WO2010024144A1

WO2010024144A1 - Working apparatus

Info

Publication number: WO2010024144A1
Application number: PCT/JP2009/064399
Authority: WO
Inventors: 唯吉良
Original assignee: 富士フイルム株式会社
Priority date: 2008-08-29
Filing date: 2009-08-17
Publication date: 2010-03-04
Also published as: JP2010055726A; TW201012581A

Abstract

Provided is a working apparatus capable of working a pattern at a high speed on a member to be worked having a heat mode type recording material layer. The member to be worked is irradiated with laser beams individually by a plurality of irradiation heads mounted on an optical pickup, so that pits are formed in the recording material layer. As a result, the recording speed can be further increased, as compared with the case, in which the pits are formed by only one irradiation head.

Description

Processing equipment

The present invention relates to a processing apparatus. The present invention particularly relates to a processing apparatus that performs processing on a processing target member having a heat mode type recording material layer.

2. Description of the Related Art Conventionally, a processing apparatus that forms a predetermined pattern on a processing target by irradiating the processing target with laser light is known. As such a processing apparatus, there is known an apparatus that performs processing by driving two orthogonal sliders to move a processing object placed on an XY table in the X direction and the Y direction. Further, as such a processing apparatus, an apparatus that performs laser processing while rotating a processing object by a rotating body by combining a rotating body and an optical system is known. For example, in Japanese Patent Application Laid-Open No. 2007-216263, for the purpose of high-precision processing, a method of performing laser processing while rotating an object to be processed, and adjusting the light intensity distribution of a laser beam spot, A method of forming a fine pattern having a diameter equal to or less than the diameter of a beam spot on a workpiece is disclosed. Also, WO 2004/047096 discloses a technique for forming a fine pattern corresponding to a concavo-convex pattern to be formed by irradiating a recording laser beam.

Developed as a processing object on which such a fine pattern is formed has been developed to various objects. In addition, a heat mode type recording material layer may be selected as a processing object for forming a fine pattern. The heat mode type recording material layer is a layer in which a desired pattern is formed by causing a physical change or a chemical change by photothermal conversion by irradiation. In other words, the heat mode type recording material layer dissipates the heat generated when the irradiation speed is slow, and requires a lot of irradiation energy. Has a characteristic of lowering. Therefore, when a pattern is formed (recorded) on the heat mode type recording material layer by irradiation, it is necessary to form the pattern at a high speed by short-time irradiation.

The present invention provides a processing apparatus for performing pattern irradiation at high speed on a processing target member having a heat mode type recording material layer.

According to a first aspect of the present invention, there is provided a rotating unit for rotating a processing target member having a heat mode type recording material layer on which information is recorded by heat generated by irradiation of a recording laser beam, and the processing that is being rotated. A plurality of irradiation units that are arranged on a straight line passing through the rotation center of the target member and irradiate recording laser beams to regions having different radial distances from the rotation center of the processing target member. is there.

According to a second aspect of the present invention, in the first aspect, the plurality of irradiation units are arranged at a predetermined interval, and the predetermined interval is the rotation center in a predetermined processing target region of the processing target member. It is a processing apparatus which is the value which divided the distance from the one end part of radial direction which makes a center to the other end part by the number of the said irradiation parts.

According to a third aspect of the present invention, in the first aspect, formation according to a predetermined formation target pattern is performed by each of the plurality of irradiation units on the processing target member rotated by the rotation unit. Irradiation of recording laser light emitted from each of the plurality of irradiation units so that the size and shape of the formed pattern formed by each of the plurality of irradiation units are the same when the pattern is formed It is a processing apparatus provided with the control part which controls time and irradiation intensity.

According to a fourth aspect of the present invention, in the third aspect, a plurality of irradiation waveform generation units that are provided corresponding to each of the plurality of irradiation units and generate an irradiation waveform, and each of the plurality of irradiation units And a plurality of synchronization signal generation units that generate synchronization signals, and the plurality of irradiation units correspond to the synchronization signals input from the corresponding synchronization signal generation units. Irradiating a recording laser beam having an intensity and an irradiation time corresponding to the irradiation waveform input from the irradiation waveform generation unit, and the control unit uses the one of the plurality of irradiation units as a reference irradiation unit. The synchronization signal to be output to the unit is determined in advance as a reference synchronization signal, the synchronization signal generation unit is controlled to output the reference synchronization signal to the reference irradiation unit, and the distance according to the distance from the reference irradiation unit Is becoming larger toward the outer periphery. The synchronization signal generating unit is controlled so that the frequency of the synchronization signal is increased and the frequency of the synchronization signal is decreased as the frequency is increased toward the inner peripheral side, thereby irradiating from each of the plurality of irradiation units. It is a processing apparatus which controls the irradiation time of the recording laser beam for each irradiation unit.

According to a fifth aspect of the present invention, there is provided an irradiation intensity adjusting unit that adjusts a ratio of the maximum irradiation intensity to the minimum irradiation intensity indicated by the irradiation waveform in the fourth aspect, and the control unit includes the plurality of irradiations. One of the sections is defined as a reference irradiation section, and the ratio of the maximum irradiation intensity to the minimum irradiation intensity indicated by the irradiation waveform decreases as the distance increases toward the outer periphery side according to the distance from the reference irradiation section. By controlling the irradiation intensity adjustment unit so that the ratio of the maximum irradiation intensity to the minimum irradiation intensity indicated by the irradiation waveform increases as the distance increases toward the inner peripheral side, the recording laser light It is a processing apparatus which controls irradiation intensity for every irradiation part.

According to a sixth aspect of the present invention, in the first aspect, the plurality of irradiation units may be arranged such that the plurality of irradiation units are directed from the inner peripheral side to the outer peripheral side of the processing target member or from the outer peripheral side of the processing target member. A moving unit that relatively moves toward the side, and the irradiation unit includes a light source that emits a laser beam, a laser beam emitted from the light source, at least the recording laser beam, and a member to be processed A laser beam for detection for detecting the reflectance; a branching unit that branches into a laser beam; and a detection unit that detects a change in the amount of reflected light from the processing target member of the laser beam for detection. Based on the detection result by the detection unit, when the recorded area is detected on the processing target member, the moving unit is controlled to move the plurality of irradiation units to an area where the recording area is not detected. Processing equipment It is.

According to a seventh aspect of the present invention, in the sixth aspect, the recording laser beam branched by the branching portion and the detection laser beam have a predetermined interval in the radial direction of the workpiece. It is a processing apparatus provided with the condensing part which condenses so that it may be opened and irradiated.

According to an eighth aspect of the present invention, in the sixth or seventh aspect, the branching unit includes at least one or a plurality of laser beams and at least one or a plurality of detection laser beams emitted from the light source. It is a processing device that branches into light.

According to the present invention, it is possible to provide 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 at high speed.

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. It is a schematic diagram which shows the clock signal produced | generated for each irradiation head in the processing apparatus of 1st Embodiment. It is a schematic diagram showing an example of a pit to be formed, a clock signal used in an irradiation head when forming the pit, and a form of an irradiation waveform used in synchronization with the clock signal. 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.

(First embodiment)
The processing apparatus 90 (see FIG. 3) according to the present embodiment forms a pit P as a pattern on the processing target 33 by irradiating a recording laser beam onto one disk-shaped processing target 33. .

The processing object 33 is in the form of a single disk (disc shape). As shown in FIG. 1, the workpiece 33 has a structure in which a recording material layer 33B is laminated on a substrate 33A. In the present embodiment, a case will be described in which the workpiece 33 has a configuration in which a recording material layer 33B is stacked on a substrate 33A. However, the processing object 33 used in the processing apparatus 90 of the present embodiment only needs to have a configuration provided with at least a recording material layer 33B whose details will be described later, and may have a configuration only of the recording material layer 33B. . Further, the processing object 33 may have a configuration in which other layers are further laminated on the recording material layer 33B.

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, recording materials are widely used for recording layers such as optical recording disks. For example, recording materials such as cyanine, phthalocyanine, quinone, squarylium, azulenium, thiol complex, and merocyanine are used.

The recording material layer 33B in the present embodiment is preferably a dye type containing a dye as a recording substance. Accordingly, examples of the recording material contained in the recording material layer 33B include 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, organic materials can be easily formed by spin coating, and it is difficult to obtain a material having a low transition temperature. For this reason, it is preferable to employ 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 thereof 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.

In particular, the recording material layer 33B is preferably a dye type capable of recording information only once with a laser beam. An organic recording material can be dissolved in a solvent to form a film by spin coating or spray coating. Therefore, the organic recording material is excellent in productivity. 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. 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. If the extinction coefficient k is too low, the amount of light absorption decreases. For this reason, a large laser power is required, and the processing speed may be reduced.

Note that the recording material layer 33B needs to absorb light at the recording wavelength as described above. Accordingly, it is possible to appropriately select a dye or modify the structure according to the wavelength of a light source that emits laser light (corresponding to a laser diode 53 described later (see FIG. 6)).
For example, the appropriate dye is advantageously selected from a pentamethine cyanine dye, a heptamethine oxonol dye, a pentamethine oxonol dye, a phthalocyanine dye, a naphthalocyanine dye, etc. when the oscillation wavelength of the laser light source is around 780 nm. .

In addition, when the oscillation wavelength of the light source is around 660 nm, the appropriate dye is advantageously selected from a trimethine cyanine dye, a pentamethine oxonol dye, an azo dye, an azo metal complex dye, a pyromethene complex dye, and the like.

Furthermore, when the oscillation wavelength of the light source is around 405 nm, the appropriate dye is a monomethine cyanine dye, monomethine oxonol dye, zero methine merocyanine dye, phthalocyanine dye, azo dye, azo metal complex dye, porphyrin dye, arylidene dye, Advantageously, it is selected from complex dyes, coumarin dyes, azole derivatives, triazine derivatives, benzotriazole derivatives, 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, respectively. 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.
Further, the compounds (II-1 to II-8) represented by the chemical formulas 3 and 4 are compounds when the wavelength is around 660 nm. Further, the compounds (III-1 to III-14) indicated 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.

When the oscillation wavelength of the light source is around 780 nm, examples of the compounds constituting the recording material layer 33B 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.

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

JP-A-4-74690, JP-A-8-127174, JP-A-11-53758, JP-A-11-334204, JP-A-11-334205, JP-A-11-334206, The dyes described in JP-A-11-334207, JP-A-2000-43423, JP-A-2000-108513, JP-A-2000-158818, and the like are also preferably used.

The dye-type recording material layer 33B is formed by dissolving the dye in a suitable solvent together with a binder and the like to prepare a coating solution, coating the substrate 33A, forming a coating film, and drying. . The temperature of the surface on which the coating solution is applied is preferably in the range of 10 ° C. or higher and 40 ° C. or lower. More preferably, the lower limit is 15 ° C. or higher, and the upper limit is more preferably 35 ° C. or lower. Moreover, it is more preferable that it is 30 degrees C or less, and it is especially preferable that it is 27 degrees C or less. When the coated surface temperature is in 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. 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 the coating process a plurality of times.
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, and 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, Glycol ethers such as propylene glycol monomethyl ether; and the like.

The above solvents can be used alone or in combination of two or more in consideration of the solubility of the dye used. The coating solution may further contain various additives such as an antioxidant, a UV absorber, a plasticizer, and a lubricant depending on 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 of the recording material layer 33B, the amount of the binder used is generally in the range of 0.01 to 50 times (mass ratio) with respect to the dye, preferably 0.8. It is in the range of 1 to 5 times (mass ratio), and preferably in the range of 0.1 to 5 times (mass ratio).

Further, the recording material layer 33B may contain various browning preventive agents 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 can be formed by a film forming method such as vapor deposition, sputtering, or CVD in accordance with the physical properties of the recording material.

In addition, as for the dye, those having a high absorption rate at other wavelengths are employed in the wavelength of the laser light used for processing the pit P described 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 the infrared region.

The wavelength λw of the laser light for forming the pit P may be any wavelength that provides a laser power that is large enough to form the pit P due to the shape change in the heat mode. For example, when a dye is used for the recording material layer 33B, the wavelength λw of the laser light 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 described later) may be any laser such as a gas laser, a solid-state laser, or a semiconductor laser. However, it is preferable to employ a laser beam that can freely change the emission interval as the type of the laser beam. For example, it is preferable to employ a semiconductor laser as the type of laser light.

Also, the laser power (irradiation intensity) of the recording laser light is preferably higher 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.

It is preferable that the thickness of the recording material layer 33B corresponds to the depth of pits P described later. As thickness, it sets suitably in 1 nm or more and 10000 nm or less, for example. Further, the lower limit of the thickness is preferably 10 nm or more, and more preferably 30 nm or more. The reason is that if the thickness is too thin, the pits P are formed shallow. Therefore, it becomes 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. When the thickness is too thick, it becomes difficult to form the pits P as deep concave portions, which requires a large laser power, and the processing speed decreases.

Further, it is preferable that the thickness t of the recording material layer 33B and the diameter d of the pits P have 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 relation to the diameter d of the pit P is the same as that described above.

The recording material layer 33B is prepared by dissolving or dispersing a substance serving as a recording material in an appropriate solvent to prepare a coating solution, and then applying the coating solution to the substrate 33A by a coating method such as spin coating, dip coating, or extrusion coating. It is formed by applying on top.

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 recording laser light 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 light is absorbed by the recording material layer 33B, the absorbed light is converted into heat, and the temperature of the region irradiated with the light rises. Thereby, the recording material layer 33B causes one or both of chemical change and physical change such as softening, liquefaction, vaporization, sublimation, and decomposition. The material having such a change moves and disappears to form pits P.

Note that it is preferable that vaporization, sublimation, or decomposition of the recording material layer 33B has a large rate of change and is steep. 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%. More preferably, it is 20% or more. Further, the slope of weight reduction (weight reduction rate per 1 ° C. temperature rise) by the differential thermal balance (TG-DTA) during vaporization, sublimation or decomposition of the material constituting the recording material layer 33B is 0.1% / ° C. The above is preferable, more preferably 0.2% / ° C or more, and still more preferably 0.4% / ° C or more.

In addition, the upper limit of the transition temperature of at least one of chemical changes and physical changes such as softening, liquefaction, vaporization, sublimation, and decomposition is preferably 2000 ° C. or less, and more preferably 1000 ° C. or less. More preferably, it is 500 ° C. or lower. 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 the present embodiment will be described.

The processing apparatus 90 of the present embodiment forms pits P in the processing target 33 by irradiating the processing target 33 provided with the 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.

It should be noted that in the present embodiment, when the parts of the apparatus each having the same function are collectively described, the description is omitted. For example, as a strategy circuit, the processing apparatus 90 of the present embodiment is provided with two strategy circuits 18A and a strategy circuit 18B. However, when these are described generically, they will be described as the strategy circuit 18.

The spindle motor 11 is a motor that rotationally drives the workpiece 33, and the rotation speed is controlled by the servo circuit 13. The processing apparatus 90 in the present embodiment is a method for driving the processing object 33 at a constant angular velocity (CAV: Constant Angular Velocity) or a method for rotating the processing object 33 so as to have a constant recording linear velocity (CLV). : Constant Linear Velocity). 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 irradiates the processing target object 33 rotated by the spindle motor 11 with a recording laser beam. The optical pickup 10 includes a plurality of irradiation heads 9 so that different regions on the workpiece 33 can be irradiated with recording laser light. In the present embodiment, the “different region” means that the radial position (the shortest distance from the rotation center Q) is different when the rotation center Q of the workpiece 33 is the center. 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, a case will be described in which two

irradiation heads

9A and 9B are provided as a plurality of irradiation heads. The processing apparatus 90 may have a configuration in which a plurality (two or more) of irradiation heads 9 are provided, and may have a configuration in which three or more irradiation heads 9 are provided.

As shown in FIG. 4, these irradiation head 9 A and irradiation head 9 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 A and 9 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 described later. The stepping motor 30 is driven via the motor controller 32 and the motor driver 31 under the control of the control unit 16. Thus, the support member 17 is configured to be able to move the workpiece 33 in the radial direction while the irradiation head 9A and the irradiation head 9B supported by the support member 17 maintain the predetermined interval. .

The optical pickup 10 is moved in the radial direction by driving the stepping motor 30 while irradiating the processing target object 33 with the recording laser beam by each irradiation head 9. Thus, the pits P are formed over the entire surface of the predetermined processing target region 33P in the entire region of the processing target 33.

In the present embodiment, the irradiation head 9A and the irradiation head 9B are provided in a part of a region from one end portion to the other end portion in the radial direction in a predetermined processing target region 33P of the processing target 33. Explain the case. However, the plurality of irradiation heads 9 may be arranged at predetermined intervals over the entire region extending from the one end to the other end.

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 region 33P of the processing target 33 by the number of irradiation heads 9 provided in the optical pickup 10. Distance. 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 A and irradiation head 9 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. Each of these irradiation heads 9 has the same configuration.

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 19 A and laser driver 19 B), 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 of the workpiece 33. Collect light. Each irradiation head 9 transmits the laser beam reflected by the recording material layer 33B again through the objective lens 62, the quarter wavelength plate 61, and the collimator lens 60, and reflects the laser beam by the polarization beam splitter 59, thereby forming a cylindrical lens. The light is incident on the light receiving element 56 through 63. The light receiving element 56 outputs the received signal to the amplifier 12 (see FIG. 3). 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 the focus actuator 64 and the tracking actuator 65, and is configured to be movable in the optical axis direction of the laser light B and the radial direction of the light to be processed 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 a light reception signal supplied via the light receiving element 56 and the amplifier 12. The servo circuit 13 performs focus control and tracking control by moving the objective lens 62 as described above.

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). ) Or a method (CLV) of rotating the workpiece 33 so as to achieve 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. 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. The generated pit formation information is rearranged so that information generated in order from the innermost side to the outermost side of the region to be recorded by each irradiation head 9 is arranged.
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. The irradiation intensity information indicating the irradiation intensity is output to the laser power control circuit 20 connected to the corresponding irradiation head 9 (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.

The clock frequency information includes the length of the pit P formed by irradiating the recording material layer 33B of the rotating workpiece 33 with laser light for a period of N clocks (N is an integer of 1 or more). Even when the recording material layer 33B of the workpiece 33 is formed in different regions of the radial position by any one of the plurality of irradiation heads 9, the same length and shape are obtained. It is calculated according to the distance from the rotation center Q of each irradiation head 9 so that the clock frequency is higher (the clock cycle is shorter) as the irradiation head 9 is provided on the outermost periphery 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 peripheral side to the outer peripheral side or from the outer peripheral side to the inner peripheral side by the stepping motor 30, a plurality of The speed of the workpiece 33 in a region irradiated with laser light by each of the 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. Depending on the reference radial distance from the irradiation head 9A, the optical pickup 10 moves downstream from the irradiation head 9A in the moving direction (or 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 provided 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 A, an irradiation head 9 B, and an irradiation head 9 C are provided as a plurality of irradiation heads 9 on the optical pickup 10 from the inner peripheral side to the outer peripheral side of the workpiece 33. They are arranged so as to be arranged at predetermined intervals in the radial direction. 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. 8 (1), the irradiation head 9A arranged on the innermost peripheral side among the plurality of irradiation heads 9 is used as the reference irradiation head. Determine. A frequency F1 (clock signal period 1 / F1) is determined as the frequency of the clock signal T1 of the irradiation head 9A. Then, as shown in FIG. 8 (2), 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 set such that 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) (see FIG. 8 (3)).

Note that n represents an integer, and when the irradiation head 9A arranged on the innermost peripheral side is the “1” th irradiation head, the irradiation head 9 positioned first is used. 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 arranged on the innermost circumference 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 used as the reference clock frequency. It may be determined as

Note that when the workpiece 33 is recorded (rotated) by the CLV method with a constant linear velocity as described above, the speed of the workpiece 33 in the region irradiated with the laser light by each irradiation head 9 is the optical pickup 10. However, even if the position of each irradiation head 9 moves to the outer peripheral side while keeping the distance from each other by moving from the inner peripheral side to the outer peripheral side of the workpiece 33, it is the same as before the movement. For this reason, when recording by the CLV method, the control unit 16 clocks each irradiation head 9 based on the distance from the rotation center Q of each irradiation head 9 when the optical pickup 10 is positioned at the reference position. After the signal frequency is calculated, the frequency of the clock signal is not calculated again even if the optical pickup 10 moves to the outer peripheral side. Therefore, the control unit 16 uses the frequency of the clock signal calculated when the control unit 16 is positioned at the reference position so that the entire area of the processing target area 33P of the processing target object 33 is recorded by each irradiation head 9. adjust.

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. The distance from the rotation center Q of each changes. As a result, the speed of the workpiece 33 in the region irradiated with the laser light by each irradiation head 9 changes. For this reason, when recording by the CAV method, the control unit 16 changes the distance after the change from the rotation center Q of each irradiation head 9 with the movement of the optical pickup 10 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 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 laser 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 generation unit 35 includes a plurality of pulse generation units 35 corresponding to the respective irradiation heads 9. As shown in FIGS. 3 and 4, when two irradiation heads 9 A and 9 B are provided as the plurality of irradiation heads 9, the pulse generation unit 35 generates two pulses corresponding to each irradiation head 9. Part. Specifically, the pulse generation unit 35 is provided with a pulse generation unit 35A corresponding to the irradiation head 9A, and is provided with 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 of the corresponding laser driver 19A and laser Output to the 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. The laser power control circuit 20 is a laser of the recording laser light irradiated from the corresponding irradiation head 9 so that the recording laser light having the intensity of the irradiation intensity information indicating the irradiation intensity input from the control unit 16 is irradiated. Adjust the strength.

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 optical pickup 10 is described as moving from the inner peripheral side of the workpiece 33 toward the outer peripheral side. However, the optical pickup 10 moves from the outer peripheral side toward the inner peripheral side. Form may be sufficient.

The motor driver 31 rotationally drives 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. The control unit 16 is configured to control each unit of the processing apparatus 90 according to a program stored in the ROM, and to centrally control a recording process for the processing target object 33.

Next, processing 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.

When the processing object 33 is set in a slot (not shown) of the processing apparatus 90 and the power switch (not shown) of the processing apparatus 90 is operated to supply power to each section of the control section 16, the control section 16 The program for executing the processing routine shown in FIG. 7 stored in advance in the ROM in 16 is read and the routine proceeds to step 200.

It should be noted 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.

Further, 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.

Execution of the recording method by the CLV method is performed by any of the PCs 38 (see FIG. 3) connected to the control unit 16 so as to be able to send and receive signals after the power is supplied to each part of the apparatus and before the process of step 200 is executed. It is assumed that information indicating whether or not the method is input is executed by reading that the input information is information indicating the CLV method. Further, the control unit 16 is provided with an input / output unit such as a keyboard (not shown) for performing various operations, and the input / output unit is operated by an operator, so that either the CLV method or the CAV method is used. May be determined by determining the input signal. In addition, the input by the operator is provided with a display screen such as a monitor in advance so as to be able to send and receive signals to the control unit 16, and displays information for selecting a recording method on the display screen. What is necessary is just to comprise previously so that an operator can perform selection instruction | indication via an input part based on display information.

In step 200, recording data to be recorded on the recording material layer 33B of the processing object 33 is read from the memory 36. The recording 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 above. As a method of 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, based on the distance from the rotation center Q of each pit P read in the above step 202, the irradiation head 9 to be recorded with each pit P is specified.

In step 204, the irradiation head 9 that forms each pit P is specified. For example, as shown in FIG. 4, when the optical pickup 10 is provided with two

irradiation heads

9A and 9B, the optical pickup 10 is provided to be movable in the radial direction of the workpiece 33 by the stepping motor 30. ing. From this, there is an area from the innermost peripheral side in the processing target area 33P, which is an area excluding the non-processing target area around the rotation center Q of the processing target 33, to the radial center of the processing target area 33P. It becomes an irradiation object area | region by the irradiation head 9A provided in the inner peripheral side. And the area | region from the radial direction center part of the process target area | region 33P to an outer periphery 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 by each of these irradiation heads 9 the distance from the rotation stop Q of each pit P calculated in step 202 is determined, 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. In the next step 208, the derived irradiation intensity for each pit P is stored 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. Information. As shown in FIG. 10, the irradiation intensity 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 reduced as the irradiation time is increased, and the irradiation intensity may be adjusted so as to be increased as the irradiation time is shortened. For this reason, the irradiation time and the irradiation intensity may be determined appropriately based on the balance.

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 an integer of 1 or more) with respect to the recording material layer 33B of the rotating workpiece 33. When the shape and depth of the pits P formed by irradiating the laser beam for a period of () are formed in different regions on the workpiece 33 by any one of the plurality of irradiation heads 9. Even so, it is calculated according to the distance from the rotation center Q of each irradiation head 9 so as to have the same shape and depth.

Specifically, the irradiation intensity information is assumed to form pits P having the same shape and depth, and the peak intensity Pn with respect to the bias intensity Tn irradiated toward the irradiation head 9 provided on the outer peripheral side. What is necessary is just to calculate according to the distance from the rotation center Q of each irradiation head 9 so that ratio of these may become small.

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. “N” of Fn is “1” which is the initial value of the irradiation head 9 provided on the innermost peripheral side, and the irradiation heads 9 arranged from the irradiation head 9 to the outer peripheral side are respectively from the inner peripheral side. What is necessary is just to set the numerical value counted up in order.

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. The time from the rising to the falling 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 pit P is irradiated with the recording laser light whose irradiation intensity changes at a rate of change corresponding to the irradiation waveform, depending on the irradiation time and irradiation intensity of the irradiated recording laser light. The length, shape, and depth are formed.

The irradiation waveform is actually sent from the driver 19 to the irradiation head 9 in synchronization with the clock signal, thereby adjusting the time from the rising edge to the falling edge of the irradiation waveform. 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, the irradiation time of the recording laser light emitted from each irradiation head 9 is adjusted by adjusting the frequency of the clock signal in each irradiation head 9.

Further, the irradiation intensity of the recording laser light emitted from each irradiation head 9 is adjusted by adjusting the bias intensity and the peak intensity of the irradiation waveform according to the ratio of the peak intensity Pn to the bias intensity Tn as the irradiation intensity information. Is adjusted.

Here, in the recording material layer 33B to be formed by the processing apparatus 90 according to the present embodiment, the pits P are formed by the thermal energy generated by the laser light irradiation as described above. Therefore, the pit P is usually formed at the recording end point (downstream in the rotation direction of the workpiece 33) compared to the recording start point of each pit P (upstream in the rotation direction of the workpiece 33). The pit P to be used tends to be thick. Further, depending on the rotational speed of the workpiece 33 and the intensity of the irradiated laser light, the distance between the pits P may be close and connected.

Specifically, assuming that the clock cycle is T (see (2) in FIG. 9), for example, as an irradiation waveform for forming a pit P having a length of 3 × T (see (1) in FIG. 9), The laser beam is irradiated so that the irradiation amount change shown in the irradiation waveform having the pulse width (length from the rising edge to the falling edge) as shown in (3) of FIG. 9 is 3T. In this case, the pit P that is actually formed extends or rubs toward the downstream side in the rotation direction of the workpiece 33 (the arrow X direction in FIG. 9), and the pit P shape is different from the intended shape. It becomes a shape.

In order to prevent such a phenomenon, in the processing apparatus 90 of the present embodiment, the one-pulse type (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. (See (4)), a multi-pulse type (see (5) in FIG. 9) that is an irradiation waveform that falls in one clock cycle, or an L shape type (see (6) in FIG. 9) that is an L-type irradiation waveform. Alternatively, an irradiation waveform of a castle type ((7) in FIG. 9) in which the waveform is constituted by a top pulse, an intermediate bias portion, and a last pulse is used as appropriate.

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. The pit P recorded when the object 33 is irradiated may have a non-uniform thickness in the rotational direction X as described above, or may be connected to adjacent pits P, resulting in a shape change. The irradiation waveform information indicating the calculated irradiation waveform may be recorded 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. Corresponding irradiation waveform information is read from the memory 36. Accordingly, the control unit 16 stores, as the irradiation waveform information corresponding to each pitch P, information indicating the one-pulse type, information indicating the multi-pulse type, information indicating the L-shape type, or information indicating the castle type, in the memory 36. You can read from.

By the above processing, an irradiation waveform for forming an optimal 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 corresponding laser beam is irradiated, and the pit P is formed.

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 the 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 with respect to 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. It is calculated according to the distance from the rotation center Q of each irradiation head 9 so that the clock frequency becomes higher (the clock cycle is shorter) as the irradiation head 9 is present.

In the next step 216, 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 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. Next, a movement start signal is output 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 circumference side of the plurality of irradiation heads 9). The irradiation head 9 A is moved to a state where the irradiation head 9 A is positioned in the innermost peripheral region in the processing target region 33 P of the processing target 33.

In the next step 220, a rotation start instruction signal indicating the rotation start 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, the case where the rotation method (recording method) in the CLV method with a constant linear velocity is used as described above will be described. The rotation instruction signal includes information indicating the CLV method. From this, rotation with a constant linear velocity by the workpiece 33 is started by the rotation control of the spindle motor 11 based on the information.

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 each irradiation head information is read. Are output to the pulse generator 35A and the pulse generator 35B of the pulse generator 35 corresponding to the irradiation head 9.

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

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.

By the processing of step 22 and step 224, each of the pulse generation unit 35A and the pulse generation unit 35B provided in accordance with the corresponding irradiation head 9 of the pulse generation unit 35 corresponding to each irradiation head 9 stores the clock frequency information. A clock signal having a frequency is generated and output to each of the corresponding laser driver 19A and laser driver 19B.

Also, 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. Furthermore, in the laser power control circuit 20A and the laser power control circuit 20B, peak intensity information and bias intensity information included in the input irradiation intensity information are output to the corresponding laser driver 19A and laser driver 19B, respectively. .

Each laser driver 19A and laser driver 19B, to which the irradiation waveform, peak intensity information, and bias intensity information are input, has a peak of 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. The irradiation waveform is corrected so that it becomes the intensity and the bias intensity of the irradiation waveform becomes the bias intensity of the input bias intensity information. Thereafter, each laser driver 19A and laser driver 19B outputs the corrected irradiation waveform corrected to each of the corresponding irradiation head 9A and irradiation head 9B. The corrected irradiation waveforms are arranged on the innermost side of the plurality of pits P to be formed in each irradiation head 9 and arranged in the order in which they are formed in the rotation direction of the workpiece 33. Or it outputs to the laser driver 19 in order from the some pit P. FIG.

The irradiation head 9A and the irradiation head 9B, to which the corrected irradiation waveform and the clock signal are input, respectively synchronize the recording laser beam having the irradiation intensity corresponding to the voltage that changes according to the input correction irradiation waveform 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. If the determination is affirmative, this routine ends.

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 respectively input by executing the processing of the

above steps

222 and 224. The recording laser beam having the irradiation intensity corresponding to the voltage that changes according to the corrected irradiation waveform is irradiated in synchronization with the clock signal. Thus, the pits P are sequentially formed on the workpiece 33 from the inner peripheral side to the outer peripheral side. However, at this time, every time the pit P recording for one round is completed by each of the irradiation heads 9, the control unit 16 controls the stepping motor 30 via the motor controller 32 and the motor driver 31 to process it. The optical pickup 10 is moved from the radially inner periphery side of the object 33 toward the outer periphery 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 according to the present embodiment, the processing from step 200 to step 226 is executed. As a result, the processing object 33 is irradiated with laser light from each of the plurality of irradiation heads 9 provided in the optical pickup 10, whereby pits P are formed in the recording material layer 33B. Therefore, the processing apparatus 90 of the present embodiment can further increase the recording speed as compared with the case where the pits P are formed by only one irradiation head 9.

Further, in the processing apparatus 90 according to the present embodiment, the length of the pits P formed by irradiating the recording material layer 33B of the rotating processing object 33 with laser light for a predetermined clock period is as follows. Each of the plurality of irradiation heads 9 has the same length even if the irradiation head 9 is formed in a different region of the recording material layer 33B of the processing object 33 among the plurality of irradiation heads 9. Are individually controlled.
Specifically, in the processing apparatus 90 of the present embodiment, the irradiation head 9 provided on the outer peripheral side has a higher clock frequency (shorter clock cycle) than the rotation center Q of each irradiation head 9. The frequency of the clock signal is calculated for each irradiation head 9 according to the distance, and laser light is irradiated from each irradiation head 9 in synchronization with the clock signal. From this, the irradiation time of the laser light irradiated from each irradiation head 9 is easily adjusted with a simple configuration for each irradiation head 9. For this reason, the pits P are formed at high speed and with high accuracy in the entire region of the region to be processed of the workpiece 33.

Similarly, in the processing apparatus 90 according to the present embodiment, the irradiation head 9 provided on the outer peripheral side is closer to the rotation center Q of each irradiation head 9 so that the difference between the peak intensity and the bias intensity becomes smaller. Irradiation intensity information is calculated for each irradiation head 9 according to the distance, and laser light based on the irradiation waveform corresponding to the irradiation intensity information is irradiated. For this reason, the pits P are formed at high speed and with high accuracy in the entire region of the region to be processed of the workpiece 33.

In addition, both the adjustment of the irradiation intensity and the adjustment of the irradiation time may be adjusted, 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 by the CAV method with a constant angular velocity, as described above, 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. The distance from the rotation center Q of each changes. As a result, the speed of the workpiece 33 in the region irradiated with the laser light by each irradiation head 9 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. The processing was performed assuming that the frequency was a predetermined frequency. However, when recording by the CAV method, the control unit 16 changes the distance after the change 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 distance 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 is moved each time the optical pickup 10 is moved in the radial direction. What is necessary is just to obtain | require by calculating according to rotation.

(Second Embodiment)
In the first embodiment, the case has been described in which the laser light emitted from each irradiation head 9 to the workpiece 33 is one recording laser light. However, in the present embodiment, a case will be described in which a plurality of laser beams are irradiated from each irradiation head 9 to the workpiece 33.

Note that the processing device 91 described in the present embodiment has substantially the same configuration as the processing device 90 described in the first embodiment. For this reason, the same code | symbol is attached | subjected to the same part and detailed description is abbreviate | 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 of the irradiation heads 9 (irradiation head 9A and irradiation head 9B) provided in the processing apparatus 91 includes, in addition to the configuration of the irradiation head 9 in the processing apparatus 90, as shown in FIG. A diffraction grating 58 is 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. Therefore, the diffraction grating 58 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.
The installation position of the diffraction grating 58 is adjusted in advance so that the pits P can be formed on the workpiece 33 only by the recording laser beam M. Further, in the diffraction grating 58, the wavelength of the recording laser beam M is such that the pit P can be formed so that it is difficult to form the pit P for the other detection laser beam S1 and the detection laser beam S2. In addition, the installation positions are adjusted in advance so that the wavelengths of the other detection laser light S1 and detection laser light S2 are wavelengths at which the pits P cannot be formed.

In the present embodiment, the case where the diffraction grating 58 branches the laser beam B into a total of three laser beams of the recording laser beam M and the two detection laser beams will be described. However, there may be a plurality of recording laser beams M, and there may be two or more sub beams.

In this embodiment, the laser beam B emitted from the laser diode 53 is branched by the diffraction grating 58. As a result, the diffraction grating 58 is irradiated with the detection laser light S1 on the inner peripheral side at a predetermined interval from the region irradiated with the recording laser light M, and is predetermined from the region irradiated with the recording laser light M. Adjustment is made in advance so that the laser beam S2 for detection is irradiated on the outer peripheral side with an interval. As the predetermined interval, from the viewpoint of improving accuracy in the detection process described later, the distance between the detection laser beam and the recording laser beam M adjacent to the upstream side in the moving direction of the optical pickup 10 is the radial direction of the pit P to be formed It is preferable that the distance is set in advance so that the distance is less than the distance of. Further, the distance between the detection laser light and the recording laser light 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.

Each of the recording laser beam M, the detection laser beam S1, and the detection laser beam S2 irradiated on the workpiece 33 is reflected by the surface of the workpiece 33, and again the

objective lenses

62, 1 / After passing through the four-wavelength 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). The light reception signal is supplied to the control unit 16 and the servo circuit 13 via the amplifier 12.
The control unit 16 irradiates 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 amount. The light M, the detection laser light S1, and the detection laser light S2 are identified. The control unit 16 controls the stepping motor 30 based on the identification result.

Here, in the machining apparatus 91 of the present embodiment, the pit P is formed on the workpiece 33 by the stepping motor 30 on the workpiece 33 as in the machining apparatus 90 described in the first embodiment. By sequentially moving from the inner peripheral side to the outer peripheral side or from the outer peripheral side to the inner peripheral side in the radial direction of 33, the processing target object 33 is formed in the region to be processed. Specifically, when the moving direction of the optical pickup 10 is a direction from the inner peripheral side to the outer peripheral side of the workpiece 33, the pit P has a rotation center Q of the workpiece 33 as shown in FIG. The optical pickup 10 is irradiated in the radial direction (see the arrow Y direction in FIG. 16) from the outer periphery to the outer peripheral side, and is formed in the entire region of the processing target region 33P of the processing target 33 by being irradiated with laser light. Is done.

When the radial length of the optical pickup 10 is a length that covers the other end of the radial length in the processing target region 33P of the processing target 33, the pit P is irradiated with each irradiation provided in the optical pickup 10. While continuing the recording process for forming the pits P by irradiating the laser beam from the head 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, and the processing target region 33P It is formed in the whole area. 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 (see, for example, FIG. 4), while performing recording by each irradiation head 9, If the optical pickup 10 having a 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 upstream side in the movement direction of the optical pickups 10 in the plurality of irradiation heads 9 The irradiation head 9 A arranged at the position reaches the area where the pits P are already formed by the irradiation head 9 B arranged downstream 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, when 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, the processing apparatus 91 of the present embodiment The irradiating head 9A has already pits on the outer peripheral side of the optical pickup 10 in each irradiating head 9 immediately before reaching the area where the pit P is already formed by the outer irradiating head 9B on the workpiece 33. A recorded area where P is formed is detected. When the recorded area is detected, the processing device 91 according to the present embodiment gradually moves the optical pickup 10 in the movement direction (from the inner circumference side toward the outer circumference side), and the pits P are generated by the irradiation heads 9. Is temporarily stopped, the optical pickup 10 is moved in the moving direction by the length in the radial direction of the recorded area, and then recording is started again.

Thereby, the processing apparatus 91 of the present embodiment can perform recording at a high speed and form the pits P on the processing object 33 with high accuracy.

Below, the process performed by the control part 16 of the processing apparatus 91 of this Embodiment is demonstrated.
As in the first embodiment, the control unit 16 executes the processing routine shown in FIG. However, the control unit 16 of the processing apparatus 91 according to the present embodiment performs the processing shown in FIG. 15 after the rotation start instruction signal output processing of step 220 in the processing routine shown in FIG. The routine is executed as an interrupt process. In the following processing routine, the processing apparatus 91 performs processing by irradiating laser light from each irradiation head 9 while the optical pickup 10 is gradually moved from the rotation center Q of the processing target 33 toward the outer peripheral side. A description will be given assuming that the pits P are formed on the object 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). It is determined whether or not this is detected. If the determination is negative, the interrupt process ends. On the other hand, if the determination is affirmative, the processing routine 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 Then, it is determined that a recorded area has been detected.

For example, the following processing is performed as the determination of the intensity change of the reflected light. That is, as the intensity of the reflected light from the processing object 33 of the detection laser S1 and the detection laser S2, the reflected light when the detection laser S2 is irradiated to the area where the pit P of the processing object 33 is not formed. The intensity and the intensity of the reflected light when the detection laser S2 is irradiated onto the area where the pits P are formed are measured. Next, an intensity threshold value for determining the formation area of the pit P from the intensity of the reflected light is determined. When the intensity of the reflected light from the processing object 33 of the detection laser S2 is less than the threshold value, it is 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 by the irradiation of the laser beams from the plurality of irradiation heads 9 is temporarily stopped is output to the pulse generation unit 35. At the same time, in step 302, a signal for irradiating laser light having an irradiation intensity lower than the irradiation intensity necessary for forming the pit P is output to the laser power control circuit 20. 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 sending 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.
In addition, 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 the present 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 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). In the case where an area where no pit P is formed is detected 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, it is not recorded on the inner circumference side. This is done by determining that a region has been detected.

In the next step 306, a signal indicating resumption of recording is output. Specifically, in the process of step 306, in order to resume the recording process that was temporarily stopped in the process of the abandoned lady P302, formation of pits P by irradiating laser beams from a plurality of irradiation heads 9 is performed. 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.

The following processing is performed by executing the interrupt processing routine shown in FIG. That is, for example, the optical pickup 10 moves in a direction from the inner peripheral side to the outer peripheral side of the workpiece 33. Next, as shown in FIG. 16, from the state where the optical pickup 10 is positioned at a position where the pits P can be formed on the innermost peripheral side of the processing target region 33P, the irradiation head 9 irradiates laser light, The workpiece 33 rotates. Thus, 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).

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

By repeating the above operation, pits are formed in order from the inner peripheral side by each irradiation head 9. Next, as shown in FIG. 14, when the inner peripheral irradiation head 9A reaches the position where the laser beam is irradiated to the region adjacent to the inner peripheral side of the pit P formed by the outer peripheral irradiation head 9B, The pit P4 is detected by the detection laser S2. Further, the optical pickup 10 is moved to the outer peripheral side until the area that is the target of laser irradiation by each irradiation head 9 becomes an unrecorded 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. And when the processing apparatus 91 of this Embodiment detects the recorded area | region, it is each irradiation head 9 while moving the optical pick-up 10 gradually in a moving direction (from an inner peripheral side toward an outer peripheral side). The recording process for forming the pits P is temporarily stopped, and the optical pickup 10 is moved 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 in the direction by the radial length of the recorded area, recording is started again. For this reason, the processing apparatus 91 according to the present embodiment can form pits at high speed, and can accurately and efficiently form pits over the entire region 33P of the object 33 to be processed. It becomes.

Claims

A rotating unit that rotates a processing target member having a heat mode type recording material layer in which information is recorded by heat generated by irradiation of at least the recording laser beam;
A plurality of irradiations that irradiate recording laser beams to regions that are arranged on a straight line passing through the rotation center of the processing target member rotated by the rotating unit and that have different radial distances from the rotation center of the processing target member. And
A processing device with
The plurality of irradiation portions are arranged at a predetermined interval, and the predetermined interval is a distance from one end portion in the radial direction centered on the rotation center in a predetermined processing target region of the processing target member to the other end portion. The processing apparatus according to claim 1, which is a value divided by the number of irradiation units.
Formed by each of the plurality of irradiation units when a formation pattern corresponding to a predetermined formation target pattern is formed by each of the plurality of irradiation units on the processing target member rotated by the rotation unit. A control unit that controls the irradiation time and irradiation intensity of the recording laser light emitted from each of the plurality of irradiation units so that the size and shape of the formed pattern are the same with each other;
The processing apparatus according to claim 1.
A plurality of irradiation waveform generation units that are provided corresponding to each of the plurality of irradiation units and generate an irradiation waveform;
A plurality of synchronization signal generation units provided corresponding to each of the plurality of irradiation units, and generating a synchronization signal;
With
The plurality of irradiation units are synchronized with a synchronization signal input from the corresponding synchronization signal generation unit, and a recording laser beam having an intensity and an irradiation time according to the irradiation waveform input from the corresponding irradiation waveform generation unit Irradiate
The control unit predetermines a synchronization signal to be output to the reference irradiation unit as one of the plurality of irradiation units as a reference irradiation unit, and outputs the reference synchronization signal to the reference irradiation unit. In addition to controlling the synchronization signal generating unit, the frequency of the synchronization signal increases as the distance increases toward the outer peripheral side according to the distance from the reference irradiation unit, and the synchronization signal increases as the distance increases toward the inner peripheral side. By controlling the synchronization signal generation unit so that the frequency of the signal becomes low, the irradiation time of the recording laser light irradiated from each of the plurality of irradiation units is controlled for each irradiation unit,
The processing apparatus according to claim 3.
An irradiation intensity adjustment unit that adjusts the ratio of the maximum irradiation intensity to the minimum irradiation intensity indicated by the irradiation waveform,
The control unit defines one of the plurality of irradiation units as a reference irradiation unit, 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 unit. The irradiation intensity adjustment unit is controlled so that the ratio of the maximum irradiation intensity 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. By controlling the irradiation intensity of the recording laser light for each irradiation unit,
The processing apparatus according to claim 4.
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 unit is
A light source that emits laser light;
A branching portion 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;
A detection unit for detecting a change in the amount of reflected light of the laser beam for detection by the processing target member;
With
The control unit is configured to move the plurality of irradiation units to a region where the recording region is not detected when a recorded region is detected on the processing target member based on a detection result by the detection unit. Control the moving part,
The processing apparatus according to claim 1.
A condensing unit for condensing the recording laser beam branched by the branching unit and the detection laser beam so as to be irradiated at a predetermined interval in a radial direction of the processing target member; The processing apparatus according to claim 6.
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.
The processing apparatus according to claim 6.
The processing apparatus according to claim 7, wherein the branching unit 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.