JP4321439B2 - Optical disk device - Google Patents

Description

The present invention relates to an optical disc equipment, in particular, an optical disc equipment that can be performed in the formation of three-dimensional visual information on the label surface of the optical disk by irradiating a laser beam
About the.

Conventionally, CD (Compact Disk) and DVD (Digital Versatile)
By irradiating a laser beam to an optical disk such as a disk (digital versatile disk), information such as music information and video information recorded on the optical disk is reproduced, or such information is recorded on the optical disk. An optical disc device is provided.

In addition, since it is convenient for the optical disc on which the information is recorded to be recognized by the appearance, the user can use a dedicated printer device to indicate characters or the like indicating the content recorded on the optical disc (for example, , Song titles, movie titles, etc.) are printed on a circular sheet, and this sheet is pasted on the surface opposite to the recording surface of the optical disc (hereinafter referred to as the label surface).

However, in this method, the user needs to prepare a dedicated printer device, and needs to perform complicated operations such as printing a sheet with the dedicated printer device and pasting the printed sheet on an optical disk. .

Therefore, in recent years, the recorded content of the optical disc can be visualized by irradiating a predetermined area that becomes the label surface of the optical disc with a laser beam irradiated on the recording surface of the optical disc at the time of reproduction or recording, and changing the color development etc. of the irradiated portion. Optical discs and optical disc apparatuses capable of forming (printing) visible information (for example, characters indicating song titles, movie titles, etc.) for recognizing automatically have come to be provided.

Such an optical disc includes a visible information recording layer formed on a substrate and on which visible information is recorded by light irradiated from a label surface side opposite to the substrate side, and the visible information recording There is an optical information recording medium characterized in that the layer is formed in a region outside the circumference having a radius of ½ of the radius of the substrate (see, for example, Patent Document 1).

Further, an optical recording medium having an optical recording layer on one main surface of the support substrate, and having a reversible recording layer containing the reversible thermosensitive color-forming composition on the other main surface of the support substrate, There is also an optical recording medium characterized in that the reversible thermosensitive color-developing composition contains a light-heat conversion material that generates heat by absorbing infrared rays (see, for example, Patent Document 2).
JP 2004-213816 A JP 2004-188826 A

However, the visible information that can be formed on the label surface of the optical disk using a conventional optical disk and optical disk device is limited to a flat one, and three-dimensional visible information such as a three-dimensional image cannot be formed. It was.

In addition, the conventional optical information recording medium described in Patent Document 1 can reduce the warpage of the disk due to recording visible information on the label surface, but it does not form three-dimensional visible information on the label surface. could not.

In addition, the conventional optical recording medium described in Patent Document 2 can record visible information such as images and titles on the label surface in a rewritable manner, but the visible information to be recorded is limited to a flat one. The three-dimensional visible information could not be recorded.

The present invention has been made to solve the above problems, to provide an optical disk equipment capable of accurately forming a three-dimensional visual information on the label surface of the optical disk by irradiating a laser beam Objective.

In order to achieve the above object, the invention according to claim 1 includes an information recording layer in which pits or grooves are formed and information is reproduced or recorded by being irradiated with the first laser beam, A label layer on which visible information is formed by irradiation with a second laser beam having a wavelength band different from that of the laser beam, and reflection of the first laser beam provided between the information recording layer and the label layer. An optical disc apparatus for reproducing or recording information and forming visible information with respect to an optical disc provided with a dichroic reflective film having a higher rate than the reflectance for the second laser beam, A first laser diode that emits a laser beam; a first laser diode driver that drives the first laser diode; and a second laser that emits a second laser beam. Second driving the diode, a second laser diode
A laser diode driver, an objective lens for condensing the first laser beam on the information recording layer and condensing a second laser beam on the label layer, and driving the objective lens in the radial direction of the optical disc A tracking actuator, a focus actuator that drives the objective lens in the optical axis direction, and a light receiving element that receives a reflected light of the first laser beam from the dichroic reflecting film and outputs a received light signal based on the received reflected light And an optical pickup having a laser diode moving unit that moves the position of the second laser diode in the optical axis direction, and driving the tracking actuator based on positional information of the pit or groove included in the light reception signal. In addition to performing tracking control of the laser beam applied to the optical disc A servo circuit for controlling the focus of the laser beam applied to the optical disc by driving the focus actuator based on the focus information of the first laser beam in the information recording layer included in the light reception signal, and the label layer A storage unit that stores slice data indicating each cross-sectional shape when the stereoscopic image is sliced at a predetermined pitch in the thickness direction of the label layer when the visible information to be formed is a stereoscopic image; When forming the stereoscopic image on the label layer, the first laser diode driver is driven and the second laser diode driver is driven based on the slice data for each sectional shape stored in the storage unit. And the focal position of the second laser beam in the label layer is moved forward in the thickness direction of the label layer. To provide an optical disk apparatus characterized by comprising a controller for controlling the laser diode moving unit to move at a predetermined pitch.

According to this configuration, information can be reproduced or recorded by irradiating the information recording layer of the optical disc with the first laser beam from the first laser diode of the optical pickup through the objective lens. . At this time, the irradiated first laser beam is reflected by the dichroic reflecting film of the optical disc, and thus does not affect the label layer of the optical disc.

Further, the second laser beam is irradiated from the second laser diode of the optical pickup to the label layer from the information recording layer side through the objective lens to form visible information on the label layer. Can do. At this time, the irradiated second laser beam passes through the dichroic reflective film and reaches the label layer.

When forming a stereoscopic image as visible information on the label layer, the second laser beam is generated based on slice data of each cross-sectional shape for each predetermined pitch of the stereoscopic image to be formed stored in the storage unit. Irradiation is performed, whereby a cross-sectional shape of the stereoscopic image is formed in the label layer. Further, the laser diode moving unit illuminates the position of the second laser diode so that the focal position of the irradiated second laser beam on the label layer moves at the predetermined pitch in the thickness direction of the label layer. Since it is controlled to move in the axial direction, the cross-sectional shape of the stereoscopic image for each predetermined pitch is formed and laminated at the predetermined pitch in the label layer.

At this time, not only the second laser beam is irradiated based on the slice data, but also the first laser beam is irradiated. Then, the first irradiated by the servo circuit
A tracking actuator for driving the objective lens is driven based on position information of a pit or groove of the information recording layer included in a light reception signal based on reflected light from the dichroic reflecting film of the laser beam of the laser beam to irradiate the optical disc Tracking control of the laser beam to be performed is performed.

In addition, the servo circuit drives the focus actuator that drives the objective lens based on the focus information of the first laser beam in the information recording layer included in the light reception signal, and the focus of the laser beam irradiated on the optical disc Control is performed. As a result, the first and second laser beams are condensed by the same objective lens.
Tracking control and focus control are performed for both of the second laser beams.

According to the second aspect of the present invention, information is reproduced or recorded by being irradiated with the first laser beam, and visible information is obtained by being irradiated with the second laser beam having a wavelength band different from that of the first laser beam. An optical disc apparatus that performs information reproduction or recording and formation of visible information on an optical disc to be formed, emits first and second laser beams, and emits first and second laser beams. Is collected on the optical disk, the reflected light of the first laser beam from the optical disk is received, a light reception signal based on the received reflected light is output, and the focal position of the second laser beam on the optical disk is further emitted. An optical pickup having a focal position moving means for moving in the axial direction, and the optical disc is irradiated by operating the optical pickup based on the received light signal. That a servo circuit that performs focusing control and tracking control of the laser beam, when the visible information to be formed on the record Beru layer is three-dimensional image, when the stereoscopic image is sliced at a predetermined pitch in the direction of the thickness of the label layer A storage unit that stores slice data indicating each cross-sectional shape for each cross-sectional shape, and a first laser beam that is emitted from the optical pickup and stored in the storage unit when the stereoscopic image is formed on the optical disc. The second laser beam is controlled to be emitted based on the slice data for each of the cross-sectional shapes, and the focal position of the second laser beam on the optical disc is the predetermined pitch in the thickness direction of the optical disc. An optical disc apparatus comprising: a control unit that controls the focal position moving means to move at Subjected to.

According to this configuration, information can be reproduced or recorded by irradiating the optical disk with the first laser beam from the optical pickup. Further, visible information can be formed by irradiating the optical disc with a second laser beam from the optical pickup.

When forming a stereoscopic image as visible information on the optical disc, the second laser beam is irradiated based on slice data of each cross-sectional shape for each predetermined pitch of the stereoscopic image to be formed stored in the storage unit. Thereby, a cross-sectional shape of the stereoscopic image is formed on the optical disc. Further, since the focal position moving means is controlled so that the focal position of the second laser beam to be irradiated on the label layer moves in the thickness direction of the label layer at the predetermined pitch, A cross-sectional shape for each predetermined pitch is formed and stacked at the predetermined pitch in the label layer.

At this time, not only the second laser beam is irradiated based on the slice data, but also the first laser beam is irradiated. Then, the first irradiated by the servo circuit
The optical pickup is operated based on a light reception signal based on the reflected light of the laser beam from the optical disc, thereby performing focus control and tracking control of the laser beam applied to the optical disc. Thereby, since the first and second laser beams are condensed by the same optical pickup, both the first and second laser beams are subjected to tracking control and focus control.

According to the third aspect of the present invention, there is provided an information recording layer in which pits or grooves are formed and information is reproduced or recorded by being irradiated with the first laser beam, and has a wavelength band different from that of the first laser beam. A label layer in which visible information is formed by irradiation of the second laser beam, and a reflectance of the first laser beam provided between the information recording layer and the label layer is about the second laser beam. An optical disc apparatus for reproducing or recording information and forming visible information with respect to an optical disc provided with a dichroic reflecting film having a higher reflectance than the first and second laser beams, and emitting first and second laser beams. The emitted first laser beam is condensed on the information recording layer, and the emitted second laser beam is condensed on the label layer, and the dichroism of the first laser beam is collected. An optical pickup having a focal position moving means for receiving reflected light from the projecting film, outputting a received light signal based on the received reflected light, and further moving a focal position of the second laser beam in the label layer in the optical axis direction And tracking of the laser beam irradiated on the optical disc by operating the optical pickup based on the position information of the pit or groove included in the light reception signal and the focus information of the first laser beam in the information recording layer When each of the servo circuit that performs control and focus control and the visible information formed on the label layer is a stereoscopic image, each sectional shape when the stereoscopic image is sliced at a predetermined pitch in the thickness direction of the label layer is shown. A storage unit that stores slice data for each cross-sectional shape, and the light beam when the stereoscopic image is formed on the label layer. Control is performed so that the first laser beam is emitted from the backup and the second laser beam is emitted based on the slice data for each cross-sectional shape stored in the storage unit, and the second laser beam is further emitted. There is provided an optical disc apparatus comprising: a control unit that controls the focal position moving means so that the focal position of the optical disc moves at the predetermined pitch in the thickness direction of the optical disc.

According to this configuration, it is possible to reproduce or record information by irradiating the information recording layer of the optical disc with the first laser beam from the optical pickup. At this time, the irradiated first laser beam is reflected by the dichroic reflecting film of the optical disc, and thus does not affect the label layer of the optical disc.

Further, visible information can be formed on the label layer by irradiating the label layer with a second laser beam from the optical pickup from the information recording layer side. At this time,
The irradiated second laser beam passes through the dichroic reflective film and reaches the label layer.

When forming a stereoscopic image as visible information on the label layer, the second laser beam is generated based on slice data of each cross-sectional shape for each predetermined pitch of the stereoscopic image to be formed stored in the storage unit. Irradiation is performed, whereby a cross-sectional shape of the stereoscopic image is formed in the label layer. Further, the focal position of the irradiated second laser beam in the label layer is controlled so as to move at the predetermined pitch in the thickness direction of the label layer, so that the cross section of the stereoscopic image at the predetermined pitch. A shape is formed and laminated at the predetermined pitch in the label layer.

At this time, not only the second laser beam is irradiated based on the slice data, but also the first laser beam is irradiated. Then, the first irradiated by the servo circuit
Of the laser beam irradiated to the optical disc by operating the optical pickup based on the position information of the pits or grooves of the information recording layer included in the received light signal based on the reflected light from the dichroic reflecting film of the laser beam Tracking control is performed.

The servo circuit controls the focus of the laser beam irradiated on the optical disk by operating the optical pickup based on the focus information of the first laser beam in the information recording layer included in the light reception signal. Thereby, since the first and second laser beams are condensed by the same optical pickup, both the first and second laser beams are subjected to tracking control and focus control.

In the invention of claim 4, in the invention of claim 3, the optical pickup comprises: a first laser diode that emits a first laser beam; a first laser diode driver that drives the first laser diode; A second laser diode that emits a second laser beam; a second laser diode driver that drives the second laser diode; and a second laser diode that focuses the first laser beam on the information recording layer of the optical disc and a second laser diode. An objective lens that focuses the laser beam on the label layer of the optical disc, a tracking actuator that drives the objective lens in the radial direction of the optical disc, a focus actuator that drives the objective lens in the optical axis direction, and a first actuator Light reception based on the reflected light received from the dichroic reflective film of the laser beam. A light receiving element for outputting a No., as the focal position moving means, and to have a laser diode moving unit for moving the position of the second laser diode in the optical axis direction.

According to a fifth aspect of the invention, in the fourth aspect of the invention, the servo circuit drives the tracking actuator based on positional information of the pit or groove included in the light reception signal to irradiate the optical disc. Tracking control is performed, and the focus actuator is driven based on the focus information of the first laser beam in the information recording layer included in the light reception signal to perform focus control of the laser beam irradiated on the optical disc. I have to.

According to a sixth aspect of the invention, in the fourth or fifth aspect of the invention, the control unit drives the first laser diode driver and uses the slice data in forming the stereoscopic image on the label layer. Based on the second laser diode driver, and
The laser diode moving unit is controlled so that the focal position of the second laser beam in the label layer is moved at the predetermined pitch in the thickness direction of the label layer.

In the optical disc and the optical disc apparatus to which the present invention is applied, “visible information”
This means information that can be read visually, such as two-dimensionally or three-dimensionally configured characters, symbols, images such as illustrations and photographs, and geometric patterns.

As described above, according to the present invention, information can be reproduced or recorded by irradiating the optical disc with the first laser beam from the optical pickup, and the optical disc can be reproduced from the optical pickup. Thus, an optical disc apparatus capable of forming three-dimensional visible information by irradiating two laser beams can be realized.

Further, according to the present invention, when forming stereoscopic visible information on an optical disc, that is, a stereoscopic image, the second laser is based on slice data of each cross-sectional shape for each predetermined pitch of the stereoscopic image to be formed. By operating the optical pickup based on the received light signal based on the reflected light from the optical disc of the first laser beam irradiated not only with the beam but also with the first laser beam irradiated with the servo circuit Since focus control and tracking control of the laser beam applied to the optical disc are performed, the first and second laser beams are condensed by the same optical pickup, and therefore both the first and second laser beams are collected. Tracking control and focus control are performed, and a stereoscopic image can be accurately formed on the label surface of the optical disc.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. First, the configuration of the optical disc of the present embodiment will be described, and then three-dimensional visible information is formed on the optical disc for the optical disc. The configuration and operation of the optical disc apparatus according to the present embodiment that can be used will be described.

FIG. 1 is a side sectional view showing the structure of an optical disk assumed in this embodiment. Here, as an optical disc, an optical disc apparatus that performs reproduction and / or recording of a DVD accompanied by a reproduction and / or recording function of a CD can be used to reproduce and / or record DVD information, and a laser for the CD. Assume a DVD capable of forming three-dimensional visible information on a label surface by irradiation with a beam.

The DVD 50 shown in FIG. 1 has a thickness T of 1.2 mm, and a substrate 51, a recording dye film 52 serving as an information recording layer, a color filter (dichroic reflective film) 53, and a label layer 54 are sequentially arranged. It is configured by stacking. A transparent intermediate layer 55 made of an adhesive or the like for bonding the color filter 53 and the label layer 54 is present between the color filter 53 and the label layer 54. FIG. 1 schematically shows the structure of the DVD 50, and the shape, dimension ratio, etc. of each layer are not as shown in this figure.

Among these layers, a groove 52a is spirally formed on the recording dye film 52, and when recording information on the DVD 50, control is performed so that the laser beam is focused on the groove 52a. (Focus control) and control (tracking control) so that the laser beam is irradiated along the groove 52a, and a pit corresponding to the recording data length is formed on the groove 52a.

Similarly, when reproducing information recorded on the DVD 50, the groove 52 is also reproduced.
The laser beam is controlled (focus control) so as to be focused on a, and the laser beam is controlled to be irradiated (tracking control) along the groove 52a.
At this time, the reflected signal of the laser beam reflected from the DVD 50 is demodulated, and the recorded information is reproduced.

In the case of a read-only optical disk, no guide groove like the groove 52a is formed, and instead, a laser beam is focused along a pit which is reproduction information formed on the recording surface. Thus, tracking control and focus control are performed.

  The substrate 51 is made of, for example, polycarbonate resin.

The color filter 53 is composed of a dichroic reflective film formed of a dielectric film such as Zns, SiO2, or SiN or a laminated film thereof. The color filter 53 is preferably formed of a laminated film because the desired dichroism can be made larger than that of a single layer film.

The color filter 53 is not limited to the dichroic reflective film made of a dielectric film, but the following chemical formula
) May be composed of a dye such as cyanine dye NK-67 (manufactured by Nippon Photosensitivity Laboratories).

FIG. 2 shows the absorbance and refractive index of the cyanine dye as the optical characteristics of the cyanine dye as described above.

Referring to FIG. 2, the cyanine dye as described above has a maximum absorbance in the vicinity of a wavelength of 550 nm. And in the area | region of 650 nm vicinity which the said absorbance begins to fall, the refractive index has shown the maximum value. The maximum value of the refractive index of this cyanine dye is about 3.0. Accordingly, the color filter 53 is optimized for the film thickness and is made thin, so that the wavelength 650 is reduced.
A high reflectance can be exhibited in the vicinity of nm. In addition, since the cyanine dye hardly absorbs light in the vicinity of 780 nm, which is the wavelength of light used when reproducing information in a CD player, the color filter 53 exhibits high transmittance.

In the present embodiment, the layer constituting the color filter 53 has at least a band used for DVD recording (630 nm to 690 nm band) and a band used for CD reproduction (770 nm to 800 nm band). It is constituted by a layer having a higher reflectance. Note that the layers constituting the color filter 53 have a refractive index of a band used for DVD recording of 30 in the band.
It is preferable that the layer has a value that gives a reflectance of at least%, and is configured by a layer that has a transmittance of 90% or more in a band used for CD reproduction.

The label layer 54 is a disc-shaped material whose composition changes locally only in the irradiated area when irradiated with light of a predetermined band of a predetermined power or higher (for example, infrared light having a wavelength of 780 nm). The material is, for example, a photo composition change resin composed of a monomer, an oligomer, a photopolymerization initiator, and various additives (stabilizer, filler, pigment, etc.).

Monomers are organic materials that polymerize to form large molecules that form plastics. An oligomer is a material in which several monomers are reacted in advance and is polymerized in the same manner as the monomer to form large molecules to form a plastic.

Since monomers and oligomers do not easily cause a polymerization reaction, a photopolymerization initiator is added to start the reaction. The photopolymerization initiator absorbs light and is activated (excited) to cause a reaction such as a cleavage reaction, hydrogen abstraction, or electron transfer.

This reaction generates a substance that initiates the reaction, such as radical molecules and hydrogen ions. The generated radical molecules, hydrogen ions, and the like attack the oligomer and monomer molecules to cause a composition change such as polymerization.

And the visible light characteristic of the part irradiated with light changes with this composition change. As the visible light characteristic mentioned here, hue, lightness, and saturation, light absorption characteristic, reflectance, transmittance, light scattering, and the like of a visually recognized color can be considered.

Further, in the case of a conventional optical disc having a label layer that changes visible light characteristics by irradiation with light of a predetermined band (for example, infrared light having a wavelength of 780 nm), the label layer has an irradiation with the predetermined band. Grooves for guiding light need to be formed, but it is not necessary to form such grooves in the label layer 54. Therefore, the label layer 5
Thus, the manufacturing process for forming the groove in 4 and the mold used in the process are not required, so that the manufacturing cost of the DVD 50 is reduced as compared with the conventional one.

As long as the DVD 50 is manufactured so as to be provided with each layer as described above, the manufacturing method does not matter, but for example, a recording dye film 52 and a color filter 53 deposited on a substrate 51, and a photo composition The label layer 54, which is a resin substrate made of a change resin, can be manufactured by pasting together the color filter 53 side and the label layer 54 with an adhesive or the like constituting the transparent intermediate layer 55. The transparent intermediate layer 55 is preferably transparent.

Next, an optical disk apparatus capable of performing label printing on the above-described DVD 50 will be described. FIG. 3 is a block diagram showing a configuration of the optical disc apparatus according to the present embodiment. The optical disk apparatus shown in FIG. 3 is an optical disk apparatus that performs reproduction and / or recording of a DVD with a CD reproduction and / or recording function.

As shown in FIG. 3, the optical disc apparatus 100 is connected to a personal computer (PC) 110 as a back end, and includes an optical pickup 10, a front end processor (FEP) 13, and laser power control (LPC) circuits 14a and 14b. A servo circuit 15, a motor drive circuit 16, a control unit 17, a stepping motor 18, a driver 19, a motor controller 20, a spindle motor 21, and a buffer memory 22.

The spindle motor 21 is a motor for rotationally driving the DVD 50 that is a target for recording and reproducing data, and the number of rotations is controlled by the motor drive circuit 16. The motor drive circuit 16 is supplied with an instruction signal from the control unit 17 and a pulse signal having a frequency corresponding to the number of revolutions of the spindle motor 21 fed back from the spindle motor 21 or a sensor provided in the spindle motor 21. The motor drive circuit 16 controls the rotation of the spindle motor 21 based on these supplied signals. The spindle motor 21 is rotationally driven by a method in which the DVD 50 is rotationally driven at a constant angular velocity (CAV method: Constant A).
ngular velocity) or a method of rotating the DVD 50 to achieve a constant recording linear velocity (
CLV method: Constant Linear Velocity), any of which may be used.

The optical pickup 10 is a unit that irradiates the DVD 50 that is rotationally driven by the spindle motor 21 with a laser beam.

FIG. 4 shows the configuration of the optical pickup 10. As shown in FIG. 4, the optical pickup 10
Laser beam L1 which is red light having a wavelength of 660 nm used for DVD reproduction or recording
A laser diode 37a that emits a laser beam L2 that is infrared light having a wavelength of 780 nm and is used for CD reproduction or recording and label printing.
7b and a laser diode driver (LDD) 11a for driving the laser diode 37a
A laser diode driver (LDD) 11b for driving the laser diode 37b;
An optical system 40 for condensing the laser beams L1 and L2 onto the DVD 50 (the recording dye film 52 and the label layer 54), a light receiving element 36 that receives reflected light, and a head amplifier that amplifies a light reception signal from the light receiving element 36. (HA) 12 and a laser diode (LD) moving unit 41 that moves the position of the laser diode 37b in the optical axis direction.

The LDD 11a drives the laser diode 37a according to the instruction signal from the control unit 17 and the control signal from the LPC circuit 14a shown in FIG. 3, and the LDD 11b has the instruction signal from the control unit 17 and the control signal from the LPC circuit 14b. Accordingly, the laser diode 37b is driven.

When a drive current is supplied from the LDD 11a, the laser diode 37a emits a laser beam L1 having an intensity corresponding to the drive current. The laser beam L1 emitted from the laser diode 53a is transmitted through the diffraction grating 38a to the main beam and two sub beams (preceding beam,
These three laser beams L1 are separated into polarization beam splitters 39a.
39b, the collimator lens 30, the quarter-wave plate 31, and the objective lens 32, as shown in FIG. 5, the light is condensed on the recording dye film 52 which is the recording surface of the DVD 50.

Since the laser beam L1 is reflected by the color filter 53 of the DVD 50, the laser beam L1 irradiated for reproducing or recording information on the recording dye film 52 is not intended for image formation on the label layer 54. It is possible to avoid adverse effects such as forming an image.

The three laser beams L1 reflected by the color filter 53 of the DVD 50 are again
Objective lens 32, quarter-wave plate 31, collimator lens 30, polarization beam splitter 39
b is transmitted, reflected by the deflection beam splitter 39a, and incident on the light receiving element 36 through the cylindrical lens 33.

The light receiving element 56 outputs the received signal to the head amplifier 12, and the received light signal is amplified by the head amplifier 12 and supplied to the FEP 13 and the servo circuit 15 shown in FIG. The FEP 13 demodulates the received light signal that has been subjected to the predetermined modulation to control the control unit 1.
7 is supplied.

Further, the servo circuit 15 relates to the position information of the groove 52a used for tracking control and the focus of the laser beam L1 focused on the recording dye film 52 used for focus control, which are included in the received light signal. Information (focus information) will be supplied. Details of the tracking control and focus control will be described later.

On the other hand, when a drive current is supplied from the LDD 11b, the laser diode 37b emits a laser beam L2 having an intensity corresponding to the drive current. The laser beam L2 emitted from the laser diode 53b is separated into a main beam and two sub beams (preceding beam and succeeding beam) by the diffraction grating 38b. These three laser beams L2 are polarized beam splitter 39b, collimator lens. 30, the quarter-wave plate 31, and the objective lens 32, as shown in FIG.

The focal position of the laser beam L2 in the label layer 54 can be moved in the thickness direction of the label layer 54 by the LD moving unit 41 moving the position of the laser diode 37b in the optical axis direction. As described above, the portion of the label layer 54 where the main beam of the laser beam L2 is condensed undergoes a composition change and the visible light characteristics change. In FIG. 5, a white portion in the label layer 54 indicates a portion in which the visible light characteristic is changed due to the composition change caused by the irradiation of the irradiated laser beam L2.

Further, the optical pickup 10 has two front monitor diodes (not shown), and when the laser diodes 37a and 37b emit laser beams, a current is supplied to each front monitor diode that has received the emitted light. Each current is generated as shown in FIG.
It is supplied to the PC circuits 14a and 14b. The LPC circuit 14a, 1
4D is an LDD 11a so that laser power of a value that matches the target value of the optimum laser power indicated by the control unit 17 is emitted from the laser diodes 37a and 37b.
, 11b. The laser power control by the LPC circuits 14a and 14b performed here uses a current value supplied from the front monitor diode, and feedback is performed so that a laser beam having a target intensity is emitted from the laser diodes 37a and 37b. Control.

The objective lens 32 includes a focus actuator 34 and a tracking actuator 3.
5 and is movable in the optical axis direction of the laser beams L1 and L2 and the radial direction of the DVD 50. Each of the focus actuator 34 and the tracking actuator 35 moves the objective lens 32 in the optical axis direction and the radial direction in accordance with a focus error (FE) signal and a tracking error (TE) signal supplied from the servo circuit 15.

The servo circuit 15 performs F based on the amplified light reception signal supplied from the head amplifier 12.
The E signal and the TE signal are generated and given to the focus actuator 34 and the tracking actuator 35, thereby performing focus control and tracking control.

Here, in the above-described three laser beams L1 emitted from the optical pickup 10 and irradiated onto the DVD, the spot center of the main beam is one groove 52a of the DVD 50 (see FIG. 1).
When the spot of one sub beam is located on the inner surface of the groove 52a,
The other sub-beam spot is in such a positional relationship as to be applied to the outer surface of the groove 52a.

Therefore, the servo circuit 15 calculates the difference in the intensity of the reflected light of the two sub beams detected by the light receiving element 36 using the light receiving signal given from the head amplifier 12, so that the main beam becomes the target groove. It is possible to know how much the inner side / outside side is displaced from the center of 52a, that is, the amount of tracking error. The servo circuit 15
Generates a TE signal for reducing the tracking error amount to zero, and controls the tracking actuator 35 with the TE signal, so that even if the DVD 50 rotates eccentrically, the main beam is placed at the center of the target groove 52a. It can be traced accurately (tracking control). Note that this tracking control is not limited to the above-described three-beam method, but a phase difference method (1
The beam tracking method may be used.

Further, as shown in FIG. 6, the light receiving element 36 actually has four detection areas a and b.
, C and d, and the main beam of the laser beam L1 imaged on the light receiving element 36 is
The cylindrical lens 33 becomes a vertical ellipse A when the objective lens 32 is close to the DVD 50, becomes a horizontal ellipse B when it is far away, and becomes a circle C when it is in focus.

For this reason, the received light intensity of the four areas a, b, c, and d is calculated by an arithmetic expression of (a + c) − (b + d), and the objective lens 32 is in focus with respect to the DVD 50 from the obtained calculation result. It is possible to know how much is shifted to the near / far side, that is, the focus error amount. Then, the servo circuit 15 generates an FE signal for setting the focus error amount to a predetermined value, and controls the tracking actuator 35 with the FE signal. Focus on the beam DVD5
It can be accurately adjusted to the target position on 0 (focus control).

Returning to FIG. 3, the stepping motor 18 is a motor for moving the optical pickup 10 in the radial direction of the set DVD 50. The motor driver 19 rotationally drives the stepping motor 18 by an amount corresponding to the pulse signal supplied from the motor controller 20. The motor controller 20 generates a pulse signal corresponding 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 17, and the motor driver 19. Output to. That is, the stepping motor 18 moves the optical pickup 10 in the radial direction of the DVD 50, and the spindle motor 21.
Rotates the DVD 50 to change the laser beam irradiation position of the optical pickup 10 to D.
It can be moved to various positions on the VD 50.

The control unit 17 includes a CPU (Central Processing Unit), a ROM (Read
Only memory) and RAM (Random Access Memory), and the CPU controls each part of the optical disk device 100 according to firmware (program) stored in the ROM, and performs various processes for reproduction or recording on the DVD 50, In addition, various processes for label printing are centrally controlled. The RAM is used as a work memory for various processes.

At the time of information reproduction, the control unit 17 gives an irradiation instruction signal to the LDD 11a and the LPC circuit 14a in order to emit a reproduction level laser beam L1 from the laser diode 37a.
The reproduction level refers to the level of irradiation power at which reflected light necessary for focus control and tracking control by the servo circuit 15 described above can be obtained, and recording is performed on the recording dye film 52 of the DVD 50 with this reproduction level laser beam L1. The recorded information (pits) can be read, but information recording on the recording dye film 52 cannot be performed. And DVD50
Various data such as music data read out from the recording dye film 52 and demodulated by the FEP 13 is transmitted to the PC 110 as the back end, and the data is reproduced by various reproducing means of the PC 100.

At the time of information recording, information recording data such as music data and video data to be recorded on the DVD 50 is transmitted from the PC 110 as the back end and stored in the buffer memory 22. Based on the information recording data stored in the buffer memory 22, the control unit 17 performs LDD to emit a laser beam L 1 at a recording level from the optical pickup 10.
11 and the LPC circuit 14 are given irradiation instruction signals, and information is recorded on the recording dye film 52 of the DVD 50. This recording level refers to the level of irradiation power for writing information (pits) on the recording dye film 52.

Further, at the time of forming visible information, visible information data is transmitted from the back-end PC 110 and stored in the buffer memory 22. The visible information data is data indicating the shape of the visible information formed on the label layer 54 of the optical disc. When the visible information is a stereoscopic image, the visible information data is created on a three-dimensional CAD (Computer Aided Design). From the three-dimensional data indicating the three-dimensional shape of the three-dimensional image, the three-dimensional image is converted into a predetermined slice pitch (in the thickness direction of the label layer 54).
Slice data indicating each cross-sectional shape sliced at 30 μm to 70 μm is created for each cross-sectional shape, and a plurality of slice data for each cross-sectional shape is accumulated in the buffer memory 22. The slice data is obtained by converting the bitmap data indicating each cross-sectional shape of the stereoscopic image into data in the polar coordinate format by the PC 110, and a plurality of concentric circles centered on the central point of the DVD 50. This is data in which information indicating the degree of gradation (shading) of each point is described.

Then, the control unit 17 emits a laser beam L2 having a power necessary for changing the composition of the light composition change resin constituting the label layer 54 from the laser diode 37b based on the plurality of slice data stored in the buffer memory 22. LDD11b and LPC to make
An irradiation instruction signal is given to the circuit 14 b, whereby the portion of the label layer 54 irradiated with the laser beam L 2 undergoes a composition change, and visible information is formed in the label layer 54.

Next, the formation operation of the three-dimensional visible information on the label layer 54 of the DVD 50 of the optical disc apparatus 100 having such a configuration will be described with reference to the flowchart shown in FIG.

First, when the DVD 50 is set in the optical disc apparatus 100 and the user operates the PC 110, a visible information forming instruction to the set DVD 50 is sent from the PC 110 to the control unit 17.
(Step S1). At this time, the three-dimensional visible information formed on the label layer 54, that is, the above-described plurality of slice data of the three-dimensional image to be formed is transmitted from the PC 110 to the buffer memory 22 and stored.

Next, the control unit 17 gives a rotation instruction signal to the motor drive circuit 16 and rotates the DVD 50 at a predetermined speed by the spindle motor 21 (step S2).

Then, the control unit 17 gives an irradiation instruction signal to the LDD 11a and the LPC circuit 14a, and irradiates the DVD 50 with the laser beam L1 at the reproduction level from the laser diode 37a (step S3). Thereafter, focus control and tracking control by the servo circuit 15 described above are performed based on a light reception signal from the head amplifier 12 which is a signal of reflected light from the label surface 59 of the irradiated laser beam L1.

Next, the control unit 17 initializes the focal position of the laser beam L2 in the thickness direction of the label layer 54 (step S4). That is, a movement instruction signal is given to the LD moving unit 41 so that the focal position of the laser beam L2 is on the outermost cross section in the label layer 54, thereby moving the position of the laser diode 37b. Here, the cross section in the label layer 54 is the buffer memory 22.
Is a cross-section obtained by slicing the label layer 54 in the thickness direction at the slice pitch (30 μm to 70 μm) obtained by slicing a three-dimensional image to be formed when creating a plurality of slice data stored in FIG.

Then, the control unit 17 refers to the slice data indicating the outermost cross-sectional shape in the label layer 54 among the plurality of slice data stored in the buffer memory 22, and determines the motor controller 20 based on the slice data. While moving the optical pickup 10 to a position where laser movement for forming visible information is performed by giving a movement start instruction, the LDD 11b
Then, an irradiation instruction signal is given to the LPC 14b to irradiate the label layer 54 with the laser beam L2 from the optical pickup 10 (step S5). Note that the power of the laser beam L2 at this time is determined in accordance with the gradation (darkness) included in the slice data to be referenced. This
The outermost cross-sectional shape of the three-dimensional image label layer 54 formed on the label layer 54 is formed on the outermost cross-section of the label layer 54.

Next, the control unit 17 gives a movement instruction signal to the LD moving unit 41 to move the position of the laser diode 37b so that the focal position of the laser beam L2 moves to the inside of the label layer 54 by the slice pitch ( Step S6).

Then, the control unit 17 refers to the slice data indicating the inner cross-sectional shape next to the cross-sectional shape indicated by the slice data referred to immediately before the slice data stored in the buffer memory 22, and the slice data Based on the above, while giving the movement start instruction to the motor controller 20 and moving the optical pickup 10 to the position where the laser irradiation for forming visible information is performed, the irradiation instruction signal is given to the LDD 11b and LPC 14b, and the laser beam is emitted from the optical pickup 10. The label layer 54 is irradiated with L2 (step S7). Note that the power of the laser beam L2 at this time is determined in accordance with the gradation (darkness) included in the slice data to be referenced. Accordingly, the next inner cross-sectional shape of the three-dimensional image formed on the label layer 54 in the next inner cross-section of the label layer 54 is formed.

Next, the control unit 17 determines whether or not the cross-sectional shape forming process by irradiation with the laser beam L2 has been performed on all of the plurality of slice data accumulated in the buffer memory 22, that is, all cross-sectional shapes to be formed. Is determined (step S8), and when it is determined that the formation has not been completed yet (No in step S8), the process returns to step S6,
The formation of the cross-sectional shape for the next inner cross-section of the label layer 54 is continued.

On the other hand, when it is determined that the formation has been completed (Yes in step S8), the LDD 11a
The irradiation instruction signal to the LPC circuit 14a is stopped, the irradiation of the laser beam L1 from the laser diode 37a is stopped, and the motor drive circuit 16 is controlled to stop the rotation of the DVD 50 by the motor 21 (step S9). Thus, the three-dimensional visible information forming operation on the label layer 54 is completed.

In this way, the cross-sectional shape of the stereoscopic image corresponding to the cross-section is formed in order from the cross-section on the outer side of the label layer 54 in the cross-section for each slice pitch of the label layer 54, and these cross-sectional shapes are laminated. A three-dimensional image is formed on the label layer 54.

Further, the laser beam L2 applied to the label layer 54 is separately controlled in focus and tracking by the servo circuit 15 based on the reflected light of the irradiated laser beam L1, and therefore the label layer 54 At 54, the coordinate point (coordinate point indicating the irradiation position of the laser beam L2) indicated by the slice data referred to at that time is accurately aligned and focused.

Therefore, although the label layer 54 of the DVD 50 is not provided with a groove or the like for focus control and tracking control, the laser beam L2 is accurately irradiated to a desired position of the label layer 54. . As a result, even if surface deflection in the radial direction or thickness direction occurs when the DVD 50 rotates, a desired stereoscopic image can be accurately formed on the label layer 54 of the DVD 50.

As described above, according to the DVD 50 and the optical disc apparatus 100 shown in the present embodiment, not only the original information is reproduced or recorded on the DVD 50, but also the laser beam L
By irradiating 2, three-dimensional visible information can be accurately formed on the label layer 54.

The optical disk shown in the present embodiment described above is a DVD, and the optical disk apparatus is D.
Although the optical disk apparatus is for reproducing or recording VD, the present invention can be applied to other optical disks and optical disk apparatuses. Specifically, for example, CD and next-generation DVD
The present invention is also applicable to an example in which three-dimensional visible information is formed on an optical disc that is reproduced / recorded using a 405 nm band laser beam.

Further, in the DVD 50 shown in the present embodiment described above, the recording dye layer 5 which is an information recording layer.
The color filter 53, which is a two-color reflection film, is disposed between the label layer 54 and the label layer 54, but the optical disc of the present invention is not limited to such a configuration. For example, the recording dye layer 52 is a layer that can form a dichroic reflective film (as described above, the reflectance of the band used for DVD recording is 30% or more, and is used for CD reproduction). Layer with a transmittance of 90% or more)
In the case where the color filter 53 is configured, the color filter 53 may be omitted. However, in the optical disc according to the present invention, it is preferable that an intermediate layer for preventing thermal interference is formed between the recording dye film 52 and the label layer 54.

The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

It is a sectional side view which shows the structure of DVD which is one Embodiment of the optical disk of this invention. It is a figure which shows the light absorbency and refractive index of the cyanine dye which can be made into the material of a color filter in DVD shown in FIG. It is a block diagram which shows the structure of the optical disk apparatus of one Embodiment of this invention. It is a figure which shows the structure of the optical pick-up shown in FIG. It is a figure for demonstrating the optical path of the laser beam radiate | emitted from the optical pick-up shown in FIG. It is a figure which shows the structure of the light receiving element shown in FIG. FIG. 4 is a flowchart for explaining a stereoscopic visible information forming operation of the optical disc apparatus shown in FIG. 3. FIG.

Explanation of symbols

10 Optical pickup 11a Laser diode driver (LDD, first laser diode driver)
11b Laser diode driver (LDD, second laser diode driver)
12 Head Amplifier (HA)
13 Front-end processor (FEP)
14a, 14b Laser power control (LPC) circuit 15 Servo circuit 16 Motor drive circuit 17 Control unit 18 Stepping motor 19 Driver 20 Motor controller 21 Spindle motor 22 Buffer memory (storage unit)
30 Collimator lens 31 1/4 wavelength plate 32 Objective lens 33 Cylindrical lens 34 Focus actuator 35 Tracking actuator 36 Light receiving element 37a Laser diode (first laser diode)
37b Laser diode (second laser diode)
38a, 38b Diffraction gratings 39a, 39b Polarizing beam splitter 40 Optical system 41 Laser diode (LD) moving unit (focal position moving means)
50 DVD (optical disc)
51 Substrate 52 Dye recording film (information recording layer)
52a groove 53 color filter (dichroic reflective film)
54 Label layer 55 Transparent intermediate layer 100 Optical disc device 110 Personal computer (PC, back end)
L1 laser beam (first laser beam)
L2 laser beam (second laser beam)

Claims (6)

An information recording layer in which pits or grooves are formed and information is reproduced or recorded by irradiation with the first laser beam, and a second laser beam with a wavelength band different from that of the first laser beam is irradiated In this manner, the reflectance of the first laser beam provided between the information recording layer and the label layer, on which visible information is formed, is higher than the reflectance of the second laser beam. An optical disk device for reproducing or recording information and forming visible information with respect to an optical disk provided with a chromatic reflection film,
A first laser diode that emits a first laser beam, a first laser diode driver that drives the first laser diode, a second laser diode that emits a second laser beam, and a second laser A second laser diode driver for driving a diode; an objective lens for condensing the first laser beam on the information recording layer and condensing the second laser beam on the label layer; and the objective lens for the optical disc. A tracking actuator that drives the objective lens in the optical axis direction, a focus actuator that drives the objective lens in the optical axis direction, and receives light reflected from the dichroic reflective film of the first laser beam and receives light based on the received reflected light A laser diode that moves the position of the light receiving element that outputs a signal and the second laser diode in the optical axis direction. An optical pickup having a moving portion,
The tracking actuator is driven based on position information of the pit or groove included in the light reception signal to perform tracking control of a laser beam irradiated to the optical disc, and the information recording layer included in the information recording layer includes the light reception signal. A servo circuit that drives the focus actuator based on focus information of one laser beam to perform focus control of the laser beam irradiated onto the optical disc;
When the visible information formed on the label layer is a stereoscopic image, slice data indicating each sectional shape when the stereoscopic image is sliced at a predetermined pitch in the thickness direction of the label layer is stored for each sectional shape. A storage unit;
When forming the stereoscopic image on the label layer, the first laser diode driver is driven and the second laser diode driver is driven based on slice data for each cross-sectional shape stored in the storage unit. And a control unit for controlling the laser diode moving unit so that a focal position of the second laser beam in the label layer moves at the predetermined pitch in the thickness direction of the label layer;
An optical disc apparatus comprising: Information is reproduced or recorded by irradiation with the first laser beam, and an optical disc on which visible information is formed by irradiation with a second laser beam having a wavelength band different from that of the first laser beam. An optical disc apparatus for reproducing or recording information and forming visible information,
First and second laser beams are emitted, the emitted first and second laser beams are condensed on the optical disc, and reflected light from the optical disc is received and received by the first laser beam. An optical pickup having a focal position moving means for moving a focal position of the second laser beam on the optical disc in the direction of the optical axis;
A servo circuit that performs focus control and tracking control of a laser beam irradiated on the optical disc by operating the optical pickup based on the light reception signal;
When visible information forming Les Beru layer is three-dimensional image, stores slice data showing each cross-sectional shape when the stereoscopic image is sliced at a predetermined pitch in the direction of the thickness of the label layer for each cross-sectional shape A storage unit;
When forming the three-dimensional image on the optical disc, the first laser beam is emitted from the optical pickup, and the second laser beam is generated based on slice data for each sectional shape stored in the storage unit. A control unit for controlling the focal position moving means so that the focal position of the second laser beam on the optical disc moves at the predetermined pitch in the thickness direction of the optical disc;
An optical disc apparatus comprising: An information recording layer in which pits or grooves are formed and information is reproduced or recorded by irradiation with the first laser beam, and a second laser beam with a wavelength band different from that of the first laser beam is irradiated In this manner, the reflectance of the first laser beam provided between the information recording layer and the label layer, on which visible information is formed, is higher than the reflectance of the second laser beam. An optical disk device for reproducing or recording information and forming visible information with respect to an optical disk provided with a chromatic reflection film,
The first and second laser beams are emitted, the emitted first laser beam is condensed on the information recording layer, and the emitted second laser beam is condensed on the label layer,
Receiving the reflected light of the laser beam from the dichroic reflecting film, outputting a received light signal based on the received reflected light, and further moving the focal position of the second laser beam in the label layer in the optical axis direction. An optical pickup having a focal position moving means;
Tracking control of a laser beam irradiated on the optical disc by operating the optical pickup based on position information of the pit or groove included in the light reception signal and focus information of the first laser beam in the information recording layer; A servo circuit for focus control;
When the visible information formed on the label layer is a stereoscopic image, slice data indicating each sectional shape when the stereoscopic image is sliced at a predetermined pitch in the thickness direction of the label layer is stored for each sectional shape. A storage unit;
When forming the three-dimensional image on the label layer, the first laser beam is emitted from the optical pickup, and the second laser beam based on slice data for each cross-sectional shape stored in the storage unit A control unit for controlling the focal position moving means so that the focal position of the second laser beam on the optical disc moves at the predetermined pitch in the thickness direction of the optical disc;
An optical disc apparatus comprising: The optical pickup is
A first laser diode emitting a first laser beam;
A first laser diode driver for driving the first laser diode;
A second laser diode emitting a second laser beam;
A second laser diode driver for driving the second laser diode;
An objective lens for condensing the first laser beam on the information recording layer of the optical disc and condensing the second laser beam on the label layer of the optical disc;
A tracking actuator for driving the objective lens in the radial direction of the optical disc;
A focus actuator for driving the objective lens in the optical axis direction;
A light receiving element that receives reflected light from the dichroic reflecting film of the first laser beam and outputs a light receiving signal based on the received reflected light; and
As the focal position moving means, a laser diode moving unit that moves the position of the second laser diode in the optical axis direction;
The optical disc apparatus according to claim 3, wherein The servo circuit drives the tracking actuator based on position information of the pit or groove included in the light reception signal to perform tracking control of a laser beam irradiated on the optical disc, and includes the light signal included in the light reception signal. 5. The optical disk apparatus according to claim 4, wherein the focus actuator of the laser beam applied to the optical disk is controlled by driving the focus actuator based on focus information of the first laser beam in the information recording layer. The control unit drives a first laser diode driver and drives a second laser diode driver based on the slice data when forming the stereoscopic image on the label layer, and further drives a second laser diode driver. 6. The optical disk device according to claim 4, wherein the laser diode moving unit is controlled so that a focal position of a beam in the label layer is moved at the predetermined pitch in a thickness direction of the label layer. .

Images