JP2010055726A - Machining device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a machining device which forms a pattern at high speed on a workpiece including a heat mode recording material layer. <P>SOLUTION: Pits P are formed on a recording material layer 33B by radiating laser beams to the workpiece 33 from a plurality of radiation heads 9 provided on the optical pickup 10, so that the recording speed can be made higher than when forming pits P by using only a single radiation head 9. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a processing apparatus, and more particularly to a processing apparatus for processing a member to be processed having a heat mode type recording material layer.

2. Description of the Related Art Conventionally, there is known a processing apparatus that irradiates a processing target with laser light and forms a predetermined pattern on the processing target.
Examples of such a processing apparatus include a method of processing by driving two orthogonal sliders to move a processing object placed on an XY table in the X direction and the Y direction, and a rotating body and an optical system. There is known a method of performing laser processing while rotating an object to be processed by a rotating body in combination. Among these, for the purpose of high-precision processing, the method of performing laser processing while rotating the workpiece, and adjusting the light intensity distribution of the beam spot of the laser beam, the diameter of the beam spot on the workpiece. A method for forming the following fine pattern, a technique for forming a fine pattern corresponding to a concavo-convex pattern to be formed by irradiating a recording laser beam, and the like are disclosed (for example, see Patent Document 1 and Patent Document 2). )

The processing object on which such a fine pattern is formed has been developed into various objects, and a heat mode type recording material layer may be selected for forming the fine pattern. This heat mode type recording material layer is a layer in which a desired pattern is formed by causing a physical or chemical change by photothermal conversion by irradiation, and the generated heat is dissipated when the irradiation speed becomes slow. In addition, it has low illuminance failure characteristics that require more irradiation energy (characteristic that the sensitivity of the photosensitive material decreases as the illuminance is lower and the irradiation time is longer). Therefore, when a pattern is formed (recorded) by irradiation on the heat mode type recording material layer, it is desired to form the pattern at high speed by short-time irradiation.
JP 2007-216263 A WO2004 / 047096

  The present invention has been made for the purpose of solving the above-described conventional problems, and the present invention provides a processing apparatus capable of performing pattern irradiation at high speed on a processing target member having a heat mode type recording material layer. The purpose is to provide.

The above object is achieved by the present invention described below.
That is,
<1> Rotating means for rotating a member to be processed having a heat mode type recording material layer in which information is recorded by heat generated by irradiation of at least a recording laser beam;
A plurality of irradiations that irradiate recording laser beams onto regions that are arranged on a straight line passing through the rotation center of the processing target member rotated by the rotating means and that have different radial distances from the rotation center of the processing target member. Means,
Is a processing apparatus.

<2> The plurality of irradiation means are arranged at predetermined intervals, and the predetermined intervals are from one end portion in the radial direction centered on the rotation center in the predetermined processing target region of the processing target member to the other end portion. Is a value obtained by dividing the distance by the number of the irradiation means.

<3> When a formation pattern corresponding to a predetermined formation target pattern is formed on each of the plurality of irradiation units on the processing target member rotated by the rotation unit, the plurality of irradiation units The above-mentioned control means for controlling the irradiation time and the irradiation intensity of the recording laser light emitted from each of the plurality of irradiation means so that the size and shape of the formation pattern formed by each of them are the same. It is a processing apparatus as described in <1> or said <2>.

<4> A plurality of irradiation waveform generating means provided corresponding to each of the plurality of irradiation means and generating an irradiation waveform;
A plurality of synchronization signal generating means provided corresponding to each of the plurality of irradiation means and generating a synchronization signal;
With
The plurality of irradiation means are synchronized with the synchronization signal input from the corresponding synchronization signal generation means, and the recording laser light of intensity and irradiation time according to the irradiation waveform input from the corresponding irradiation waveform generation means Irradiate
The control means predetermines a synchronization signal to be output to the reference irradiation means as one of the plurality of irradiation means as a reference irradiation means, and outputs the reference synchronization signal to the reference irradiation means. The synchronizing signal generating means is controlled at the same time, and the frequency of the synchronizing signal increases as the distance increases toward the outer peripheral side according to the distance from the reference irradiation means, and the synchronizing signal increases as the distance increases toward the inner peripheral side. By controlling the synchronization signal generating means so that the frequency of the signal is lowered, the irradiation time of the recording laser light emitted from each of the plurality of irradiation means is controlled for each irradiation means. The processing apparatus according to <3>.

<5> An irradiation intensity adjusting means for adjusting a ratio of the maximum irradiation intensity to the minimum irradiation intensity indicated by the irradiation waveform,
The control means defines one of the plurality of irradiation means as a reference irradiation means, and the minimum irradiation intensity indicated by the irradiation waveform as the distance increases toward the outer peripheral side according to the distance from the reference irradiation means. The irradiation intensity adjusting means is controlled so that the ratio of the maximum irradiation intensity with respect to the minimum irradiation intensity indicated by the irradiation waveform increases as the ratio of the maximum irradiation intensity with respect to decreases and the distance increases toward the inner periphery. Thus, the processing apparatus according to <4>, wherein the irradiation intensity of the recording laser beam is controlled for each irradiation unit.

<6> A moving unit that relatively moves the plurality of irradiation units from the inner peripheral side of the processing target member toward the outer peripheral side or from the outer peripheral side of the processing target member toward the inner peripheral side. ,
The irradiation means includes
A light source that emits laser light;
Branching means for branching the laser beam emitted from the light source into at least the recording laser beam and a detection laser beam for detecting a reflectance on the processing target member;
Detecting means for detecting a change in the amount of reflected light from the processing target member of the laser beam for detection;
With
The control means is configured to move the plurality of irradiation means to an area where the recording area is not detected when a recorded area is detected on the processing target member based on a detection result by the detection means. It is a processing apparatus as described in any one of said <1>-<5> characterized by controlling a moving means.

<7> Condensing means for condensing the recording laser light branched by the branching means and the detection laser light so as to be irradiated at a predetermined interval in the radial direction of the workpiece. The processing apparatus according to <6>, further comprising:

<8> The above <6>, wherein the branching unit branches the laser beam emitted from the light source into at least one or more laser beams and at least one or more detection laser beams. It is a processing apparatus as described in said <7>.

  According to the processing apparatus of the present invention, there is provided a processing apparatus capable of writing an irradiation pattern including a pattern equal to or smaller than the laser spot diameter on a processing target member having a heat mode type recording material layer.

(First embodiment)
The processing apparatus 90 (see FIG. 3) of the present embodiment forms pits P as a pattern on the processing target 33 by irradiating the recording target 33 with a recording laser beam.

  The workpiece 33 is in the form of a single disk (disc), and has a configuration in which a recording material layer 33B is laminated on a substrate 33A as shown in FIG. In the present embodiment, the case where the processing object 33 has a configuration in which the recording material layer 33B is stacked on the substrate 33A will be described. However, the processing object used in the processing apparatus 90 of the present embodiment is described. The material 33 may be configured to have at least a recording material layer 33B, which will be described in detail later, and may be configured only by the recording material layer 33B. In addition, the recording material layer 33B may include other layers. Further, a stacked structure may be used.

  The recording material layer 33B is a layer in which the pits P (see FIG. 2) are formed by being deformed by heat generation due to light absorption of the constituent material, and the photothermal energy in the region irradiated by the recording laser light irradiation. This layer is recorded by changing physical properties due to conversion. The pit P is a recess formed in the recording material layer 33B.

  That is, the recording material layer 33B is a layer in which light is converted into heat by irradiation of intense light, and the shape of the material is changed by this heat to form a recess (pit P), which is a so-called heat mode type. It is a layer of recording material. Conventionally, such recording materials have been widely used in recording layers such as optical recording disks. Used.

The recording material layer 33B in the present embodiment is preferably a dye type containing a dye as a recording substance.
Accordingly, the recording material contained in the recording material layer 33B includes organic compounds such as dyes. The material of the recording material layer 33B is not limited to an organic material, and an inorganic material or a composite material of an inorganic material and an organic material is used. However, since an organic material can be easily formed by spin coating and it is difficult to obtain a material having a low transition temperature, it is preferable to use an organic material. Among organic materials, it is preferable to employ a dye whose light absorption can be controlled by molecular design.

  Here, suitable examples of the recording material layer 33B include methine dyes (cyanine dye, hemicyanine dye, styryl dye, oxonol dye, merocyanine dye, etc.), macrocyclic dyes (phthalocyanine dye, naphthalocyanine dye, porphyrin dye, etc.), Examples include azo dyes (including azo metal chelate dyes), arylidene dyes, complex dyes, coumarin dyes, azole derivatives, triazine derivatives, 1-aminobutadiene derivatives, cinnamic acid derivatives, and quinophthalone dyes.

  Among these, the dye-type recording material layer 33B that can record information only once with a laser beam is preferable. This is because an organic recording material is excellent in productivity because it can be dissolved in a solvent and a film can be formed by spin coating or spray coating. The dye-type recording material layer 33B preferably contains a dye having absorption in the recording wavelength region. In particular, the upper limit of the extinction coefficient k indicating the amount of light absorption is preferably 10 or less, more preferably 5 or less, further preferably 3 or less, and 1 or less. Most preferred. The reason is that if the extinction coefficient k is too high, light does not reach from the light incident side to the opposite side of the recording material layer 33B, and non-uniform pits P are formed. Further, the lower limit value of the extinction coefficient k is preferably 0.0001 or more, more preferably 0.001 or more, and further preferably 0.1 or more. The reason is that if the extinction coefficient k is too low, the amount of light absorption is reduced, so that a larger laser power is required and the processing speed may be reduced.

The recording material layer 33B needs to have light absorption at the recording wavelength as described above. From such a viewpoint, the recording material layer 33B corresponds to a light source that emits laser light (corresponding to a laser diode 53 described later (see FIG. 6). )) Can be selected as appropriate according to the wavelength, or the structure can be modified.
For example, when the oscillation wavelength of the laser light source is around 780 nm, it is advantageous to select from pentamethine cyanine dye, heptamethine oxonol dye, pentamethine oxonol dye, phthalocyanine dye, naphthalocyanine dye, and the like.

  When the oscillation wavelength of the light source is around 660 nm, it is advantageous to select from trimethine cyanine dye, pentamethine oxonol dye, azo dye, azo metal complex dye, pyromethene complex dye, and the like.

  Further, when the oscillation wavelength of the light source is around 405 nm, monomethine cyanine dye, monomethine oxonol dye, zero methine merocyanine dye, phthalocyanine dye, azo dye, azo metal complex dye, porphyrin dye, arylidene dye, complex It is advantageous to select from dyes, coumarin dyes, azole derivatives, triazine derivatives, benzotriazole baths, 1-aminobutadiene derivatives, quinophthalone dyes, and the like.

Hereinafter, examples of preferable compounds as the recording material layer 33B are given for the case where the oscillation wavelength of the light source is around 780 nm, around 660 nm, and around 405 nm. Here, compounds (I-1 to I-10) represented by the following chemical formulas 1 and 2 are compounds when the oscillation wavelength of the light source is around 780 nm.
Moreover, the compounds (II-1 to II-8) represented by the chemical formulas 3 and 4 are compounds in the case of around 660 nm. Furthermore, the compounds (III-1 to III-14) represented by 5 and 6 are compounds in the case of around 405 nm. The present embodiment is not limited to the case where these are used for the recording material layer 33B.

  Examples of compounds constituting the recording material layer 33B when the oscillation wavelength of the light source is around 780 nm are shown below.

  Examples of compounds constituting the recording material layer 33B when the oscillation wavelength of the light source is around 660 nm are shown below.

  Examples of compounds constituting the recording material layer 33B when the oscillation wavelength of the light source is around 405 nm are shown below.

  JP-A-4-74690, JP-A-8-127174, 11-53758, 11-334204, 11-334205, 11-334206, 11-334207 The dyes described in JP-A No. 2000-43423, JP-A No. 2000-108513, JP-A No. 2000-158818, and the like are also preferably used.

  In such a dye-type recording material layer 33B, a dye is dissolved in a suitable solvent together with a binder or the like to prepare a coating solution, and then this coating solution is applied onto the substrate 33A to form a coating film. Then, it is formed by drying. In that case, it is preferable that the temperature of the surface which apply | coats a coating liquid is the range of 10 to 40 degreeC. More preferably, the lower limit is 15 ° C. or more, and the upper limit is more preferably 35 ° C. or less, still more preferably 30 ° C. or less, and particularly preferably 27 ° C. or less. Thus, when the surface temperature to be applied is within the above range, the occurrence of coating unevenness and coating failure is prevented, and the thickness of the coating film is adjusted uniformly.

In addition, what is necessary is just to combine each said upper limit value and lower limit value arbitrarily. Here, the recording material layer 33B may be a single layer or a multilayer. In the case of a multilayer structure, the recording material layer 33B is formed by performing a plurality of coating steps.
The concentration of the pigment in the coating solution is generally in the range of 0.01% by mass to 15% by mass, preferably in the range of 0.1% by mass to 10% by mass, more preferably 0.5% by mass. The range is 5% by mass or less, and most preferably 0.5% by mass or more and 3% by mass or less.

  Examples of the solvent for the coating solution include esters such as butyl acetate, ethyl lactate, and cellosolve acetate; ketones such as methyl ethyl ketone, cyclohexanone, and methyl isobutyl ketone; chlorinated hydrocarbons such as dichloromethane, 1,2-dichloroethane, and chloroform; dimethyl ethyl formamide Amides such as methylcyclohexane; amides such as dimethylformamide; hydrocarbons such as methylcyclohexane; ethers such as tetrahydrofuran, ethyl ether, dioxane; ethanol, n-propanol, isopropanol, n-butanol diacetone alcohol, etc. Alcohols; fluorine-based solvents such as 2,2,3,3-tetrafluoropropanol; ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, pro Glycol ethers such as glycol monomethyl ether; and the like.

  The said solvent can be used individually or in combination of 2 or more type in consideration of the solubility of the pigment | dye to be used. In the coating solution, various additives such as an antioxidant, a UV absorber, a plasticizer, and a lubricant may be added according to the purpose.

  Examples of the coating method include a spray method, a spin coating method, a dip method, a roll coating method, a blade coating method, a doctor roll method, a doctor blade method, and a screen printing method. In addition, it is preferable to employ the spin coating method in terms of excellent productivity and easy control of the film thickness.

The recording material layer 33B is preferably dissolved in an amount of 0.3% by mass or more and 30% by mass or less with respect to the organic solvent from the viewpoint that it is advantageous for formation by a spin coating method. More preferably, it dissolves. In particular, it is preferable to dissolve in 1 to 20% by mass in tetrafluoropropanol. Further, the compound constituting the recording material layer 33B preferably has a thermal decomposition temperature of 150 ° C. or higher and 500 ° C. or lower, and more preferably 200 ° C. or higher and 400 ° C. or lower.
During coating, the temperature of the coating solution is preferably in the range of 23 ° C. or more and 50 ° C. or less, more preferably in the range of 24 ° C. or more and 40 ° C. or less, and in particular, in the range of 25 ° C. or more and 30 ° C. or less. It is particularly preferred.

  When the coating solution contains a binder, examples of the binder include natural organic polymer materials such as gelatin, cellulose derivatives, dextran, rosin, and rubber; hydrocarbon resins such as polyethylene, polypropylene, polystyrene, and polyisobutylene; Vinyl resins such as polyvinyl chloride, polyvinylidene chloride, polyvinyl chloride / polyvinyl acetate copolymers, acrylic resins such as polymethyl acrylate and polymethyl methacrylate, polyvinyl alcohol, chlorinated polyethylene, epoxy resin, butyral resin Synthetic organic polymers such as rubber derivatives, precondensates of thermosetting resins such as phenol / formaldehyde resins.

  When a binder is used in combination as the material for the recording material layer 33B, the amount of binder used is generally in the range of 0.01 to 50 times (mass ratio) with respect to the dye, preferably It is in the range of 0.1 to 5 times (mass ratio), and preferably in the range of 0.1 to 5 times (mass ratio).

The recording material layer 33B may contain various browning inhibitors in order to improve the light resistance of the recording material layer 33B.
As a brown inhibitor, a singlet oxygen quencher is generally used regularly. As this singlet oxygen quencher, those already described in publications such as patent specifications of the process are used.

  The solvent application method in the case where the recording material layer 33B is a dye-type recording layer has been described above. However, the recording material layer 33B is formed by a film forming method such as vapor deposition, sputtering, or CVD in accordance with the physical properties of the recording substance. You can also.

  In addition, the pigment | dye with a high absorption factor of another wavelength is employ | adopted in the wavelength of the laser beam used for the process of the pit P mentioned later. The wavelength of the absorption peak of the dye is not necessarily limited to that in the visible light wavelength region, and may be in the ultraviolet region or in the infrared region.

The wavelength λw of the laser light for forming the pits P may be any wavelength that provides a laser power that is large enough to form the pits P due to the shape change by the heat mode. For example, a dye is applied to the recording material layer 33B. When used, it is preferably 1000 nm or less, such as 193 nm, 210 nm, 266 nm, 365 nm, 405 nm, 488 nm, 532 nm, 633 nm, 650 nm, 680 nm, 780 nm, and 830 nm.
In the present embodiment, laser light having an irradiation intensity and wavelength that can form pits P among laser light emitted from a light source (a laser diode 53 described later) will be referred to as recording laser light.

  Further, the type of laser light, that is, the type of laser light emitted from each laser diode 53 to be described later may be any laser such as a gas laser, a solid-state laser, or a semiconductor laser, but freely emits light. It is preferable to employ a laser beam whose interval can be changed. For example, it is preferable to employ a semiconductor laser.

  Further, it is preferable that the laser power (irradiation intensity) of the recording laser light is high in order to increase the processing speed. However, as the laser power is increased, the speed at which the recording material layer 33B is scanned with the recording laser light, for example, the rotational speed of the workpiece 33 must be increased. Therefore, the upper limit value of the laser power is preferably 100 W in consideration of the upper limit value of the rotation speed, more preferably 10 W, still more preferably 5 W, and most preferably 1 W. The lower limit of the laser power is preferably 0.1 mW, more preferably 0.5 mW, and even more preferably 1 mW.

  The thickness of the recording material layer 33B preferably corresponds to the depth of pits P described later. As this thickness, it sets suitably in the range of 1 nm or more and 10,000 nm or less, for example, The minimum of thickness becomes like this. Preferably it is 10 nm or more, More preferably, it is 30 nm or more. The reason is that if the thickness is too thin, the pits P are formed shallow, so that it is difficult to obtain an optical effect. Further, the upper limit of the thickness is preferably 1000 nm or less, and more preferably 500 nm or less. The reason is that if the thickness is too large, a large laser power is required, and it becomes difficult to form the pits P as deep concave portions, and further, the processing speed is reduced.

  The thickness t of the recording material layer 33B and the diameter d of the pits P are preferably in the following relationship. That is, the upper limit of the thickness t of the recording material layer 33B is preferably a value satisfying t <10d, more preferably a value satisfying t <5d, and a value satisfying t <3d. Further preferred. The lower limit value of the thickness t of the recording material layer 33B is preferably a value that satisfies t> d / 100, more preferably a value that satisfies t> d / 10, and t> d / 5. It is more preferable to satisfy the value. The reason why the upper limit value and the lower limit value of the thickness t of the recording material layer 33B are set in this manner in relation to the diameter d of the pit P is the same as described above.

  When the recording material layer 33B is formed, a substance to be a recording material is dissolved or dispersed in an appropriate solvent to prepare a coating solution, and then the coating solution is spin coated, dip coated, exposed coating coated, etc. It is formed by coating on the substrate 33A by a coating method.

Next, the principle that the pits P are formed in the recording material layer 33B will be described.
As shown in FIG. 2, the recording material layer 33B is irradiated with a recording laser beam having a wavelength at which the material constituting the recording material layer 33B absorbs light (wavelength absorbed by the material constituting the recording material layer 33B). Then, the recording laser beam is absorbed by the recording material layer 33B, and the absorbed light is converted into heat, so that the temperature of the irradiated region increases. Thereby, the recording material layer 33B causes one or both of chemical change and physical change such as softening, liquefaction, vaporization, sublimation, and decomposition. And the pit P is formed because the material which caused such a change becomes one or both of movement and disappearance.

  Note that it is preferable that the recording material layer 33B as described above vaporizes, sublimates, or decomposes at a high rate of change. Specifically, the weight reduction rate by differential thermal balance (TG-DTA) during vaporization, sublimation, or decomposition of the material constituting the recording material layer 33B is preferably 5% or more, more preferably 10% or more. More preferably, it is 20% or more. Further, the slope of weight reduction (weight reduction rate per 1 ° C. temperature increase) by a differential thermal balance (TG-DTA) during vaporization, sublimation, or decomposition of the material constituting the recording material layer 33B is 0.1% / ° C. or more. Preferably, it is 0.2% / ° C. or more, more preferably 0.4% / ° C. or more.

  Further, the upper limit of the transition temperature of at least one of chemical change and physical change such as softening, liquefaction, vaporization, sublimation, and decomposition is preferably 2000 ° C. or less, more preferably 1000 ° C. or less, and 500 More preferably, it is not higher than ° C. The reason is that if the transition temperature is too high, a large laser power is required. The lower limit of the transition temperature is preferably 50 ° C. or higher, more preferably 100 ° C. or higher, and further preferably 150 ° C. or higher. The reason is that if the transition temperature is too low, there is little temperature gradient with respect to the surroundings, making it difficult to form pits P having a clear shape.

  Next, the processing apparatus 90 of this Embodiment is demonstrated.

  The processing apparatus 90 according to the present embodiment forms pits P in the processing target 33 by irradiating the processing target 33 provided with the above-described recording material layer 33B with a recording laser beam.

  The processing apparatus 90 according to the present embodiment includes an optical pickup 10, a spindle motor 11, an amplifier 12, a servo circuit 13, a decoder 15, a control unit 16, and a strategy circuit 18 (strategy circuit 18A and strategy circuit 18B). A laser driver 19 (laser driver 19A, laser driver 19B), a laser power control circuit 20 (laser power control circuit 20A, laser power control circuit 20B), a frequency generator 21, a stepping motor 30, and a motor driver 31. A motor controller 32, a memory 36, and a pulse generator 35.

  In the present embodiment, when the parts of the apparatus having the same function are collectively described, the description is omitted. For example, as the strategy circuit, the processing apparatus 90 of the present embodiment is provided with two strategy circuits 18A and 18B. However, when these are described generically, they are referred to as the strategy circuit 18. I will explain. The same shall apply hereinafter.

  The spindle motor 11 is a motor that rotationally drives the workpiece 33, and the rotation speed is controlled by the servo circuit 13. In the processing apparatus 90 according to the present embodiment, a method of driving the processing object 33 at a constant angular velocity (CAV: Constant Angular Velocity), or a method of rotating the processing object 33 so as to have a constant recording linear velocity (CLV: It is assumed that the recording is performed by Constant Linear Velocity). For this reason, the spindle motor 11 is rotated at a constant angular velocity or a constant linear velocity set by an instruction from the control unit 16 or the like.

  The optical pickup 10 is a device for irradiating a recording laser beam onto a workpiece 33 that is rotated by the spindle motor 11, and can irradiate a recording laser beam on different regions on the workpiece 33. As shown, the plurality of irradiation heads 9 are included. In the present embodiment, this different area means that the radial position (the shortest distance from the rotation center Q) when the rotation center Q of the workpiece 33 is the center is different. For this reason, the plurality of irradiation heads 9 provided in the optical pickup 10 are configured to irradiate recording laser beams onto regions having different radii around the rotation center Q of the workpiece 33.

  In this embodiment, in order to simplify the description, it is assumed that two irradiation heads, that is, the irradiation head 9A and the irradiation head 9B, are provided as the plurality of irradiation heads. A configuration in which (two or more) irradiation heads 9 are provided is sufficient, and a configuration in which three or more irradiation heads 9 are provided may be employed.

  As shown in FIG. 4, these irradiation head 9 </ b> A and irradiation head 9 </ b> B are formed on the workpiece 33 that is rotated in a predetermined direction (in the direction of arrow X in FIG. 4) about the rotation center Q by the spindle motor 11. On a straight line passing through the rotation center Q, they are arranged at a predetermined interval. Each of the plurality of irradiation heads 9 </ b> A and 9 </ b> B is fixed to the support member 17 extended in the radial direction of the workpiece 33 with the predetermined interval. The support member 17 is connected to a stepping motor 30 to be described later, and the irradiation supported by the support member 17 when the stepping motor 30 is driven through the motor controller 32 and the motor driver 31 under the control of the control unit 16. The workpiece 33 is configured to be movable in the radial direction while the head 9A and the irradiation head 9B maintain the predetermined interval.

  For this reason, while the recording laser beam is irradiated onto the workpiece 33 by each irradiation head 9 of the optical pickup 10, the optical pickup 10 is moved in the radial direction by driving the stepping motor 30. Pits P are formed over the entire surface of a predetermined processing target area 33P in the entire area 33.

  In the present embodiment, the irradiation head 9A and the irradiation head 9B as the plurality of irradiation heads 9 provided in the optical pickup 10 are one end in the radial direction in a predetermined processing target region 33P of the processing target 33. Although the case where it is provided in a part of area | region from a part to an other end part is demonstrated, the several irradiation head 9 is arranged at predetermined intervals over the whole area | region from this one end part to an other end part. It may be a configuration.

  The distance between the plurality of irradiation heads 9 is obtained by dividing the distance from one end to the other end in the radial direction in the processing target area 33P of the processing target 33 by the number of irradiation heads 9 provided in the optical pickup 10. This distance is preferable because the time required for processing per sheet is the shortest.

  As shown in FIG. 6, each irradiation head 9 (irradiation head 9 </ b> A and irradiation head 9 </ b> B) records a laser diode 53 that emits a recording laser beam B and a recording laser beam B on a workpiece 33. An optical system 55 that focuses light onto the material layer 33B and a light receiving element 56 that receives reflected light are provided. Since the configuration of each of these irradiation heads 9 is the same as each other, they will be described together.

  In each irradiation head 9, the laser diode 53 changes according to the irradiation waveform from a laser driver 19 (see FIG. 3 laser driver 19A and laser driver 19B), which will be described later in detail, corresponding to each irradiation head 9. By supplying the voltage to be synchronized with the clock signal, the recording laser beam B having the intensity corresponding to the voltage that changes according to the irradiation waveform is emitted. In the optical pickup 10, the recording laser beam B emitted from the laser diode 53 passes through the polarization beam splitter 59, the collimator lens 60, the ¼ wavelength plate 61, and the objective lens 62, and is applied to the recording material layer 33 </ b> B of the workpiece 33. Collect light. Then, the laser light reflected by the recording material layer 33B is transmitted again through the objective lens 62, the quarter wavelength plate 61, and the collimator lens 60, reflected by the polarization beam splitter 59, passed through the cylindrical lens 63, and then received by the light receiving element. 56 so as to be incident. The light receiving element 56 outputs a received signal to the amplifier 12 (see FIG. 3), and the received light signal is supplied to the control unit 16 and the servo circuit 13 via the amplifier 12.

  The objective lens 62 is held by a focus actuator 64 and a tracking actuator 65 and can move in the optical axis direction of the laser light B and the radial direction of the light of the workpiece 33. Each of the focus actuator 64 and the tracking actuator 65 moves the objective lens 62 in the optical axis direction and the radial direction according to the focus error signal and the tracking error signal supplied from the servo circuit 13 (see FIG. 3). The servo circuit 13 generates a focus error signal and a tracking error signal based on the light reception signal supplied via the light receiving element 56 and the amplifier 12, and moves the objective lens 62 as described above to perform focus control and Perform tracking control.

  The servo circuit 13 is supplied with an instruction signal from the control unit 16, an FG pulse signal having a frequency corresponding to the rotation speed of the spindle motor 11 supplied from the frequency generator 21, and a signal from the amplifier 12. The servo circuit 13 performs rotation control of the spindle motor 11 and focus control and tracking control of the optical pickup 10 based on these supplied signals. As a driving method of the spindle motor 11 when information is recorded on the recording material layer 33B of the processing object 33 (pit P is formed), as described above, the processing object 33 is driven at a constant angular velocity (CAV). ) And a method (CLV) of rotating the workpiece 33 so as to obtain a constant recording linear velocity may be used.

  The memory 36 stores recording data including pit information to be recorded on the workpiece 33 in advance. Then, the recording data stored in the memory 36 is output to the control unit 16. The recording data is input, for example, from the PC 38 by connecting the control unit 16 to a PC (personal computer) 38 or the like in advance so that signals can be transmitted and received, and the input recording data is stored in the memory 36 in advance. do it.

Although the details will be described later, the control unit 16 determines the position and shape of the pits P to be recorded on the recording material layer 33B of the processing target 33 included in the recording data based on the recording data read from the memory 36. For each pit P, irradiation waveform information indicating the irradiation waveform output to each irradiation head 9 and information indicating irradiation intensity information indicating the irradiation intensity are generated as pit P formation information. Then, the generated pit formation information is rearranged so that the generated information is arranged in order from the innermost side to the outermost side of the region to be recorded by each irradiation head 9.
Of the information indicating the rearranged pits P, the irradiation waveform information is output to the strategy circuit 18 connected to the corresponding irradiation head 9, and the irradiation intensity information indicating the irradiation intensity is the corresponding irradiation head 9. Is output to the laser power control circuit 20 connected to (details will be described later).

  Further, in the control unit 16, clock frequency information indicating the frequency of a synchronization signal (so-called clock signal) used for timing adjustment and irradiation time adjustment when each irradiation head 9 irradiates laser light is provided for each irradiation head 9. To create. The generated clock frequency information is output to the pulse generator 35 together with information indicating the corresponding irradiation head 9. The pulse generator 35 generates a clock signal having the frequency of the input clock frequency information for each irradiation head 9 and outputs the generated clock signal to the driver 19 connected to the corresponding irradiation head 9.

  This clock frequency information is the length of the pit P formed when the recording material layer 33B of the rotating workpiece 33 is irradiated with laser light for a period of N clocks (N is an integer of 1 or more). However, even if any of the plurality of irradiation heads 9 is formed in different regions of the radial position of the recording material layer 33B of the processing target 33, the same length and shape are obtained. The calculation is performed according to the distance from the rotation center Q of each irradiation head 9 such that the clock frequency is higher (the clock cycle is shorter) as the irradiation head 9 is provided on the outermost peripheral side.

A specific calculation method of the clock frequency information generated for each irradiation head 9 in the control unit 16 will be described in more detail.
When the workpiece 33 is recorded (rotated) by the CLV method with a constant linear velocity, even if the optical pickup 10 is moved from the inner circumference side to the outer circumference side or from the outer circumference side to the inner circumference side by the stepping motor 30. The speed of the workpiece 33 in the region irradiated with the laser beam by each of the plurality of irradiation heads 9 is constant. For this reason, when the linear velocity is constant, one of the plurality of irradiation heads 9 (for example, the irradiation head 9A disposed on the innermost peripheral side) is determined as a reference irradiation head and is used as the reference. In accordance with the radial distance from the irradiation head 9A, the optical pickup 10 is provided on the downstream side in the moving direction of the optical pickup 10 (the outer peripheral side when the optical pickup 10 moves from the inner peripheral side to the outer peripheral side). The clock frequency is calculated for each irradiation head 9 so that the irradiation head 9 has a higher clock frequency and the irradiation head 9 provided upstream in the movement direction has a lower clock frequency.

For example, as shown in FIG. 5, three irradiation heads 9 </ b> A, irradiation heads 9 </ b> B, and irradiation heads 9 </ b> C are arranged in the optical pickup 10 as a plurality of irradiation heads 9 in the radial direction from the inner peripheral side to the outer peripheral side of the workpiece 33. Are arranged so as to be arranged at predetermined intervals. Further, it is assumed that the distances from the respective rotation centers Q of the irradiation heads 9A, 9B, and 9C when the optical pickup 10 is at the reference position are R1, R2, and R3, respectively. Assume that the reference clock frequency of the clock signal generated by a crystal oscillator (not shown) is F1. The optical pickup 10 is moved from the inner peripheral side toward the outer peripheral side. In this case, when recording is performed at a constant linear velocity, for example, as shown in FIG. 8A, the irradiation head 9A arranged on the innermost peripheral side of the plurality of irradiation heads 9 is determined as the reference irradiation head. . A frequency F1 (clock signal period 1 / F1) is determined as the frequency of the clock signal T1 of the irradiation head 9A. As shown in FIG. 8B, the frequency F2 of the clock signal T2 of the irradiation head 9B arranged adjacent to the outer peripheral side of the irradiation head 9A is calculated by (R2 / R1) / F1. Determine. The cycle of the clock signal T2 at this time is (1 / F1) × (R1 / R2).
Further, similarly, the calculation result by (R3 / R1) / F1 is determined as the frequency F3 of the clock signal T3 of the irradiation head 9C arranged adjacent to the outer peripheral side of the irradiation head 9B. The period of the clock signal T2 at this time is (1 / F1) × (R1 / R3).

  As described above, when the linear velocity is constant, among the plurality of irradiation heads 9 provided in the optical pickup 10, for example, one irradiation head 9A disposed on the innermost peripheral side as the reference irradiation head 9 Is used as a reference to determine the clock frequency F1. The clock frequency of each of the other one or a plurality of irradiation heads 9 arranged from the irradiation head 9A toward the outer peripheral side is irradiated when the radius from the rotation center Q of each irradiation head 9 is Rn. It is obtained from an equation of clock frequency F1 × (Rn / R1) of the head 9A (see FIG. 8C).

  Note that n represents an integer, and when the irradiation head 9A arranged on the innermost peripheral side is the irradiation head positioned “1”, the irradiation head 9 positioned first. The values are shown when sequential numbers are assigned in order for each of the irradiation heads 9 arranged toward the outer peripheral side. For this reason, the radius from the rotation center Q of the irradiation head 9A disposed on the innermost periphery is denoted as R1.

  As described above, as the clock frequency F1 of the irradiation head 9A, the frequency of the clock signal having a frequency corresponding to the rotation speed of the workpiece 33 generated by a crystal oscillator (not shown) is determined as the reference clock frequency. Just do it.

  When the workpiece 33 is recorded (rotated) by the CLV method with a constant linear velocity as described above, the optical pickup 10 moves from the inner circumference side to the outer circumference side of the workpiece 33, so that each Even if the position of the irradiation head 9 moves to the outer peripheral side while maintaining the mutual interval, the speed of the workpiece 33 in the region irradiated with the laser light by each irradiation head 9 is the same as before the movement. For this reason, in the case of recording by the CLV method, the control unit 16 determines each irradiation head 9 based on the distance from the rotation center Q of each irradiation head 9 when the optical pickup 10 is located at the reference position. After the frequency of the clock signal is calculated, the frequency of the clock signal calculated when the optical pickup 10 is positioned at the reference position is used without calculating the frequency of the clock signal again even when the optical pickup 10 moves to the outer peripheral side. Thus, adjustment is performed so that the entire area of the processing target area 33P of the processing target 33 is recorded by each irradiation head 9.

  On the other hand, when the workpiece 33 is recorded (rotated) by the CAV method having a constant angular velocity, the plurality of irradiation heads 9 are moved according to the movement of the optical pickup 10 from the inner peripheral side to the outer peripheral side by the stepping motor 30. As the distance from each rotation center Q changes, the speed of the workpiece 33 in the region irradiated with the laser beam by each irradiation head 9 changes. For this reason, when recording by the CAV method, the control unit 16 changes according to the change in the distance from the rotation center Q of each irradiation head 9 as the optical pickup 10 moves from the inner periphery side to the outer periphery side. The frequency of the clock signal for each irradiation head 9 may be calculated based on the later distance and output to the pulse generator 35.

  Based on the irradiation waveform information supplied from the strategy circuit 18, the irradiation intensity information supplied from the laser power control circuit 20, and the synchronization signal supplied from the pulse generator 35, the laser driver 19 The diode 53 (see FIG. 6) is driven.

  The pulse generation unit 35 uses a clock signal used as a synchronization signal in each irradiation head 9 of the optical pickup 10 based on the clock frequency information corresponding to each irradiation head 9 input from the control unit 16. Create a clock frequency of

The pulse generator 35 includes a plurality of pulse generators 35 corresponding to the respective irradiation heads 9. As shown in FIGS. 3 and 4, two irradiation heads 9A and a plurality of irradiation heads 9 are provided. When the irradiation head 9 </ b> B is provided, the configuration includes two pulse generation units corresponding to the respective irradiation heads 9. Specifically, the pulse generation unit 35 includes a pulse generation unit 35A corresponding to the irradiation head 9A, and a pulse generation unit 35B corresponding to the irradiation head 9B.
Each of the pulse generator 35A and the pulse generator 35B generates a clock signal having a frequency corresponding to the clock frequency information based on the clock frequency information transmitted from the controller 16, and each corresponding laser driver 19A. And output to the laser driver 19B.

  The laser power control circuit 20 (laser power control circuit 20A and laser power control circuit 20B) is provided corresponding to each of the plurality of irradiation heads 9, and irradiation intensity information indicating the irradiation intensity input from the control unit 16 is provided. The laser intensity of the recording laser light emitted from the corresponding irradiation head 9 is adjusted so that the recording laser light of the intensity is irradiated.

  The stepping motor 30 is a motor for moving the optical pickup 10 in the radial direction of the workpiece 33. When the optical pickup 10 is moved in the radial direction of the workpiece 33 by the stepping motor 30, the plurality of irradiation heads 9 provided in the optical pickup 10 are also moved in the radial direction of the workpiece 33 along with the movement. Moved. In the present embodiment, the processing object 33 is described as moving from the inner peripheral side toward the outer peripheral side, but may be configured to move from the outer peripheral side toward the inner peripheral side.

  The motor driver 31 rotates the stepping motor 30 by an amount corresponding to the pulse signal supplied from the motor controller 32. The motor controller 32 generates a pulse signal according to the movement amount and the movement direction according to the movement start instruction including the movement direction and movement amount in the radial direction of the optical pickup 10 instructed from the control unit 16, and the motor driver 31. Output to. When the stepping motor 30 moves the optical pickup 10 in the radial direction of the workpiece 33 and the spindle motor 11 rotates the workpiece 33 on the workpiece 33, the laser beam irradiation position of the workpiece 33 light. Are moved to various positions on the workpiece 33.

  The control unit 16 includes a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and the like, and controls each unit of the processing device 90 according to a program stored in the ROM. The recording process for the workpiece 33 is centrally controlled.

  Next, a process executed when the pit P is formed on the workpiece 33 in the control unit 16 of the processing apparatus 90 having the above configuration will be described.

  In the control unit 16, when the processing object 33 is set in a slot (not shown) of the processing device 90 and a power switch (not shown) of the processing device 90 is operated to supply power to each unit, The program for executing the processing routine shown in FIG. 7 stored in advance in the ROM in the unit 16 is read, and the process proceeds to Step 200.

  Note that the workpiece 33 is mounted in a slot (not shown) so that recording by each irradiation head 9 provided in the optical pickup 10 is possible.

  In the processing routine shown in FIG. 7 below, a case will be described in which the driving method of the spindle motor 11 mounted on the processing apparatus 90, that is, the recording method of the workpiece 33 is the CLV method with a constant linear velocity.

  The execution of the recording method by the CLV method is performed, for example, from a PC 38 (see FIG. 3) connected to the control unit 16 so as to be able to send and receive signals after power is supplied to each part of the apparatus and before the process of step 200 is executed. It may be executed by reading that the information indicating whether the method is the method of the above, and reading that the input information is the information indicating the CLV method. In addition, an input / output unit such as a keyboard for performing various operations (not shown) is provided in the control unit 16, and the CLV method or the CAV method is input by operating the input / output unit by an operator. The determination may be made by determining the input signal. The input by the operator is, for example, a display screen such as a monitor provided in advance so as to be able to send and receive signals to the control unit 16, and information for selecting which method to record on the display screen is displayed. What is necessary is just to comprise previously so that an operator can perform selection instruction | indication via an input part based on this display information.

  In step 200, the recording data to be recorded on the recording material layer 33 </ b> B of the processing object 33 is read from the memory 36. This recorded data includes, for example, pit P information indicating each pit P formed in the recording material layer 33B of the workpiece 33. The pit P information includes position information indicating the position coordinates of each pit P on the workpiece 33, and information indicating the shape, size, depth, and the like of the pit P.

  In the next step 202, the distance from the rotation center Q on the workpiece 33 of each pit P is read based on the pit P information of each pit P read in step 200. As a method for reading the distance from the rotation center Q, the distance from the rotation center Q may be calculated based on the position information included in each pit P information.

  In the next step 204, the irradiation head 9 to be recorded with each pit P is specified based on the distance from the rotation center Q of each pit P read in step 202.

For example, as shown in FIG. 4, if the optical pickup 10 is provided with two irradiation heads 9 </ b> A and 9 </ b> B, the optical pickup 10 is processed by the stepping motor 30. Since it is provided so as to be movable in the radial direction, from the innermost peripheral side in the processing target region 33P that is a region excluding the non-processing target region around the rotation center Q of the processing target 33, the processing target region 33P A region reaching the central portion in the radial direction is an irradiation target region by the irradiation head 9A provided on the inner peripheral side. And the area | region which reaches the outer periphery from the radial direction center part of 33D of process target areas turns into an irradiation object area | region by the irradiation head 9B provided in the outer peripheral side.
Then, by determining in which area of the irradiation target area each of these irradiation heads 9 the distance from the rotation stop Q of each pit P calculated in step 202 is determined, each pit P What is necessary is just to specify the irradiation head 9 (irradiation head 9A or irradiation head 9B) which forms P.

  In the next step 206, the irradiation waveform and irradiation intensity of the laser irradiated to the workpiece 33 to form each pit P are derived for each pit P from the recording data read in step 200, and the next step 208 is performed. In the memory 36.

  The irradiation intensity information indicating the irradiation intensity indicates the intensity of the recording laser beam to be irradiated in order to form the pits P having a desired length (length in the rotation direction), depth, and shape on the workpiece 33. As shown in FIG. 10, the information includes information indicating the ratio of the peak intensity Pn to the bias intensity Tn in the irradiation waveform described later.

  The irradiation time and irradiation intensity are determined by the irradiation amount (irradiation energy) necessary for forming the pits P to be formed on the recording material layer 33B of the workpiece 33, and each pit included in the recording data is determined. It is adjusted from the information indicating the shape and depth. Assuming that the pits P are formed at the same location with the same irradiation energy, the irradiation intensity may be smaller as the irradiation time is longer, and the irradiation intensity may be adjusted to be higher as the irradiation time is shorter. Therefore, these values may be appropriately determined from the balance between the irradiation time and the irradiation intensity.

  The information indicating the ratio of the peak intensity Pn to the bias intensity Tn in the irradiation waveform as the irradiation intensity information is N clocks (N is 1 or more) with respect to the recording material layer 33B of the workpiece 33 being rotated. The shape and depth of the pits P formed by irradiating the laser beam for a period of (integer) are formed in different regions on the workpiece 33 by any one of the plurality of irradiation heads 9. Even if it is a case, it calculates according to the distance from the rotation center Q of each irradiation head 9 so that it may become the same shape and depth.

  Specifically, when it is assumed that pits P having the same shape and depth are formed, the ratio of the peak intensity Pn to the bias intensity Tn irradiated toward the irradiation head 9 provided on the outer peripheral side becomes small. In this way, the calculation may be performed according to the distance from the rotation center Q of each irradiation head 9.

  For example, the peak intensity Pn is constant, the value of 1 / Fn that is the period of the clock signal derived for each irradiation head 9 is calculated as the value of the bias intensity Tn, and this ratio may be used as irradiation intensity information. . Note that “n” of Fn is an integer indicating the position of each irradiation head 9 as described above, and the irradiation head 9 provided on the innermost peripheral side is set to “1” as an initial value, and the irradiation head For the irradiation heads 9 arranged from 9 to the outer peripheral side, numerical values counted up in order from the inner peripheral side may be determined.

  The irradiation waveform is a waveform indicating a change rate of irradiation intensity when one pit P is formed by irradiating the recording laser beam from each irradiation head 9 to the recording material layer 33B of the workpiece 33. is there. The time from the rise to the fall of the irradiation waveform is determined according to the number of clocks corresponding to the length of the pit P to be formed. For example, when one clock is one cycle in the clock signal, when a pit P having a length of one clock is formed, it corresponds to the irradiation waveform having a pulse width corresponding to the time from the start to the end of the cycle of one clock. The recording laser light whose irradiation intensity changes at a changing rate is irradiated. When a pit having a length of 2 clocks is formed, a recording laser whose irradiation intensity changes at a rate corresponding to the irradiation waveform of the pulse width corresponding to the time from the start to the end of the cycle of 2 clocks. Light is irradiated.

  That is, the recording laser light whose irradiation intensity changes at a change rate according to the irradiation waveform is irradiated onto the workpiece 33, so that the length corresponding to the irradiation time and irradiation intensity of the irradiated recording laser light. A pit P having a shape and a depth is formed.

  The irradiation waveform is actually sent from the driver 19 to the irradiation head 9 in synchronization with the clock signal, so that the time from the rising to the falling of the irradiation waveform is adjusted. Therefore, the irradiation waveform output from the driver 19 to the irradiation head 9 corresponds to each irradiation head 9 input from the pulse generation unit 35 to the irradiation waveform sent from the control unit 16 to the strategy circuit 18 in the driver 19. The waveform is modulated in synchronization with the frequency clock signal. That is, by adjusting the frequency of the clock signal in each irradiation head 9, the irradiation time of the recording laser light irradiated from each irradiation head 9 is adjusted.

  Further, by adjusting the bias intensity and the peak intensity of the irradiation waveform in accordance with the ratio of the peak intensity Pn to the bias intensity Tn as the irradiation intensity information, the recording laser light irradiated from each irradiation head 9 is irradiated. The strength will be adjusted.

  Here, as described above, the recording material layer 33B to be formed by the processing apparatus 90 of the present embodiment forms the pits P by the heat energy generated by the laser light irradiation. Compared to the recording start point (upstream in the rotation direction of the workpiece 33), the pit P formed at the recording end point (downstream in the rotation direction of the workpiece 33) tends to be thicker. It is also known that the distance between the pits P may be close and connected depending on the rotation speed of the workpiece 33 and the intensity of the irradiated laser beam.

  Specifically, assuming that the clock period is T (see FIG. 9B), for example, as an irradiation waveform for forming a pit P having a length of 3 × T (see FIG. 9A), FIG. When the laser beam is irradiated so that the pulse width (length from the rising edge to the falling edge) as shown in (C) has the irradiation amount change indicated by the irradiation waveform having the length of 3T, it is actually formed. The pit P may extend or rub toward the downstream side of the rotation direction of the workpiece 33 (in the direction of arrow X in FIG. 9), or the pit P shape may be different from the target shape.

  In order to prevent such a phenomenon, in the processing apparatus 90 of the present embodiment, the one-pulse type (FIG. 9 (FIG. 9)) is an irradiation waveform indicated by a rectangular pulse having a pulse width less than the length (for example, 3T) of the pit P to be formed. D)), a multi-pulse type (see 10 (E)) that is an irradiation waveform that falls in one clock cycle, an L shape type (see FIG. 9F) that is an L-type irradiation waveform, and a waveform. An irradiation waveform of a castle type (FIG. 9G) constituted by a top pulse, an intermediate bias portion, and a last pulse is appropriately used.

  The irradiation waveform information indicating these irradiation waveforms corresponds to information such as the distance between the pits P to be formed, the rotation speed of the workpiece 33, the irradiation intensity for forming each pit P, and the like in advance in the memory 36. Is remembered. For example, when the distance between the pits P, the rotation speed of the workpiece 33, and the irradiation intensity are specific setting values, the recording laser light is processed from the irradiation head 9 with the setting values. In the pit P recorded when the object 33 is irradiated, the thickness of the pit P as described above is not uniform in the rotation direction X, is connected to the adjacent pits P, or causes a shape change. It is only necessary to obtain an irradiation waveform having no emission in advance by experiment, and to record irradiation waveform information indicating the obtained irradiation waveform in the memory 36 in advance in association with the corresponding set value.

  In the process of step 206, the control unit 16 includes, for example, irradiation intensity information indicating the irradiation intensity of each pit P, rotation speed information indicating the rotation speed of the workpiece 33, and distance information indicating the distance between the pits P. By reading the corresponding irradiation waveform information from the memory 36, as the irradiation waveform information corresponding to each pitch P, information indicating a one-pulse type, information indicating a multi-pulse type, information indicating an L shape type, or information indicating a castle type Can be read.

  By this process, an irradiation waveform for forming an optimum pit P in which rubbing, bleeding, etc. are suppressed is selected for each pit P, and the irradiation waveform is formed by the irradiation head 9 which is a target for forming each pit P. The pits P are formed by irradiating the laser beam according to the above.

  In the next step 210, the frequency of the clock signal generated by a crystal oscillator (not shown) is set as a reference clock frequency and read from the clock signal generated by the crystal oscillator. In the next step 212, the reference clock frequency read in step 210 is determined as the frequency of the clock signal of the irradiation head 9A provided on the innermost periphery among the plurality of irradiation heads 9 of the optical pickup 10, and the irradiation is performed. The reference clock frequency information of the reference clock frequency is stored in the memory 36 in association with information indicating the head 9A.

  In the next step 214, the clock frequency of the clock signal to be used in each of the irradiation heads 9 arranged on the outer peripheral side from the irradiation head 9A arranged on the innermost peripheral side is calculated. In the calculation of the frequency in step 214, as described above, the pit P formed by irradiating the rotating workpiece 33 with laser light for a period of N clocks (N is an integer of 1 or more). Are provided on the outer peripheral side so as to have the same length even when the irradiation heads 9 are formed in different regions on the workpiece 33 by any of the irradiation heads 9. The calculation is made according to the distance from the rotation center Q of each irradiation head 9 so that the clock frequency of the irradiation head 9 is higher (the clock cycle is shorter).

  In the next step 216, the clock frequency information indicating the frequency of the clock signal calculated for each irradiation head 9 in step 214 is stored in the memory 36 in association with the information indicating the corresponding irradiation head 9.

  In the next step 218, a movement start instruction signal indicating that the optical pickup 10 is moved to the reference position is output to the motor controller 32. By outputting the movement start signal to the motor controller 32, the stepping motor 30 is driven via the motor driver 31, and the optical pickup 10 is arranged at the reference position (the innermost peripheral side of the plurality of irradiation heads 9). The irradiation head 9 </ b> A is moved to a state where the irradiation head 9 </ b> A is positioned in the innermost peripheral region in the processing target region 33 </ b> P of the processing target 33.

  In the next step 220, a rotation start instruction signal indicating the start of rotation of the workpiece 33 is output to the servo circuit 13. The servo circuit 13 that has received the rotation start instruction signal controls the rotation of the spindle motor 11, thereby starting the rotation of the workpiece 33. In the processing routine shown in FIG. 7, as described above, a case in which the rotation method (recording method) in the CLV method with a constant linear velocity is used will be described. Therefore, the rotation instruction signal includes information indicating the CLV method. The rotation of the spindle motor 11 based on the information starts rotation with a constant linear velocity by the workpiece 33.

  In the next step 222, irradiation head information indicating each irradiation head 9 provided in the optical pickup 10 and clock frequency information derived corresponding to the irradiation head information are read from the memory 36, and irradiation of each irradiation head information is performed. The data is output to the pulse generator 35A and the pulse generator 35B of the pulse generator 35 corresponding to the head 9.

  In the next step 224, the irradiation head information indicating each irradiation head 9 provided in the optical pickup 10, the irradiation waveform information indicating the irradiation waveform derived corresponding to the irradiation head information, and the irradiation intensity information are stored in the memory 36. Are output to the laser power control circuit 20 (laser power control circuit 20A, laser power control circuit 20B) corresponding to the irradiation head 9 and the strategy circuit 18 (strategy circuit 18A, strategy circuit 18B).

  Specifically, the irradiation waveform information is output to the corresponding strategy circuit 18, and the irradiation waveform information is output to the corresponding strategy circuit 18. The irradiation intensity information is output to the laser power control circuit 20.

  In each of the pulse generation unit 35A and the pulse generation unit 35B provided in accordance with the irradiation head 9 corresponding to the irradiation head 9 by the processing of step 22 and step 224, the clock frequency information Are generated and output to the corresponding laser driver 19A and laser driver 19B.

  Further, in the strategy circuit 18A and the strategy circuit 18B, irradiation waveforms corresponding to the input irradiation waveform information are generated and output to the corresponding laser driver 19A and laser driver 19B, respectively. Further, in the laser power control circuit 20A and the laser power control circuit 20B, the peak intensity information and the bias intensity information included in the input irradiation intensity information are output to the corresponding laser driver 19A and laser driver 19B, respectively. The

  Each of the laser driver 19A and the laser driver 19B to which the irradiation waveform, peak intensity information, and bias intensity information are input is the peak intensity information in which the peak intensity of the irradiation waveform is input based on the peak intensity information and the bias intensity information. After correcting the irradiation waveform so that the bias intensity of the irradiation waveform becomes the bias intensity of the input bias intensity information, the corrected irradiation waveforms thus corrected are respectively applied to the irradiation heads 9A and 9B. Output to each of. This corrected irradiation waveform is one or more arranged in the order of being formed in the rotation direction of the workpiece 33 among the plurality of pits P to be formed in each irradiation head 9, located on the innermost side. Are sequentially output from the pit P to the laser driver 19.

  In the irradiation head 9A and the irradiation head 9B to which the corrected irradiation waveform and the clock signal are input, the recording laser light having the irradiation intensity corresponding to the voltage that changes in accordance with the input correction irradiation waveform is synchronized with the clock signal. Let it irradiate.

  In step 226, the negative determination is repeated until formation of all the pits P included in the recording data read in step 200 is completed. When the determination is affirmative, this routine is ended.

  Although not described above, the irradiation head 9A and the irradiation head 9B, to which the corrected irradiation waveform and the clock signal are input, are input by executing the processing of the above steps 222 and 224, respectively. The recording laser beam having the irradiation intensity corresponding to the voltage changing according to the corrected irradiation waveform is irradiated in synchronization with the clock signal, so that the pits P are sequentially formed on the workpiece 33 from the inner periphery side to the outer periphery side. At this time, each time the pit P recording for one round is completed by each of the irradiation heads 9, the stepping motor is controlled by the control unit 16 via the motor controller 32 and the motor driver 31. 30 is controlled, and the optical pickup 10 is moved from the inner peripheral side in the radial direction of the workpiece 33 toward the outer peripheral side.

  In this way, the pits P are formed in the entire region of the processing target region 33P of the processing target 33.

  As described above, in the processing apparatus 90 of the present embodiment, the laser beam is emitted by each of the plurality of irradiation heads 9 provided in the optical pickup 10 by executing the processing of the above-described steps 200 to 226. Since the pit P is formed in the recording material layer 33B by irradiating the workpiece 33, the recording speed can be further increased as compared with the case where the pit P is formed by only one irradiation head 9.

The length of the pits P formed by irradiating the recording material layer 33B of the rotating workpiece 33 with laser light for a predetermined clock period is any of the plurality of irradiation heads 9. Even when the irradiation head 9 is formed in different regions of the recording material layer 33B of the workpiece 33, each of the plurality of irradiation heads 9 is individually controlled so as to have the same length.
Specifically, for each irradiation head 9 according to the distance from the rotation center Q of each irradiation head 9, the clock frequency is higher (the clock cycle is shorter) as the irradiation head 9 is provided on the outer peripheral side. Since the frequency of the clock signal is calculated and the laser light is emitted from each irradiation head 9 in synchronization with the clock signal, the irradiation time of the laser light emitted from each irradiation head 9 can be easily set with a simple configuration. It is adjusted for each irradiation head 9. For this reason, the pits P are formed in the entire region of the region to be processed of the workpiece 33 with high speed and high accuracy.

  Similarly, each irradiation head 9 is provided for each irradiation head 9 in accordance with the distance from the rotation center Q of each irradiation head 9 so that the difference between the peak intensity and the bias intensity becomes smaller for the irradiation head 9 provided on the outer peripheral side. Irradiation intensity information is calculated, and laser light is irradiated based on the irradiation waveform corresponding to the irradiation intensity information. For this reason, the pits P are formed in the entire region of the region to be processed of the workpiece 33 with high speed and high accuracy.

  Note that both the adjustment of the irradiation intensity and the adjustment of the irradiation time may be performed, or only one of them may be adjusted.

In the processing routine shown in FIG. 7, the case where the recording method is a constant linear velocity has been described. However, when recording (rotation) is performed using the CAV method with a constant angular velocity, as described above, the optical pickup 10 As the distance from the rotation center Q of each of the plurality of irradiation heads 9 changes according to the movement from the inner peripheral side to the outer peripheral side by the stepping motor 30, processing in the region irradiated with laser light by each irradiation head 9. The speed of the object 33 changes. For this reason, in the case of the CLV method, the frequency of the clock signal in each irradiation head 9 is initially set for each irradiation head 9 regardless of the position of the optical pickup 10 in the radial direction of the workpiece 33. Although the processing is performed assuming that the frequency is a predetermined frequency, in the case of recording by the CAV method, the control unit 16 rotates the center Q of each irradiation head 9 as the optical pickup 10 moves from the inner circumference side to the outer circumference side. The frequency of the clock signal for each irradiation head 9 may be calculated based on the distance after the change in accordance with the change in the distance from, and output to the pulse generator 35.
The distance from the rotation center Q of each irradiation head 9 is, for example, the radial movement distance from the state where the optical pickup 10 is positioned at the reference position, and the spindle motor 11 every time the radial direction of the optical pickup 10 is performed. What is necessary is just to obtain | require by calculating according to rotation of.

(Second Embodiment)
In the first embodiment, the case where the laser beam irradiated from the irradiation heads 9 to the workpiece 33 is one recording laser beam is described. However, in the present embodiment, each irradiation head 9 is irradiated. A case where a plurality of laser beams are irradiated to the processing object 33 from will be described.

  In addition, since the processing apparatus 91 demonstrated in this Embodiment is the structure substantially the same as the processing apparatus 90 demonstrated in the said 1st Embodiment, the same code | symbol is provided to the same part and detailed description is given. Omitted.

  The processing apparatus 91 has substantially the same configuration as the processing apparatus 90 shown in FIG. The difference is the configuration of each irradiation head 9 provided in the optical pickup 10. The configuration of each irradiation head 9 of the processing apparatus 91 is shown in FIG.

As shown in FIG. 11, each irradiation head 9 (irradiation head 9 </ b> A and irradiation head 9 </ b> B) provided in the processing apparatus 91 has a configuration of the irradiation head 9 in the processing apparatus 90 as shown in FIG. 11. In addition, a diffraction grating 58 is further provided.
Specifically, each irradiation head 9 is provided with a laser diode 53, an optical system 55, a light receiving element 56, and a diffraction grating 58. As described in the first embodiment, the optical system 55 includes the polarizing beam splitter 59, the collimator lens 60, the quarter wavelength plate 61, and the objective lens 62.

The diffraction grating 58 is for branching the laser beam B emitted from the laser diode 53 into a plurality of laser beams, and may have any configuration as long as it has such a function. .
In the present embodiment, the diffraction grating 58 uses the laser beam B emitted from the laser diode 53 to change the reflectance of the recording laser beam M used for forming the pit P of the workpiece 33 and the reflectance on the workpiece 33. Is branched into a detection laser beam S1 and a detection laser beam S2.
In this diffraction grating 58, the pit P can be formed on the workpiece 33 only by the recording laser beam M, and the pit P can be formed for the other detection laser beam S1 and detection laser beam S2. In order to make it difficult, the wavelength of the recording laser light M becomes a wavelength at which the pit P can be formed, and the wavelengths of the other detection laser light S1 and the detection laser light S2 become wavelengths at which the pit P cannot be formed. Thus, it is assumed that the installation position has been adjusted in advance.

  In this embodiment, the diffraction grating 58 describes a case in which the laser beam B is branched into a total of three laser beams of the recording laser beam M and the two detection laser beams. There may be a plurality of M, and the number of sub beams may be two or more.

  Further, in the present embodiment, the laser beam B emitted from the laser diode 53 is branched by the diffraction grating 58, so that the laser beam B is detected on the inner peripheral side at a predetermined interval from the region irradiated with the recording laser beam M. It is assumed that the diffraction grating 58 is adjusted in advance so that the laser beam S1 is irradiated and the detection laser beam S2 is irradiated on the outer peripheral side at a predetermined interval from the region irradiated with the recording laser beam M. . The predetermined interval is a pit P to be formed between the detection laser beam M and the recording laser beam M adjacent to the upstream side in the moving direction of the optical pickup 10 from the viewpoint of improving accuracy in detection processing described later. It is preferable that the distance is set in advance so as to be less than the distance in the radial direction. Further, the distance between the detection laser beam and the recording laser beam M adjacent to the downstream side in the moving direction of the optical pickup 10 is set in advance so as to be equal to the distance in the radial direction of the pits P to be formed. It is preferable that

Each of the recording laser beam M, the detection laser beam S1, and the detection laser beam S2 irradiated onto the workpiece 33 is reflected by the surface of the workpiece 33, and again the objective lens 62, After passing through the quarter-wave plate 61 and the collimator lens 60, it is reflected by the polarization beam splitter 59, passes through the cylindrical lens 63, and enters the light receiving element 56. The light receiving element 56 outputs a signal indicating the position of the beam received by the light receiving element 56 and the amount of received light to the amplifier 12 (see FIG. 3), and the light reception signal is sent to the control unit 16 and the servo circuit 13 via the amplifier 12. It comes to be supplied.
In the control unit 16, the irradiation head 9 corresponding to the beam incident on the light receiving element 56 and the recording laser emitted from the irradiation head 9 based on the input signal indicating the position of the beam received by the light receiving element 56 and the received light quantity. The light M, the detection laser light S1, and the detection laser light S2 are identified, and the stepping motor 30 is controlled based on the identification result.

  Here, in the processing apparatus 91 of the present embodiment, the optical pickup 10 is placed on the processing target 33 by the stepping motor 30 in the radial direction of the processing target 33 as in the processing apparatus 90 described in the first embodiment. The pits P are formed in the region of the processing target region of the processing target 33 by sequentially moving from the inner peripheral side to the outer peripheral side, or from the outer peripheral side to the inner peripheral side. Specifically, when the moving direction of the optical pickup 10 is a direction from the inner periphery side to the outer periphery side of the workpiece 33, as shown in FIG. By irradiating the laser beam while moving the optical pickup 10 in the radial direction (refer to the arrow Y direction in FIG. 16) toward the side, pits P are formed in the entire region 33P of the workpiece 33. It is formed.

  When the radial length of the optical pickup 10 is a length that covers one end to the other end of the radial length in the processing target region 33P of the processing target 33, each irradiation head provided in the optical pickup 10 9, while continuing the recording process of forming the pits P by irradiating laser light from 9, the optical pickup 10 is gradually moved from the outer peripheral side to the inner peripheral side or from the inner peripheral side to the outer peripheral side, Pits P are formed in the entire area 33P. However, when the radial length of the optical pickup 10 is a length that covers only a part of the processing target region 33P in the radial direction (for example, see FIG. 4), recording is performed by each irradiation head 9. When the optical pickup 10 including the plurality of irradiation heads 9 is gradually moved from the inner peripheral side to the outer peripheral side or from the outer peripheral side to the inner peripheral side, the optical pickup 10 in the plurality of irradiation heads 9 moves upstream in the moving direction. The irradiation head 9A arranged on the side reaches the area where the pits P are already formed by the irradiation head 9B arranged on the downstream side in the movement direction. In this case, if the optical pickup 10 is continuously moved in the radial direction while recording, the pits P are formed in an overlapping manner, which is not preferable.

  Therefore, if the pit P is formed by irradiating the laser beam from each irradiation head 9 while the optical pickup 10 moves from the inner peripheral side toward the outer peripheral side, in the processing apparatus 91 of the present embodiment, Immediately before the irradiation head 9A on the inner peripheral side reaches the area where the pits P are already formed by the irradiation head 9B on the outer peripheral side on the workpiece 33, each irradiation head 9 already has The recorded area where the pits P are formed is detected. When the recorded area is detected, the recording process for forming the pits P by the respective irradiation heads 9 is temporarily stopped while the optical pickup 10 is gradually moved in the moving direction (from the inner circumference side toward the outer circumference side). Then, after the optical pickup 10 is moved in the moving direction by the length in the radial direction of the recorded area, recording is started again.

  As a result, recording can be performed at high speed, and the pits P can be accurately formed on the workpiece 33.

Below, the process performed by the control part 16 of the processing apparatus 91 of this Embodiment is demonstrated.
In the control unit 16, the processing routine shown in FIG. 7 is executed as in the first embodiment, but after the rotation start instruction signal output processing of step 220 is performed in the processing routine shown in FIG. 7, the processing ends. In the meantime, the processing routine shown in FIG. 15 is executed as interrupt processing. In the following processing routine, in the processing apparatus 91, the laser beam is irradiated from each irradiation head 9 while the optical pickup 10 is gradually moved from the rotation center Q of the workpiece 33 toward the outer peripheral side. A description will be given on the assumption that the pits P are formed on the workpiece 33.

That is, the control unit 16 executes the interrupt processing routine shown in FIG. 15 every predetermined time, and proceeds to step 300.
In step 300, in the plurality of irradiation heads 9 provided in the optical pickup 10, there is an already recorded area on the outer peripheral side of the area where the workpiece 33 is recorded (downstream in the moving direction of the optical pickup 10). Whether or not this is detected is determined. If the determination is negative, the interrupt processing is terminated. If the determination is affirmative, the process proceeds to step 302.

  The determination in step 300 is a recording used for recording among a plurality of laser beams (recording laser beam M, detection laser S1, detection laser S2) emitted from each irradiation head 9 to the workpiece 33. When the reflected light from the detection laser S2 irradiated to the outermost periphery among the plurality of detection lasers other than the laser beam M for scanning is read, and the intensity change of the reflected light indicates an intensity change based on the pit P In addition, it may be determined that a recorded area has been detected.

  As the intensity change of the reflected light, for example, as the intensity of the reflected light by the processing object 33 of the detection laser S1 and the detection laser S2, the detection laser S2 in the region where the pits P of the processing object 33 are not formed. Is measured, and the intensity of the reflected light when the detection laser S2 is irradiated to the region where the pit P is formed is measured, and the intensity of the pit P is determined from the intensity of the reflected light. An intensity threshold for determining the formation region is determined. Then, when the intensity of the reflected light from the workpiece 33 of the detection laser S2 is less than the threshold value, it may be determined that the pit P formed region has been determined.

In the next step 302, a primary stop instruction signal indicating that the formation of the pits P due to the irradiation of the laser beams from the plurality of irradiation heads 9 is temporarily stopped is output to the pulse generator 35 and is necessary for the formation of the pits P. The laser power control circuit 20 outputs a signal for irradiating a laser beam having an irradiation intensity lower than the irradiation intensity. The pulse generator 35 that has received the primary stop signal temporarily stops transmission of the synchronization signal to the laser driver 19. For this reason, the transmission of the correction waveform signal from each laser driver 19 to each irradiation head 9 is temporarily stopped, and the formation of the pits P is temporarily stopped.
Further, the laser power control circuit 20 that has received a signal for irradiating a laser beam having an irradiation intensity lower than the irradiation intensity necessary for forming the pit P outputs the signal to the laser driver 19. The laser driver 19 that has received the signal controls the laser diode 53 so that the laser light having the irradiation intensity input from the laser power control circuit 20 is emitted from the laser diode 53.

  In the next step 304, a movement start instruction signal indicating that the optical pickup 10 is moved in the radial direction toward the downstream side in the movement direction (in this embodiment, from the inner circumference side to the outer circumference side) is output to the motor controller 32. . The input movement start instruction signal is output to the stepping motor 30 via the motor driver 31. The stepping motor 30 that has received the movement start instruction signal performs a movement process for moving the optical pickup 10 toward the downstream side in the movement direction.

  In the next step 306, in the plurality of irradiation heads 9 provided in the optical pickup 10, it is determined whether or not an unrecorded area is detected on the upstream side in the moving direction of the optical pickup 10, that is, on the inner peripheral side. And repeat negative judgment until affirmative.

  In step 306, the detection beam S <b> 1 provided on the upstream side (inner circumference side) of each irradiation head 9 in the movement direction while moving the optical pickup 10 in the movement direction (from the inner circumference side toward the outer circumference side). After the intensity change of the reflected light is read and the intensity change of the reflected light indicates the intensity change based on the pit P for a predetermined time, when the area where the pit P is not formed is detected, What is necessary is just to discriminate | determine that the recording area was detected.

In the next step 306, a signal indicating resumption of recording is output. Specifically, the process of step 306 is to form pits P by irradiating laser beams from a plurality of irradiation heads 9 in order to resume the recording process that was temporarily stopped by the process of the abandoned lady P302. A restart signal indicating restart is output to the pulse generator 35.
The pulse generator 35 that has received the restart signal temporarily stops transmission of the synchronization signal to the laser driver 19. For this reason, the sending of the correction waveform signal from each laser driver 19 to each irradiation head 9 is resumed, and the formation of the pits P is resumed.

  When the interrupt processing routine shown in FIG. 15 is executed, for example, when the optical pickup 10 is moved in the direction from the inner circumference side to the outer circumference side of the workpiece 33 as the movement direction, as shown in FIG. In addition, the workpiece 33 is rotated while the irradiation head 9 irradiates the laser beam from a state where the optical pickup 10 is positioned at a position where the pit P can be formed on the innermost peripheral side of the workpiece region 33P. Thus, as shown in FIG. 12, a plurality of pits P1 are sequentially formed in the rotation direction X of the workpiece 33 by the irradiation head 9A and the irradiation head 9B (not shown) (see FIG. 12).

  Furthermore, while the optical pickup 10 is moved in the moving direction, a plurality of pits P2 are formed in this order in the rotation direction X of the workpiece 33 by the irradiation head 9A and the irradiation head 9B (not shown). A plurality of pits P2 are formed in a region adjacent to the outer peripheral side of the plurality of formed pits P1 (see FIG. 13).

  By repeating this operation, pits are formed in order from the inner peripheral side by each irradiation head 9, and as shown in FIG. 14, the irradiating head 9A on the inner peripheral side is formed by the irradiation head 9B on the outer peripheral side. When the position adjacent to the inner peripheral side of P is irradiated with the laser beam, the pit P4 is detected by the detection laser S2, and the optical pickup 10 does not have a region to be irradiated by each irradiation head 9. It moves to the outer peripheral side until it reaches the recording area (see FIG. 17). Then, after the movement, the pit formation by each irradiation head 9 is resumed.

  As described above, according to the processing apparatus 91 of the present embodiment, the inner peripheral irradiation head 9A reaches the region where the pit P is already formed by the outer peripheral irradiation head 9B on the workpiece 33. Immediately before the recording, in each irradiation head 9, a recorded area on the downstream side in the moving direction of the optical pickup 10 is detected. When the recorded area is detected, the recording process for forming the pits P by the respective irradiation heads 9 is temporarily stopped while the optical pickup 10 is gradually moved in the moving direction (from the inner circumference side toward the outer circumference side). Then, the optical pickup 10 is moved in the moving direction in the radial direction length of the recorded area so that the laser beam emitted from the irradiation head 9A arranged on the most upstream side in the moving direction is irradiated to the unrecorded area. After moving the distance, recording is started again. Therefore, pits can be formed at high speed, and pits can be formed with high accuracy and efficiency over the entire region 33P to be processed 33.

It is a fragmentary sectional view which shows an example of the layer structure of the workpiece used in 1st Embodiment. It is a fragmentary sectional view which shows an example of the layer structure of the workpiece used in 1st Embodiment. It is the block diagram which showed typically the structure of the processing apparatus of 1st Embodiment. It is a schematic diagram which shows the one aspect | mode of the positional relationship of the processing target object and optical pick-up used in 1st Embodiment. It is a schematic diagram which shows the one aspect | mode of the positional relationship of the processing target object and optical pick-up used in 1st Embodiment. It is the block diagram which showed typically the structure of the irradiation head in the processing apparatus of 1st Embodiment. It is a flowchart which shows the process performed with the processing apparatus of 1st Embodiment. (A)-(C) are the schematic diagrams which show the clock signal produced | generated for each irradiation head in the processing apparatus of 1st Embodiment. (A) is a schematic diagram showing a pit to be formed, (B) is a schematic diagram showing a clock signal used in the irradiation head when forming this pit, and (C) to (G) are It is a schematic diagram which shows an example of the form of the irradiation waveform used synchronizing with the clock signal shown by (B) in order to form the pit shown by (A). It is a schematic diagram which shows an example of the relationship between peak intensity and bias intensity as adjustment of irradiation intensity. It is the block diagram which showed typically the structure of the irradiation head in the processing apparatus used by 2nd Embodiment. It is a schematic diagram which shows the pit formation and detection aspect by each irradiation head in 2nd Embodiment. It is a schematic diagram which shows the pit formation and detection aspect by each irradiation head in 2nd Embodiment. It is a schematic diagram which shows the pit formation and detection aspect by each irradiation head in 2nd Embodiment. It is a flowchart which shows the interruption process performed in the processing apparatus of 2nd Embodiment. It is a schematic diagram which shows the one aspect | mode of the positional relationship of the processing target used in 2nd Embodiment, and an optical pick-up. It is a schematic diagram which shows the one aspect | mode of the positional relationship of the processing target used in 2nd Embodiment, and an optical pick-up.

Explanation of symbols

9 Irradiation Head 9A Irradiation Head 9B Irradiation Head 10 Optical Pickup 16 Control Unit 18 Strategy Circuit 18A Strategy Circuit 18B Strategy Circuit 19 Laser Driver 19A Laser Driver 19B Laser Driver 20 Laser Power Control Circuit 20A Laser Power Control Circuit 20B Laser Power Control Circuit 33 Processing Object 33B Recording material layer 35 Pulse generation unit 35A Pulse generation unit 35B Pulse generation unit 55 Optical system 58 Diffraction grating 90 Processing device 91 Processing device

Claims (8)

Rotating means for rotating a member to be processed having a heat mode type recording material layer in which information is recorded by heat generated by irradiation of at least a recording laser beam;
A plurality of irradiations that irradiate recording laser beams onto regions that are arranged on a straight line passing through the rotation center of the processing target member rotated by the rotating means and that have different radial distances from the rotation center of the processing target member. Means,
A processing device with   The plurality of irradiation means are arranged at a predetermined interval, and the predetermined interval is a distance from one end portion to the other end portion in the radial direction around the rotation center in a predetermined processing target region of the processing target member. The processing apparatus according to claim 1, wherein the processing apparatus is a value divided by the number of irradiation means.   Formed by each of the plurality of irradiation means when a formation pattern corresponding to a predetermined formation target pattern is formed by each of the plurality of irradiation means on the processing target member rotated by the rotation means. A control means for controlling the irradiation time and intensity of the recording laser light emitted from each of the plurality of irradiation means so that the size and shape of the formed pattern are the same as each other. The processing apparatus according to claim 2. A plurality of irradiation waveform generating means provided corresponding to each of the plurality of irradiation means, and generating an irradiation waveform;
A plurality of synchronization signal generating means provided corresponding to each of the plurality of irradiation means and generating a synchronization signal;
With
The plurality of irradiation means are synchronized with the synchronization signal input from the corresponding synchronization signal generation means, and the recording laser light of intensity and irradiation time according to the irradiation waveform input from the corresponding irradiation waveform generation means Irradiate
The control means predetermines a synchronization signal to be output to the reference irradiation means as one of the plurality of irradiation means as a reference irradiation means, and outputs the reference synchronization signal to the reference irradiation means. The synchronizing signal generating means is controlled at the same time, and the frequency of the synchronizing signal increases as the distance increases toward the outer peripheral side according to the distance from the reference irradiation means, and the synchronizing signal increases as the distance increases toward the inner peripheral side. By controlling the synchronization signal generating means so that the frequency of the signal is lowered, the irradiation time of the recording laser light emitted from each of the plurality of irradiation means is controlled for each irradiation means. The processing apparatus according to claim 3. Irradiation intensity adjusting means for adjusting the ratio of the maximum irradiation intensity to the minimum irradiation intensity indicated by the irradiation waveform,
The control means defines one of the plurality of irradiation means as a reference irradiation means, and the minimum irradiation intensity indicated by the irradiation waveform as the distance increases toward the outer peripheral side according to the distance from the reference irradiation means. The irradiation intensity adjusting means is controlled so that the ratio of the maximum irradiation intensity with respect to the minimum irradiation intensity indicated by the irradiation waveform increases as the ratio of the maximum irradiation intensity with respect to decreases and the distance increases toward the inner periphery. 5. The processing apparatus according to claim 4, wherein the irradiation intensity of the recording laser beam is controlled for each irradiation unit. A moving means for relatively moving the plurality of irradiation means from the inner peripheral side of the processing target member toward the outer peripheral side or from the outer peripheral side of the processing target member toward the inner peripheral side;
The irradiation means includes
A light source that emits laser light;
Branching means for branching the laser beam emitted from the light source into at least the recording laser beam and a detection laser beam for detecting a reflectance on the processing target member;
Detecting means for detecting a change in the amount of reflected light from the processing target member of the laser beam for detection;
With
The control means is configured to move the plurality of irradiation means to an area where the recording area is not detected when a recorded area is detected on the processing target member based on a detection result by the detection means. The processing apparatus according to any one of claims 1 to 5, wherein the moving means is controlled.   Condensing means for condensing the recording laser light branched by the branching means and the detection laser light so as to be irradiated with a predetermined interval in the radial direction of the workpiece. The processing apparatus according to claim 6.   The branching means branches the laser light emitted from the light source into at least one or more laser lights and at least one or more detection laser lights. The processing apparatus as described.

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