JP2006344323A - Information recording apparatus and information recording method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an information recording apparatus and an information recording method in which write-in speed of information with respect to an optical disk can be improved, regardless of the increasing output of a laser beam. <P>SOLUTION: The information recording apparatus 10 is for recording information in a rotating disk D, and the apparatus is provided with a beam irradiating means 40 for pre-heating for irradiating a first laser beam for temperature-rasing the disk D within a range of lower temperature than a fixed threshold, a beam irradiating means 30 for recording for irradiating a second laser beam for temperature-rasing the disk D to temperature of a fixed threshold or larger for a part to which the first laser beam is irradiated out of the disk D, and a control means 70 controlling irradiation of the laser beam from at least the beam irradiating means 30 for recording out of the beam irradiating means 40 for pre-heating and the beam irradiating means 30 for recording. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an information recording apparatus and information recording method for recording information on an optical disk or the like.

  There are various rewritable optical discs using a phase change recording method, such as CD-RW, DVD-RAM, and DVD-RW. In phase change recording optical disks, germanium / antimony / tellurium alloys are generally used as recording materials. This recording material makes it possible to perform a transition between a crystalline state and an amorphous state (specifically, an umbrella flip-flop state is generated). Therefore, in an optical disc, information can be rewritten using a change in physical properties (change in light reflectance, etc.) of the recording material caused by this transition.

  In such an optical disc, an increase in information writing speed is desired. In particular, even in the case of an optical disk, in a large-capacity optical disk such as a Blu-ray disk or HD-DVD, it is desired to increase the writing speed in accordance with the amount of information to be written. In addition, as a technical document for writing information on an optical disc, there is one disclosed in Patent Document 1.

JP 2004-171636 A (see abstract, paragraph number 0003, FIG. 1 and others)

  By the way, in the above-mentioned Patent Document 1, the laser beam is divided by the dividing means, and the power of the divided laser beam is controlled so that the erasing laser beam and the writing laser beam are moved back and forth. ing. However, such technical contents relate to so-called overwriting, and are not sufficient for speeding up writing.

  Here, even when the optical disk rotates at high speed, a method of emitting a high-power laser beam in a stable state is also conceivable so that writing with the laser beam can be performed satisfactorily. However, since there is a certain limit to increasing the output of the laser beam, this method has a certain limitation on the improvement of the writing speed. In addition, optical components also have a thermal limit, and from this thermal aspect, there is a limit to increasing the output of laser light.

  As described above, there is a certain theoretical limit to the writing speed of the optical disk from the power aspect of the laser beam and the thermal aspect of the optical component, and the solution is desired.

  The present invention has been made based on the above circumstances, and an object of the present invention is to provide an information recording apparatus and an information recording apparatus capable of improving the writing speed of information on an optical disk without increasing the output of laser light. Try to provide a method.

  In order to solve the above-described problems, the present invention provides an information recording apparatus for recording information on a rotating disc, wherein the temperature of the disc rises within a temperature range lower than a certain threshold value. Preheating beam irradiating means for irradiating a first laser beam for causing the first laser beam to irradiate a portion of the disk irradiated with the first laser beam at a temperature equal to or higher than a certain threshold value Among the recording beam irradiating means for irradiating the second laser beam for raising the temperature up to, the preheating beam irradiating means and the recording beam irradiating means, at least the laser beam is emitted from the recording beam irradiating means. Control means for controlling.

  In this case, the first laser beam is irradiated using the preheating beam irradiating means, so that the temperature at the irradiation spot of the disk rises within a temperature range lower than a certain threshold value. . Then, by irradiating the irradiation spot of the optical disk where the temperature rises with the second laser beam using the recording beam irradiating means, the temperature is increased to a certain threshold value or more, and information is recorded on the disk. Can be recorded.

  Here, by heating the disk once with the first laser light, it is possible to shorten the time for heating the disk with the second laser light. Thereby, the rotation of the disk can be increased, and the writing time can be shortened.

  In another invention, in addition to the above-described invention, the preheating beam irradiating means and the recording beam irradiating means output laser light from the same laser light output section, and an optical path of the laser light. A spectroscope is disposed in the middle of the laser beam. The spectroscope splits the laser light into a first laser beam and a second laser beam.

  In such a configuration, it is not necessary to provide separate laser beam output units for the preheating beam irradiation unit and the recording beam irradiation unit. For this reason, only one laser beam output unit need be provided, and the component cost can be reduced. Further, the installation space can be reduced and the optical pickup can be downsized as compared with the case where two laser light output units are provided.

  Furthermore, in another information recording method for recording information on a rotating disc, the first invention is for raising the temperature of the disc within a temperature range lower than a certain threshold. A preheating step for irradiating the laser beam, and a portion of the disk that has been irradiated with the first laser light in the preheating step to raise the temperature of the disk to a temperature equal to or higher than a certain threshold value. And a recording step.

  In such a configuration, the temperature of the irradiated spot of the disk rises within the temperature range lower than a certain threshold value due to the irradiation of the first laser beam on the disk by the preheating process. Then, by irradiating the irradiation spot of the optical disc on which the temperature has increased with the second laser beam in the recording process, the temperature of the disc is increased to a temperature equal to or higher than a certain threshold value, and information is recorded on the disc It can be recorded.

  Here, by heating the disk once with the first laser light, it is possible to shorten the time for heating the disk with the second laser light. Thereby, the rotation of the disk can be increased, and the writing time can be shortened.

  According to the present invention, it is possible to improve the writing speed of information on an optical disc without increasing the output of laser light.

(First embodiment)
Hereinafter, an information recording apparatus 10 according to a first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a diagram showing an outline of an optical system in an information recording apparatus according to an embodiment of the present invention.

  As shown in FIG. 1, the optical system 20 of the information recording apparatus 10 includes a recording beam irradiation unit 30, a preheating beam irradiation unit 40, and a light receiving unit 50. Among these, the recording beam irradiation means 30 includes a first laser beam output unit 31, a first collimator lens 32, a polarization beam splitter 33, a quarter wavelength plate 34, and a first objective lens 35. It has.

  In the recording beam irradiating means 30, the first laser beam output unit 31 is a portion for outputting a recording / reproducing laser beam. The first laser beam output unit 31 uses a laser oscillator (not shown) such as a semiconductor laser. The first collimator lens 32 is a part for adjusting the laser light output from the first laser light output unit 31 into predetermined parallel light. The polarization beam splitter 33 reflects only S-polarized light and makes it incident on the quarter-wave plate 34. At this time, the P-polarized light passes through the polarization beam splitter 33 as it is. Instead of the polarization beam splitter 33, a configuration using a half mirror may be adopted.

  Further, in the quarter wavelength plate 34, the phase of the incident laser beam is shifted by 90 degrees. Further, the first objective lens 35 irradiates a predetermined position of the recording film of the optical disc D with a laser beam emitted from the quarter wavelength plate 34 as a light beam having a predetermined diameter.

  When information is written on the recording film of the optical disc D, the laser beam is emitted from the first laser beam output unit 31, the first collimator lens 32, the polarization beam splitter 33, the quarter wavelength plate 34, the first objective. It is only necessary to pass through an optical path that sequentially passes through the lens 35. For this reason, in a type in which a configuration for writing information to the recording film of the optical disc D is at least provided, a configuration in which the polarization beam splitter 33 and the quarter wavelength plate 34 are omitted may be employed. . However, in the present embodiment, a general type information recording apparatus 10 that can both record and read information will be described. In the information recording apparatus 10, when reading information already recorded on the recording film of the optical disc D, after the laser beam is emitted to the recording film of the optical disc D through the optical path described above, Laser light reflected from the recording film passes through the first objective lens 35, the quarter-wave plate 34, and the polarization beam splitter 33.

  Here, the S-polarized laser light again passes through the quarter wavelength plate 34 to become P-polarized light, and this P-polarized light passes through the polarization beam splitter 33 as it is. Accordingly, the P-polarized laser light is incident on the light receiving unit 50, and the information recorded on the recording film of the optical disc D is read by converting the incident light into an electric signal. As the light receiving unit 50, various light receiving elements such as a photosensor and a photodiode can be used.

  The preheating beam irradiation means 40 has a configuration similar to that of the recording beam irradiation means 30 described above, and includes a second laser light output unit 41, a second collimator lens 42, a second objective lens 43, have. However, unlike the recording beam irradiation means 30, the preheating beam irradiation means 40 does not require reflection of laser light, and therefore has a configuration corresponding to the above-described polarization beam splitter 33 and the quarter wavelength plate 34. Absent.

  The first objective lens 35 of the recording beam irradiation means 30 and the second objective lens 43 of the preheating beam irradiation means 40 are both driven by the lens actuator 60. The lens actuator 60 includes, for example, a coil / magnet for performing focusing / tracking, and moves the first objective lens 35 and the second objective lens 43 by the generation of a magnetic force accompanying current conduction. Yes.

  The information recording apparatus 10 also has a control unit 70 corresponding to the control means. The control unit 70 includes a recording laser beam (corresponding to the second laser beam) from the first laser beam output unit 31 and a preheating laser beam (first laser beam) from the second laser beam output unit 41. The irradiation timing is controlled. That is, in FIG. 2, when the preheating laser beam is irradiated before the recording laser beam in the same track of the recording film of the optical disc D, the irradiation timing of the recording laser beam is set to It is necessary to delay in accordance with the rotation speed of the recording film.

  Here, it is assumed that the rotation speed of the track irradiated with the preheating laser beam / recording laser beam is V, and the distance between the irradiation spot of the preheating laser beam and the irradiation spot of the recording laser beam is L. , There is a time difference of T = L / V. For this reason, the control unit 70 irradiates the track with the recording laser beam with a delay of the time difference T after the irradiation with the preheating laser beam.

  In addition to the optical system 20, the information recording apparatus 10 includes a turntable 80 on which the optical disc D is mounted, a spindle motor 81 for rotating the turntable 80, and the like. The spindle motor 81 may be connected to the control unit 70 described above. Further, as another configuration, a rotational speed detection means for detecting the rotational speed of the turntable 80 may be provided.

  FIG. 3 shows the relationship between the temperature of the recording film of the optical disc D and time when the recording film of the optical disc D is irradiated with preheating laser light / recording laser light. FIG. 4 shows the relationship between the temperature and time of a conventional recording film that irradiates the recording laser beam without irradiating the preheating laser beam. As shown in FIG. 3, in the preheating zone where the preheating laser beam is irradiated, the recording film reaches the recordable temperature (the broken line portion in FIG. 3; this broken line portion corresponds to a certain threshold value). do not do. However, by irradiating the recording laser beam thereafter, the small first laser beam output unit 31 can exceed the recordable temperature with a small amount of power. Note that the time from the irradiation of the preheating laser beam to the irradiation of the recording laser beam is very short, and the temperature drop in the recording film of the optical disc D is small.

  Further, comparing FIG. 3 with FIG. 4, the time for the temperature to rise to a certain threshold after the start of the preheating laser beam irradiation is the time when the upper recording apparatus 10 of the present invention is used. The time t1 (see FIG. 3) is clearly shorter than the time t2 when the conventional information recording apparatus is used.

  A method for recording information on the optical disc D using the information recording apparatus 10 having the above configuration will be described below.

  In a state where the spindle motor 81 is driven and the optical disk D is rotating at a predetermined rotation speed, the control unit 70 causes the second laser beam output unit 41 to generate a laser beam for preheating. Send. Thereby, a laser beam having a predetermined output is output from the second laser beam output unit 41, and the laser beam is irradiated to the vicinity of a predetermined track in the recording film of the optical disc D as shown in FIG. .

  In the following description, a portion of the recording film of the optical disc D that is irradiated with the preheating laser beam is referred to as a preheating spot. Although the preheating spot has a certain diameter, since the optical disk D is rotated, the preheating spots appear to move sequentially on the recording film of the optical disk D when viewed relatively. This also applies to a recording spot described later. The direction in which the preheating spot and the recording spot to be described later move is indicated by an arrow in FIG.

  Here, the second laser beam output unit 41 is a portion that outputs a laser beam for raising the temperature of the recording film of the optical disc D to a temperature just before reaching the information writing threshold. Therefore, the preheating spot in the recording film of the optical disc D is heated to a temperature lower than the threshold value. That is, the predetermined part on the track is heated to a predetermined temperature that does not reach the threshold value in the time until the spot for preheating in the recording film of the optical disc D passes.

  After the preheating laser beam is irradiated, a predetermined portion of the portion irradiated with the preheating laser beam is irradiated with the recording laser beam. That is, the control unit 70 transmits a control signal for generating a recording laser beam to the first laser beam output unit 31. As a result, a laser beam with a predetermined output is output from the first laser beam output unit 31, and this laser beam is applied to the recording film of the optical disc D. As shown in FIG. 2, the portion of the recording film of the optical disc D that is irradiated with the recording laser light is called a recording spot.

  Here, the first laser beam output unit 31 is a portion that outputs a laser beam for raising the temperature of the recording film of the optical disc D to a temperature exceeding the threshold for writing information. In such a temperature rise, the laser beam for preheating has already been irradiated, and the recording laser beam is again irradiated to the portion where the temperature has increased to a predetermined level. Therefore, the recording spot in the recording film of the optical disc D is heated to a temperature exceeding the threshold value by irradiation with a recording laser beam having a relatively weak output.

  When the rotational speed of the optical disc D is fast, the temperature of the recording spot can be raised to a threshold value or higher even if the recording laser light is output as usual, and the recording film of the optical disc D can be increased. Fully writable. Further, the temperature of the recording film of the optical disc D is not limited to the case where it is raised to a temperature exceeding the threshold value for writing information, but the temperature of the recording film may be heated to a temperature equal to the threshold value. good.

  According to the information recording apparatus 10 having such a configuration, the preheating laser beam is irradiated onto the recording film of the optical disc D, and then the preheating spot is irradiated with the recording laser beam. Thereby, it is possible to shorten the time for writing information to the recording film of the optical disc D. Further, by shortening the information writing time, the rotation of the optical disk D can be accelerated, and the information writing time can be shortened. Therefore, a large amount of information can be recorded on the recording film of the optical disc D at high speed.

  In addition, it is possible to improve the speed of writing information to the recording film of the optical disc D without increasing the output of the first laser beam output unit 31 and the like. Therefore, it is not necessary to provide a laser output unit corresponding to high output, and the cost can be reduced accordingly. In addition, since it is not necessary to cope with high output, the thermal limit of the optical component can be low.

(Second Embodiment)
Hereinafter, a second embodiment of the present invention will be described with reference to FIGS. In the present embodiment, the same components / members in the first embodiment will be described using the same reference numerals.

  As shown in FIG. 5, in the information recording apparatus 11 according to the present embodiment, the optical system 21 includes a first laser beam output unit like the optical system 20 of the information recording apparatus 10 according to the first embodiment described above. 31 and the second laser light output unit 41 are not configured to include the two laser light output units 31 and 41, and include only a single laser light output unit 31a.

  However, in the present embodiment, a spectroscope 90 is provided to split the laser light output from the laser light output unit 31a and passed through the collimator lens 32a. The laser beam output from the laser beam output unit 31a passes through the spectrometer 90, whereby the single laser beam is split into two laser beams.

  Here, as the spectroscope 90, there is one using a grating, a prism, or the like. Further, as the spectroscope 90, means for branching the laser beam may be used for current tracking correction.

  Note that each element in the subsequent optical path of each laser beam split from the spectroscope 90 is the same as that in the above-described first embodiment. That is, the information recording apparatus 11 of the present embodiment also includes the polarization beam splitter 33, the quarter wavelength plate 34, and the first objective lens 35. Then, one laser beam after being split from the spectroscope 90 passes through the polarization beam splitter 33, the quarter wavelength plate 34, and the first objective lens 35.

  In addition, the information recording apparatus 11 of the present embodiment includes the second objective lens 43, and the other laser beam dispersed by the spectroscope 90 passes through the second objective lens 43 and then the optical disc D. The recording film is irradiated.

  Here, as shown in FIG. 6, the spot for preheating has a larger spot diameter than the spot for recording. The spot diameter of the preheating spot is large enough to cover n bits. This size is such that the temperature of the recording spot irradiated with the recording laser light can be raised to a certain level or more. That is, when the laser beam output from one laser beam output unit is dispersed, the preheating spot and the recording spot are simultaneously present on the recording film of the optical disc D. In this case, the spot diameter of the preheating spot is adjusted to a sufficient size so as to prevent preheating leakage of the recording film of the optical disc D.

  In the information recording apparatus 11 having the above configuration, a preheating spot and a recording spot are simultaneously formed on the recording film of the optical disc D. In this case, since the spot diameter of the spot for preheating is sufficiently large, it is possible to prevent the occurrence of defective writing due to insufficient preheating of the portion when the recording laser beam is irradiated.

  Also in the present embodiment, it is possible to shorten the heating time of the optical disc D by the recording laser beam by once heating the optical disc D with the preheating laser beam. As a result, the rotation of the optical disc D can be accelerated, and the writing time can be shortened.

  In addition, as in the present embodiment, the recording beam irradiating means 30 and the preheating beam irradiating means 40 output laser light from the same laser light output unit 31a, and the optical path of this laser light. A spectroscope 90 is arranged in the middle. As a result, the spectroscope 90 splits the laser beam into a recording laser beam and a preheating laser beam. For this reason, it is not necessary to provide separate laser beam output units 31 and 41 for the recording beam irradiation means 30 and the preheating beam irradiation means 40. Therefore, only one laser beam output unit 31a needs to be provided, and the component cost can be reduced. Further, the installation space can be reduced as compared with the case where the two laser light output units 31 and 41 are provided, and the optical pickup can be downsized.

  Although the first embodiment and the second embodiment of the present invention have been described above, the present invention can be variously modified in addition to this. This will be described below.

  In each of the above-described embodiments, a case where only one preheating spot is provided has been described. However, the number of preheating spots is not limited to one, and two or more spots may be provided. FIG. 7 shows the situation in this case. In the case shown in FIG. 7, a spectroscope for dividing the preheating laser beam into two is newly required. The spectroscope may be the same as that described in the second embodiment. In the case shown in FIG. 7, the spot diameter of the above-mentioned preheating spot can be made smaller than those described in the above embodiments.

  Further, as shown in FIG. 8, a part of the preheating spot and the recording spot may be overlapped. Even in this case, since both the spot for preheating and the spot for recording are formed on the optical disc D, the temperature of the writing portion of the optical disc D is raised to some extent by irradiation with the laser beam for preheating, and the recording laser Information can be written to the optical disc D by light irradiation. It should be noted that partial overlap as shown in FIG. 8 can be realized by adjusting the optical path in the configuration described in each of the above-described embodiments. Partial duplication as shown in FIG.

  Further, as shown in FIG. 9, the center of the spot for preheating and the spot for recording may be substantially coincided, and the spot diameter of the spot for preheating may be made larger than the spot diameter of the spot for recording. Even in this case, it is possible to write information on the optical disc D by irradiating the recording laser beam while raising the temperature of the writing portion of the optical disc D to some extent by irradiating the pre-heating laser beam.

  In this case, the center of the second objective lens 43 in each of the above-described embodiments is adjusted by adjusting the focal length / lens magnification, and by adjusting the optical path, thereby matching the centers as shown in FIG. In this state, a state where two irradiation spots overlap is realized.

  Also, as shown in FIG. 10, the spot shape of the preheating spot is a horizontally long oval shape (here, the horizontally long state refers to a state in which the extension direction of the track is the long side direction of the ellipse) and the spot for recording The spot shape may be a vertically long oval shape (the vertically long shape here refers to a state in which the extending direction of the track is the short side direction of the ellipse). The spot shape can be made elliptical by adjusting the focal length using a cylindrical lens. In addition, an optical fiber having an elliptical core is provided, and laser light is emitted from this optical fiber. The spot shape may be an elliptical shape. In this case, since the preheating laser beam is irradiated in a horizontally long state, it is possible to improve the utilization efficiency of the laser beam output for preheating for preheating. Further, since the recording laser beam is vertically long, even when the track on the recording film of the optical disc D is slightly shifted, it is possible to reliably record the track at the recording site.

  Further, as shown in FIG. 11, the spot shapes of the preheating spot and the recording spot may both be a vertically long elliptical shape. In this case as well, as in the case shown in FIG. 11 described above, the spot shape can be made elliptical by adjusting the focal length using a cylindrical lens. It is also possible to provide an optical fiber that emits laser light from the optical fiber and make the spot shape elliptical. When configured in this manner, even when the track on the recording film of the optical disc D is slightly shifted, it is possible to reliably irradiate the track with laser light for preheating, and to the track at the recording site, It becomes possible to make it record reliably.

  In addition, as shown in FIG. 12, a preheating laser beam may be applied to a track in front of a track on which recording is performed. Also in this case, it is possible to realize a configuration in which the preheating spot as shown in FIG. 12 is located on the front circumference of the recording spot by adjusting the optical path. Even in this case, in view of the fact that the optical disk D rotates at a high speed, at the stage where the recording laser beam is irradiated, the heat from the preheating laser beam irradiation can remain sufficiently. It is possible to write information on the optical disc D by irradiating a recording laser beam while utilizing the heat.

  In each of the above-described embodiments, the case where the optical disk D is used as the disk has been described. However, the disk is not limited to the optical disk D, and information may be recorded using a magneto-optical disk as a disk.

  Furthermore, the recording beam irradiation means 30 and the preheating beam irradiation means 40 described above may employ various optical elements other than those described above. Other optical elements include various mirrors, lenses, prisms, diffraction gratings, wave plates, and the like. In the recording beam irradiation means 30 and the preheating beam irradiation means 40, the first collimator lens 32 and the second collimator lens 42, and the first objective lens 35 and the second objective lens 43 are shared. May be.

  Various drive devices such as CD-R / CD-RW drive, DVD-R / DVD-RW / DVD-RAM drive, Blu-ray disc drive, HD-DVD drive, etc. may be used as the information recording devices 10 and 11. Only the optical pickup portion used for each of these drives may be used as the information recording device. When only the optical pickup portion is used as the information recording apparatus, the turntable 80, the spindle motor 81, etc. are removed from the information recording apparatuses 10 and 11 described above. In addition, various types of electrical equipment (for example, a DVD recorder, a personal computer, a digital video camera, a digital camera, etc.) incorporating the above-described various drives may be used as the information recording apparatuses 10 and 11.

  The information recording apparatus and information recording method of the present invention can be used in the field of electrical equipment.

It is the schematic which shows the structure centering on the optical system of the information recording device which concerns on the 1st Embodiment of this invention. FIG. 2 is a diagram showing an irradiation spot of a laser beam on a predetermined track of an optical disc when the information recording apparatus of FIG. 1 is used. It is a figure which shows the relationship between time and temperature rise when irradiating a laser beam to the recording film of an optical disk using the optical system of the information recording device which concerns on the 1st Embodiment of this invention. It is a figure which shows the relationship between time and temperature rise when irradiating the laser beam to the recording film of an optical disk using the optical system of the conventional information recording device. It is the schematic which shows the structure centering on the optical system of the information recording device which concerns on the 2nd Embodiment of this invention. FIG. 4 is a diagram showing a laser beam irradiation spot on a predetermined track of the optical disc in the information recording apparatus of FIG. 3. It is a figure which shows the state which concerns on the modification of this invention and has two spots for preheating. It is a figure which shows the state which concerns on the modification of this invention and the spot for preheating and a part for recording overlap. FIG. 10 is a diagram illustrating a state in which the center of the preheating spot and the recording spot are substantially coincided and the spot diameter of the preheating spot is larger than the spot diameter of the recording spot according to a modification of the present invention. FIG. 10 is a diagram illustrating a state in which a spot shape of a preheating spot is a horizontally long elliptical shape and a spot shape of a recording spot is a vertically long elliptical shape according to a modification of the present invention. It is a figure which shows the state which made the spot shape of the spot for preheating and the spot for recording into a vertically long ellipse shape according to the modification of this invention. It is a figure which shows the state which irradiates the laser beam for preheating with respect to the track | truck of the circumference | surroundings before the track | truck where recording is performed, concerning the modification of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10, 11 ... Information recording apparatus 20, 21 ... Optical system 30 ... Recording beam irradiation means 31 ... 1st laser beam output part 32 ... 1st collimator lens 33 ... Polarizing beam splitter 34 ... 1/4 wavelength plate 35 ... 1st Objective lens 40 ... Preheating beam irradiation means 41 ... Second laser light output part 42 ... Second collimator lens 43 ... Second objective lens 50 ... Light receiving element 60 ... Lens actuator 70 ... Control part (corresponding to control means)
80 ... turntable 81 ... spindle motor 90 ... spectroscope D ... optical disc

Claims (3)

In an information recording apparatus for recording information on a rotating disc,
Preheating beam irradiating means for irradiating the disk with a first laser beam for raising the temperature of the disk within a temperature range lower than a certain threshold value;
A recording beam for irradiating a portion of the disk irradiated with the first laser light with a second laser light for raising the temperature of the disk to a temperature equal to or higher than a certain threshold value. Irradiation means;
Of the preheating beam irradiating means and the recording beam irradiating means, at least control means for controlling the emission of laser light from the recording beam irradiating means;
An information recording apparatus comprising:   The preheating beam irradiating means and the recording beam irradiating means output laser light from the same laser light output unit, and a spectroscope is disposed in the optical path of the laser light. 2. The information recording apparatus according to claim 1, wherein the laser beam is split into the first laser beam and the second laser beam by a spectroscope. In an information recording method for recording information on a rotating disc,
A preheating step for irradiating the disk with a first laser beam for raising the temperature of the disk within a temperature range lower than a certain threshold;
A recording process for raising the temperature of the disk to a temperature equal to or higher than a certain threshold value with respect to a portion irradiated with the first laser beam by the preheating process,
An information recording method comprising:

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