JP2009158096A - Optical disk - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical disk which allows stereoscopic visual information to be accurately formed on a label surface by irradiation with a laser beam. <P>SOLUTION: A DVD 50 includes a substrate 51, a recording dye film 52 to be an information recording layer, a color filter (a dichroic reflection film) 53 and a label layer 54 sequentially laminated. Here, a transparent inner layer 55 composed of an adhesive for sticking the color filter 53 and the label layer 54 to each other, or the like, is provided between the color filter 53 and the label layer 54. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an optical disc, and more particularly, to an optical disc in which three-dimensional visible information can be formed on a label surface of an optical disc by irradiating a laser beam.

Conventionally, by irradiating a laser beam onto an optical disk such as a CD (Compact Disk) or a DVD (Digital Versatile Disk), music information or video information recorded on the optical disk is recorded. There has been provided an optical disc apparatus for reproducing information and recording such information on the optical disc.

  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-described problem, and an object of the present invention is to provide an optical disc capable of accurately forming three-dimensional visible information on the label surface of the optical disc by irradiating a laser beam. To do.

  According to the first aspect of the present invention, an information recording layer on which information is reproduced or recorded by being irradiated with the first laser beam, and a second laser beam having a wavelength band different from that of the first laser beam are irradiated. A label layer on which visible information is formed, and two colors which are provided between the information recording layer and the label layer and have a higher reflectance for the first laser beam than the reflectance for the second laser beam. An optical disk comprising a reflective reflective film, further comprising a transparent intermediate layer, wherein the dichroic reflective film is a two-color film composed of a dye, a dielectric film, or a film formed by laminating dielectrics The wavelength band of the first laser beam is 630 nm to 690 nm, the wavelength band of the second laser beam is 770 nm to 800 nm, and the label layer includes a monomer, A resin substrate made of a photo-composition changing resin composed of a ligomer, a photopolymerization initiator, and an additive, wherein the information recording layer and the label layer are bonded together via the transparent intermediate layer. An optical disc is provided.

  According to the second aspect of the present invention, an information recording layer on which information is reproduced or recorded by irradiation of the first laser beam and a second laser beam having a wavelength band different from that of the first laser beam are irradiated. And a label layer on which visible information is formed, further comprising a transparent intermediate layer, wherein the information recording layer has a refractive index of 30% or more for the first laser beam. A dichroic reflective film composed of a film formed by laminating a dye, a dielectric film, or a dielectric, the transmittance of the second laser beam being 90% or more. The wavelength band of the first laser beam is 630 nm to 690 nm, the wavelength band of the second laser beam is 770 nm to 800 nm, and the label layer includes a monomer, A resin substrate made of a photo-composition changing resin composed of a ligomer, a photopolymerization initiator, and an additive, wherein the information recording layer and the label layer are bonded together via the transparent intermediate layer. An optical disc is provided.

  According to the third aspect of the present invention, an information recording layer on which information is reproduced or recorded by irradiation of the first laser beam and a second laser beam having a wavelength band different from that of the first laser beam are irradiated. An optical disc including a label layer on which visible information is formed, and the reflectivity for the first laser beam provided between the information recording layer and the label layer is reflected for the second laser beam. The optical disk is further provided with a dichroic reflective film having a higher rate than the above-mentioned ratio, and the label layer is a resin substrate made of a photo composition change resin.

According to a fourth aspect of the invention, an information recording layer on which information is reproduced or recorded by irradiation of the first laser beam and a second laser beam having a wavelength band different from that of the first laser beam are irradiated. The information recording layer has a value such that the refractive index with respect to the first laser beam gives a reflectance of 30% or more, and the second information layer has a label layer on which visible information is formed. The optical disk is characterized in that it comprises a dichroic reflective film having a transmittance of 90% or more for the laser beam, and the label layer is a resin substrate made of a photo composition change resin.

  The invention of claim 5 is characterized in that, in the invention of claim 3 or claim 4, the photo composition change resin is composed of a monomer, an oligomer, a photopolymerization initiator, and an additive.

  The invention of claim 6 is characterized in that, in the invention of any one of claims 3 to 5, the dichroic reflective film is a dichroic reflective film made of a dye.

  According to a seventh aspect of the present invention, in the invention according to any one of the third to fifth aspects, the dichroic reflective film is a dielectric film or a film formed by laminating dielectrics. It is a chromatic reflection film.

  In the invention of claim 8, in any one of claims 3 to 7, the wavelength band of the first laser beam is 630 nm to 690 nm, and the wavelength band of the second laser beam is 770 nm to 800 nm. It is characterized by being.

  According to a ninth aspect of the present invention, in any one of the third to eighth aspects, the information recording layer and the label layer are bonded together via the transparent intermediate layer.

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

  According to the present invention, the first laser beam is irradiated from the information recording layer side of the optical disc to reproduce or record information in the information recording layer, and the second laser beam from the information recording layer side. , The second laser beam passes through the dichroic reflective film and reaches the label layer, and a visible image can be formed in the label layer. That is, it is possible to realize an optical disc that can reproduce or record information on the information recording layer and form a visible image on the label layer by laser beam irradiation.

  Further, the dichroic reflective film is made of a material having a reflectivity for the first laser beam higher than that of the second laser beam, or a refractive index for the first laser beam of 30% or more. Since the value is such that the transmittance of the second laser beam is 90% or more, the first laser beam irradiated from the information recording layer side can be used efficiently. The recording accuracy of information on the optical disc can be improved.

  Further, by providing the dichroic reflective film, it is possible to avoid an unintended influence on the label layer by the laser beam irradiated for reproducing or recording information on the information recording layer. As a result, the present invention is considered to have advantages over the thinning of the optical disc and the lamination of a plurality of information recording layers in one optical disc.

  Further, since the label layer is a resin substrate made of a photo-composition changing resin composed of a monomer, an oligomer, a photopolymerization initiator, and an additive, the portion irradiated by the second laser beam irradiated to the label layer Causes a change in composition, which changes the visible light characteristics, so that three-dimensional visible information can be formed in the label layer.

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.

  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 the information recorded on the DVD 50, the laser beam is controlled (focus control) so that the laser beam is focused on the groove 52a, and the laser beam is moved along the groove 52a. Is controlled (tracking control). At this time, the reflected light 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 a dichroic reflective film made of a dielectric film, but may be a cyanine dye NK-67 (manufactured by Nippon Photosensitivity Laboratories) having a structure represented by the following chemical formula (Formula 1). You may be comprised with the pigment | dye.

  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. Therefore, the color filter 53 can exhibit high reflectance in the vicinity of a wavelength of 650 nm by optimizing the film thickness and reducing the film thickness. 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. The layers constituting the color filter 53 have such a value that the refractive index of a band used for DVD recording gives a reflectance of 30% or more in the band, and is used for reproducing a CD. It is preferable that the band is constituted by a layer having a transmittance of 90% or more.

  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. Accordingly, the manufacturing process for forming the groove in the label layer 54 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. In addition, the rotational drive system of the spindle motor 21 includes a system in which the DVD 50 is rotationally driven at a constant angular velocity (CAV system: Constant Angular Velocity), and a system in which the DVD 50 is rotationally driven so as to have 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 includes a laser diode 37a that emits a laser beam L1, which is red light having a wavelength of 660 nm, used for reproducing or recording a DVD, and for reproducing or recording a CD and for label printing. A laser diode 37b that emits a laser beam L2 that is infrared light having a wavelength of 780 nm, a laser diode driver (LDD) 11a that drives the laser diode 37a, and a laser diode driver (LDD) that drives the laser diode 37b. 11b, the 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), the light receiving element 36 for receiving the reflected light, and the light receiving signal from the light receiving element 36 is amplified. Position of the head amplifier (HA) 12 and the laser diode 37b The laser diode is moved in the axial direction (LD) and a moving part 41.

  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 separated into a main beam and two sub beams (preceding beam and trailing beam) by the diffraction grating 38a, and these three laser beams L1 are polarized beam splitters 39a, 39b, As shown in FIG. 5, the light is condensed on a recording dye film 52 which is a recording surface of the DVD 50 through the collimator lens 30, the quarter wavelength plate 31 and the objective lens 32.

  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 transmitted again through the objective lens 32, the quarter wavelength plate 31, the collimator lens 30, and the polarization beam splitter 39b, and reflected by the deflection beam splitter 39a. Thus, the light enters 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 this received light signal that has undergone predetermined modulation and supplies it to the control unit 17.

  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 and supplied to the LPC circuits 14a and 14b shown in FIG. Then, the LPC circuits 14a and 14b control the LDDs 11a and 11b so that laser powers having values that match the target values of the optimum laser power indicated by the control unit 17 are emitted from the laser diodes 37a and 37b, respectively. 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 is held by a focus actuator 34 and a tracking actuator 35, and can move 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 generates an FE signal and a TE signal based on the amplified light reception signal supplied from the head amplifier 12 and applies them to the focus actuator 34 and the tracking actuator 35 to perform focus control and tracking control.

  Here, the above-described three laser beams L1 emitted from the optical pickup 10 and irradiated onto the DVD are one of the main beam spot centers when the center of one groove 52a (see FIG. 1) of the DVD 50 is located. The sub-beam spot is in the positional relationship such that the spot on the groove 52a is on the inner surface and the other beam spot is on 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. Then, 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 the main beam is targeted even if the DVD 50 rotates eccentrically. It is possible to accurately trace the center of the groove 52a (tracking control). This tracking control may be performed by a phase difference method (one beam tracking method) in addition to the above-described three beam method.

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

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. The focus of the beam can be accurately adjusted to the target position on the DVD 50 (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 move the laser beam irradiation position of the optical pickup 10 to various positions of the DVD 50. Can do.

The control unit 17 includes a CPU (Central Processing Unit), a ROM (Read Only Memory), and a RAM (Random Access Memory) (not shown), and the CPU is an optical disc device according to firmware (program) stored in the ROM. 100 units are controlled to centrally control various processes for reproduction or recording on the DVD 50 and various processes for label printing. 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. Then, various data such as music data read from the recording dye film 52 of the DVD 50 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. Then, the control unit 17 gives an irradiation instruction signal to the LDD 11 and the LPC circuit 14 in order to emit the laser beam L1 of the recording level from the optical pickup 10 based on the information recording data stored in the buffer memory 22, and Information is recorded on the recording dye film 52. 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, slice data indicating each cross-sectional shape obtained by slicing the three-dimensional image at a predetermined slice pitch (30 μm to 70 μm) in the thickness direction of the label layer 54 for each cross-sectional shape A plurality of slice data created for each cross-sectional shape is stored 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. In order to achieve this, an irradiation instruction signal is given to the LDD 11b and the LPC circuit 14b, whereby the portion of the label layer 54 irradiated with the laser beam L2 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, the DVD 50 is set in the optical disc apparatus 100, and when the user operates the PC 110, an instruction to form visible information on the set DVD 50 is given 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 refers to the label layer 54 having the slice pitch (30 μm to 70 μm) obtained by slicing a stereoscopic image formed when creating a plurality of slice data stored in the buffer memory 22. It is a cross section sliced in the thickness direction.

  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. An irradiation instruction signal is given to the LDD 11b and the LPC 14b while the optical pickup 10 is moved to a position where laser irradiation for forming visible information is performed by giving a movement start instruction, and the laser beam L2 is irradiated from the optical pickup 10 onto the label layer 54. (Step S5). Note that the power of the laser beam L2 at this time is determined according to the degree of gradation (shading) included in the slice data to be referenced. As a result, the outermost cross-sectional shape of the three-dimensional image 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 to the next inner cross section of the label layer 54. Continue forming the cross-sectional shape.

  On the other hand, when it is determined that the formation has been completed (Yes in step S8), the irradiation instruction signal to the LDD 11a and 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, the label layer 54 is not only reproduced or recorded on the DVD 50 but also irradiated with the laser beam L2. 3D visual information can be accurately formed.

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

Further, in the DVD 50 shown in the present embodiment described above, the color filter 53 that is a dichroic reflection film is disposed between the recording dye layer 52 that is an information recording layer and the label layer 54. It 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). 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.

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 (9)

Visible information is formed by irradiating an information recording layer on which information is reproduced or recorded by being irradiated with the first laser beam, and a second laser beam having a wavelength band different from that of the first laser beam. Optical disc comprising: a label layer that is formed, and a dichroic reflection film that is provided between the information recording layer and the label layer and has a higher reflectance for the first laser beam than the reflectance for the second laser beam Because
A transparent intermediate layer,
The dichroic reflective film is a dichroic reflective film composed of a dye, a dielectric film, or a film formed by laminating a dielectric,
The wavelength band of the first laser beam is 630 nm to 690 nm,
The wavelength band of the second laser beam is 770 nm to 800 nm,
The label layer is a resin substrate made of a photocomposition change resin composed of a monomer, an oligomer, a photopolymerization initiator, and an additive,
The optical disc, wherein the information recording layer and the label layer are bonded together via the transparent intermediate layer. Visible information is formed by irradiating an information recording layer on which information is reproduced or recorded by being irradiated with the first laser beam, and a second laser beam having a wavelength band different from that of the first laser beam. An optical disc comprising a label layer to be provided,
A transparent intermediate layer,
The information recording layer has such a value that the refractive index for the first laser beam gives a reflectance of 30% or more, the transmittance for the second laser beam is 90% or more, and further, a dye, dielectric Consisting of a dichroic reflective film consisting of a body film or a film formed by laminating dielectrics,
The wavelength band of the first laser beam is 630 nm to 690 nm,
The wavelength band of the second laser beam is 770 nm to 800 nm,
The label layer is a resin substrate made of a photocomposition change resin composed of a monomer, an oligomer, a photopolymerization initiator, and an additive,
The optical disc, wherein the information recording layer and the label layer are bonded together via the transparent intermediate layer. Visible information is formed by irradiating an information recording layer on which information is reproduced or recorded by being irradiated with the first laser beam, and a second laser beam having a wavelength band different from that of the first laser beam. An optical disc comprising a label layer to be provided,
A dichroic reflective film provided between the information recording layer and the label layer and having a reflectivity for the first laser beam higher than that for the second laser beam;
The optical disc, wherein the label layer is a resin substrate made of a photo composition change resin. Visible information is formed by irradiating an information recording layer on which information is reproduced or recorded by being irradiated with the first laser beam, and a second laser beam having a wavelength band different from that of the first laser beam. An optical disc comprising a label layer to be provided,
The information recording layer has a value such that the refractive index for the first laser beam gives a reflectance of 30% or more, and the transmittance for the second laser beam is 90% or more. Consisting of
The optical disc, wherein the label layer is a resin substrate made of a photo composition change resin. The optical disc according to claim 3 or 4, wherein the photo-composition changing resin is composed of a monomer, an oligomer, a photopolymerization initiator, and an additive.   6. The optical disk according to claim 3, wherein the dichroic reflective film is a dichroic reflective film made of a pigment.   The dichroic reflective film is a dichroic reflective film made of a dielectric film or a film formed by laminating dielectrics. The optical disc described in 1.   8. The optical disk according to claim 3, wherein the wavelength band of the first laser beam is 630 nm to 690 nm, and the wavelength band of the second laser beam is 770 nm to 800 nm. .   The optical disc according to any one of claims 3 to 8, wherein the information recording layer and the label layer are bonded together via the transparent intermediate layer.

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