimposing may be suspended at the time of recording / erasing from the viewpoint of the life of the laser.

  During reproduction, the laser 1 is oscillated at a low output and is incident on the recording medium 5. The reflected light from the recording medium 5 is incident on the photodetector 12 after the optical path is separated by the prism 3. After photoelectric conversion by the photodetector 12, the light is amplified by the preamplifier 14 and input to the reproduction circuit 15. The reproduction circuit 15 includes a waveform equalization circuit, an automatic gain control circuit, a binarization circuit, and the like, and an input reproduction signal is used as a binarization signal.

  The binarized signal from the reproduction circuit 15 is input to a PLL (Phase Locked Loop) 16 for self-clocking. The recovered clock synchronized with the binarized signal obtained by the PLL 16 and the binarized signal are input to the discrimination circuit 17 for data discrimination, and the resulting data discrimination signal is input to the controller 23. Data is demodulated.

  When recording information, a recording pulse train modulated in accordance with regular information data from the controller 23 is output to the laser driver 20. The laser driver 20 oscillates the laser 1 at a high output, and the light emitted from the laser 1 is converted into parallel light by the lens 2 and passes through the prism 3 and is converged on the recording medium 5 by the lens 4 in accordance with the code string. Record the recording mark.

  FIG. 2 shows a focus position detection method for a multilayer structure recording medium according to the present invention. When the recording medium 5 is set to the spindle 25, the lens 4 is moved from the substrate 6 toward the protective layer 10 in the management area 40 provided on the inner periphery or the outer periphery of the recording medium 5 to obtain the protective layer 10 of FIG. When the light spot passes through the first recording layer 7 and the second recording layer 9 as shown in the graph of the defocus amount and the focus error signal amplitude described on the lower side, the focus error signal amplitude is zero with a downward slope. become. The defocus ΔL between the two points is the defocus amount between the first recording layer 7 and the second recording layer 9, and this ΔL is stored in the controller 23, whereby the first recording layer 7 and the second recording layer are stored. The focal position of 9 can be freely changed.

  FIG. 3 shows an information recording method in the multilayer structure recording medium of the present invention. FIG. 3 shows a recording method in a zone n31 obtained by dividing the recording medium 5 in the radial direction, and shows a recording method called an M-CLV (Modified Constant Linear Velocity) method. In FIG. 3A, the light spot is moved to the start position of the zone n 31 of the second recording layer 9, and the rotation speed of the spindle 25 is controlled by the spindle drive circuit 24. After the rotational speed of the recording medium 5 is controlled, recording is started from the start position of the zone n31 of the second recording layer 9, and recording is performed up to the end position of the zone n31.

  Next, the actuator 11 is controlled by the servo drive circuit 22 in order to move the focal position by ΔL described in FIG. The light spot moves from the second recording layer 9 to the first recording layer 7, and further, the state in which recording is started by moving the light spot to the start position of the zone n31 of the first recording layer 7 is shown in FIG. And recording is performed up to the end position of the zone n31 of the first recording layer 7. Thereafter, as shown in FIG. 3 (c), the light spot is moved to the zone n + 1 32, the number of rotations of the spindle 25 is controlled by the spindle drive circuit 24, and the focal position is moved by ΔL described in FIG. The light spot is moved from the recording layer 7 to the second recording layer 9, and recording is started again from the start position of the zone n + 1 32 of the second recording layer 9.

  By recording information from the second recording layer 9 as described above, it is possible to accurately record information without suffering a large light amount fluctuation due to scattering and absorption of laser light in the first recording layer 7 that is not recorded. . Further, since information can be recorded on the first recording layer 7 and the second recording layer 9 for each zone, the rotation control time of the spindle 25 due to the change of the zone can be minimized.

  Furthermore, since the movement of the light spot during recording is only required to move within the zone, it is possible to keep the movement time to a minimum. Usually, the movement distance of the light spot in the CD size is about 30 to 40 mm, and an inexpensive movement mechanism consumes about 0.2 to 0.3 seconds. Therefore, if the zone is set to about 1 mm, a travel time of about 0.01 seconds is sufficient. Therefore, after information is recorded in all zones of the second recording layer 9, information is recorded on the first recording layer 7. Compared with this, the movement time of the light spot can be greatly reduced.

  In addition, when the scattering and absorption of the laser beam due to the recording of the first recording layer 7 are small, the focal position is not moved in the zone n + 1 32 shown in FIG. 3C, and the first recording in the zone n + 1 32 is performed. By starting recording of information from the layer 7 and recording information on the second recording layer 9 after the information recording on the first recording layer 7 is completed, the operation change of the information recording / reproducing apparatus accompanying the zone change is as follows: Only the rotation control of the spindle 25 is performed, and the transfer rate at the time of information recording can be improved.

  As described above, when the recording order is arbitrarily changed according to the characteristics of the recording medium, the recording order can be recorded in the management area 40 shown in FIG.

  DESCRIPTION OF SYMBOLS 1 ... Laser, 4 ... Lens, 5 ... Recording medium, 6 ... Board | substrate, 7 ... 1st recording layer, 8 ... Intermediate | middle layer, 9 ... 2nd recording layer, 10 ... Protective layer, 22 ... Servo drive circuit, 23 ... Controller 24 ... spindle drive circuit, 25 ... spindle, 31 ... zone n, 40 ... management area, 41 ... zone m.

Claims (6)

  An information recording medium is irradiated with an oscillated laser beam to form a recording part that is physically different from an unrecorded part of information in a recording area on the information recording medium. In a recording method for recording information on a recording medium having a multi-layer structure in which a plurality of recording layers to be stored are arranged three-dimensionally and a recording area in the plane of each recording layer is subdivided, the plane of each recording layer Information is recorded in a certain subdivision recording area, information is recorded in the subdivision recording area in the plane of each recording layer from the state where all the recording areas of each recording layer are recorded, An information recording method for a multilayer structure recording medium, wherein information is sequentially recorded on a plurality of three-dimensionally arranged recording layers.   The information recording method according to claim 1, wherein the information is recorded on a recording medium capable of recording information only once, and a plurality of three-dimensionally arranged laser beams sequentially reach with reference to the direction in which the laser beams are incident. An information recording method for a multi-layered recording medium, characterized in that information is recorded opposite to the information recording layer.   The information recording method according to claim 1, wherein information is recorded on a recording medium in which the amount of laser light varies greatly due to scattering and absorption by recording information, with reference to the direction in which the laser light is incident. An information recording method for a multi-layered recording medium, wherein information is recorded on the contrary to a plurality of three-dimensionally arranged information recording layers to which laser beams sequentially reach.   2. The information recording method according to claim 1, wherein the recording medium in which the recording area in the plane is subdivided is controlled to rotate by an M-CLV (Modified Constant Linear Velocity) method. When recording information in a certain subdivided recording area and recording information in a subdivided recording area in the plane of each next recording layer from a state where all recording areas of each recording layer are recorded, An information recording method for a multi-layered recording medium, wherein only the rotational speed of the recording medium is controlled.   2. The information recording method according to claim 1, wherein the information recording order is recorded in a predetermined area of the recording medium.   2. The information recording method according to claim 1, wherein the focal position of each recording layer of the multilayer structure recording medium is set in advance before the information is recorded in a predetermined area of the recording medium or an area for managing the recording information. An information recording method for a multi-layered recording medium, wherein the information is detected.

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