JP2006147086A - Optical disk device and optical disk used for the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical disk device capable of efficiently and accurately forming a visible image on a label surface of an optical disk by irradiating with a laser beam without turning the optical disk over. <P>SOLUTION: The optical disk device is provided with: an optical pickup 10 condensing a laser beam L1 on a recording dye film (information recording layer) 52 of a DVD 50, condensing a laser beam L2 on a visible light characteristic change layer (a label layer) 55 and outputting a light receiving signal based on reflected light of the laser beam L1 from the DVD 50; a servo circuit 15 performing focus control and tracking control of the laser beam with which the DVD 50 is irradiated based on the light receiving signal; and a control part 17 controlling the optical pickup 10 so as to emit the laser beam L1 therefrom and to emit the laser beam L2 therefrom based on image data to be printed when the visible image is formed in the DVD 50. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

The present invention relates to an optical disc device and an optical disc used therefor, and more particularly to an optical disc device capable of forming a visible image on an optical disc by irradiating the optical disc with a laser beam and an optical disc used therefor.

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. And an optical disc used therefor are 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,
In addition, it is necessary to perform complicated operations such as printing a sheet with the dedicated printer device and attaching the printed sheet to an optical disk.

Therefore, in recent years, an optical disc apparatus capable of printing on the label surface of the optical disc a visible image (for example, characters indicating a song title or a movie title) for visually recognizing the recorded contents of the optical disc is provided on the label surface of the optical disc. It has come to be.

In such an optical disk device, a laser beam irradiated on the recording surface of the optical disk at the time of reproduction or recording is irradiated onto a predetermined area that becomes the label surface of the optical disk, and a visible image is displayed by changing the color development of the irradiated portion. Some of them are designed (printed). An optical disc for that purpose has also been proposed (see, for example, Patent Document 1).
Japanese Patent Application Laid-Open No. 2004-213796

However, even if the conventional optical disc recording / reproducing apparatus described in Patent Document 1 is used, the user still needs to perform complicated work. That is, when recording information, the user attaches the optical disk to the apparatus so that the recording surface side of the optical disk is irradiated with a laser beam, and when printing a visible image on the label surface of the optical disk, In order to irradiate the laser beam on the surface side, it is necessary to perform a complicated operation of turning the optical disc over and remounting it.

In addition, a conventional optical disk apparatus that performs visible image printing by irradiating a laser beam performs focus control and tracking control of the laser beam based on reflected light from the label surface of the laser beam irradiated to print a visible image. There is a problem that the configuration is complicated because of this.

In addition, in order to perform focus control and tracking control, it is necessary to reflect a part of the laser beam irradiated for printing a visible image on the label surface, so that only a part of the energy of the irradiated laser beam is printed. Therefore, there is a problem that image printing cannot be performed efficiently.

In addition, the conventional optical disc described in Patent Document 1 has position information for performing focus control and tracking control of a laser beam irradiated for printing a visible image, and accurately positioning an irradiation position of the laser beam. In order to obtain the pre-groove, it is necessary to form a pre-groove on the label surface side of the optical disk, which increases the manufacturing cost of the optical disk.

The present invention has been made to solve the above-described problems, and it is not necessary to perform the troublesome work of turning the optical disk upside down when performing label printing of the optical disk, and the optical disk is irradiated with a laser beam. It is an object of the present invention to provide an optical disc apparatus capable of efficiently and accurately forming a visible image on the label surface of the disc and an optical disc used therefor.

In order to achieve the above object, the invention according to claim 1 is characterized in that the information recording layer on which information is reproduced or recorded by irradiation with the first laser beam and the first laser beam are formed. The second laser beam having a different wavelength band is irradiated with a label layer on which a visible image is formed, and the reflectance of the first laser beam provided between the information recording layer and the label layer is second. Reproduction or recording of information and visible by irradiating an optical disc provided with a dichroic reflective film having a higher reflectance than that of the laser beam from the information recording layer side with the first and second laser beams. An optical disc apparatus for forming an image, wherein the first
A first laser diode that emits a 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 diode A second laser diode driver for driving;
An optical system that focuses the laser beam on the information recording layer of the optical disc and a second laser beam on the label layer of the optical disc, and a tracking actuator that drives the optical system in the radial direction of the optical disc, A focus actuator that drives the optical system in the optical axis direction; and a light receiving element that receives a reflected light of the first laser beam from the dichroic reflective film of the optical disc and outputs a received light signal based on the received reflected light. An optical pickup having the optical pickup, and the tracking actuator is driven based on position information of the groove included in the light reception signal to perform tracking control of the laser beam applied to the optical disk, and the optical disk included in the light reception signal Based on the focus information of the irradiated first laser beam, A servo circuit for controlling the focus of a laser beam applied to the optical disk by driving a cas actuator, and driving a first laser diode driver and forming image data of the visible image when forming a visible image on the optical disk And a control unit for driving the second laser diode driver based on the above.

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 optical pickup. At this time, the first irradiated
Since the laser beam is reflected by the dichroic reflecting film, the visible light characteristic changing film is not affected.

Further, a visible image can be formed on the label layer by irradiating the label layer of the optical disc 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.

Further, when forming a visible image, not only the second laser beam is irradiated based on the image data of the visible image to be formed, but also the first laser beam is irradiated. Then, the optical system of the optical pickup is controlled based on the position information of the groove of the optical disk included in the light reception signal based on the reflected light from the dichroic reflection film of the optical disk of the optical disk by the servo circuit. The tracking actuator to be driven is driven and tracking control of the laser beam irradiated onto the optical disc is performed.

Further, a laser beam that is applied to the optical disc by driving a focus actuator that drives the optical system of the optical pickup based on the focus information of the first laser beam applied to the optical disc included in the received light signal by the servo circuit. Focus control is performed. Thus, since the first and second laser beams are condensed by the same optical system, both the first and second laser beams are subjected to tracking control and focus control.

According to the second aspect of the present invention, information is reproduced or recorded by irradiation with the first laser beam, and a visible image 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 a visible image by irradiating the formed optical disc with first and second laser beams from the side of the optical disc where information is reproduced or recorded. The first and second laser beams are emitted, the emitted first and second laser beams are condensed on the optical disc, and the reflected light of the first laser beam from the optical disc is received. An optical pickup that outputs a light reception signal based on the received reflected light, and a laser beam that is irradiated onto the optical disc by operating the optical pickup based on the light reception signal. A servo circuit that performs focusing control and tracking control of Zabimu, in forming a visible image on the optical disk, first from the optical pickup 1
And a control unit for controlling to emit the second laser beam based on the image data of the visible image.

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, a visible image can be formed by irradiating the optical disc with a second laser beam from an optical pickup from the side of the optical disc where information is recorded / reproduced or recorded.

Further, when forming a visible image, not only the second laser beam is irradiated based on the image data of the visible image to be formed, but also the first laser beam is irradiated. Then, focus control and tracking control of the laser beam irradiated to the optical disc by operating the optical pickup based on the light reception signal based on the reflected light from the optical disc of the irradiated first laser beam by the servo circuit. Is done. 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 a third aspect of the present invention, there is provided an information recording layer on which information is reproduced or recorded by irradiating a first laser beam and a second laser having a wavelength band different from that of the first laser beam. The reflectance of the first laser beam provided between the label layer on which a visible image is formed by irradiation of the beam and the information recording layer and the label layer is greater than the reflectance of the second laser beam. An optical disc apparatus for reproducing or recording information and forming a visible image by irradiating an optical disc having a higher dichroic reflective film with the first and second laser beams from the information recording layer side The first and second laser beams are emitted, the emitted first laser beam is condensed on the information recording layer of the optical disc, and the emitted second laser beam is emitted. An optical pickup that collects light on the label layer of the optical disc, receives reflected light from the dichroic reflecting film of the optical disc of the first laser beam, and outputs a received light signal based on the received reflected light; and Focus control and tracking control of the laser beam applied to the optical disc are performed by operating the optical pickup based on the position information of the groove included and the focus information of the first laser beam applied to the optical disc. Servo circuit and control for controlling to emit a first laser beam from the optical pickup and to emit a second laser beam based on image data of the visible image when forming a visible image on the optical disc An optical disc device characterized in that the optical disc apparatus is provided.

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 optical pickup. At this time, the first irradiated
Since the laser beam is reflected by the dichroic reflecting film, the visible light characteristic changing film is not affected.

Further, a visible image can be formed on the label layer by irradiating the label layer of the optical disc 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.

Further, when forming a visible image, not only the second laser beam is irradiated based on the image data of the visible image to be formed, but also the first laser beam is irradiated. Then, focus control and tracking control of the laser beam irradiated to the optical disc by operating the optical pickup based on the light reception signal based on the reflected light from the optical disc of the irradiated first laser beam by the servo circuit. Is done. 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 optical system that focuses the laser beam on the label layer of the optical disc, a tracking actuator that drives the optical system in the radial direction of the optical disc, a focus actuator that drives the optical system in the optical axis direction, and a first actuator Light reception based on the reflected light received from the dichroic reflective film of the optical disk of the laser beam. So that having a light receiving element for outputting a degree.

According to a fifth aspect of the present invention, in the fourth aspect of the invention, the servo circuit drives the tracking actuator based on position information of the groove included in the light reception signal to track the laser beam irradiated on the optical disc. And 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 applied to the optical disc included in the received light signal. ing.

In the invention of claim 6, in the invention of claim 4 or claim 5, the control unit drives the first laser diode driver and forms image data of the visible image when forming a visible image on the optical disc. Based on the above, the second laser diode driver is driven.

According to the seventh aspect of the present invention, there is provided an information recording layer on which information is reproduced or recorded by irradiation with a first laser beam, and a second laser having a wavelength band different from that of the first laser beam. The reflectance of the first laser beam provided between the label layer on which a visible image is formed by irradiation of the beam and the information recording layer and the label layer is greater than the reflectance of the second laser beam. An optical disc having a higher dichroic reflective film, further comprising a transparent intermediate layer, wherein the dichroic reflective film is a film formed by laminating a dye, a dielectric film, or a dielectric 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 690 nm.
800 nm, the information recording layer and the label layer are bonded together via the transparent intermediate layer, and the label layer has a characteristic that its absorbance is maximized at the wavelength of the second laser beam. An optical disc is provided.

According to an eighth aspect of the present invention, there is provided an information recording layer on which information is reproduced or recorded by irradiating a first laser beam and a second laser having a wavelength band different from that of the first laser beam. An optical disc comprising a label layer on which a visible image is formed by irradiation of a beam, further comprising a transparent intermediate layer, wherein the information recording layer has a refractive index of 30% reflectivity for the first laser beam. These values give the above, the transmittance for the second laser beam is 90% or more, and further, 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, and the wavelength band of the second laser beam is 770 nm to 770 nm.
800 nm, the information recording layer and the label layer are bonded together via the transparent intermediate layer, and the label layer has a characteristic that its absorbance is maximized at the wavelength of the second laser beam. An optical disc is provided.

According to the ninth aspect of the present invention, there is provided an information recording layer on which information is reproduced or recorded by irradiating a first laser beam and a second laser having a wavelength band different from that of the first laser beam. An optical disc comprising a label layer on which a visible image is formed by irradiation with a beam, the reflectivity of the first laser beam provided between the information recording layer and the label layer being a second laser The optical disk is further provided with a dichroic reflection film having a higher reflectance than the beam, and the label layer has a characteristic that the absorbance is maximized at the wavelength of the second laser beam.

According to the tenth aspect of the present invention, there is provided an information recording layer on which information is reproduced or recorded by irradiating a first laser beam and a second laser having a wavelength band different from that of the first laser beam. An optical disc including a label layer on which a visible image is formed by irradiation with a beam, wherein the information recording layer has a value such that the refractive index of the first laser beam gives a reflectance of 30% or more. A dichroic reflective film having a transmittance of 90% or more for the second laser beam, and the label layer has a characteristic that the absorbance is maximized at the wavelength of the second laser beam. An optical disc is provided.

According to an eleventh aspect of the present invention, in the ninth or tenth aspect of the present invention, the dichroic reflective film is a dichroic reflective film made of a dye.

According to a twelfth aspect of the present invention, in the ninth or tenth aspect of the present invention, the dichroic reflective film is a dichroic reflective film comprising a dielectric film or a film formed by laminating dielectrics. It is a film.

In the invention of claim 13, in any one of claims 9 to 12, 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 fourteenth aspect of the invention, in the invention according to any one of the ninth to thirteenth aspects, the information recording layer and the label layer are bonded together via the transparent intermediate layer.

As described above, according to the present invention, it is possible to reproduce or record information by irradiating the optical disc with the first laser beam from the optical pickup, and to the optical disc from the optical pickup with the second laser beam. Since an optical disc apparatus capable of forming a visible image, that is, performing label printing by irradiating a laser beam from the side on which information is reproduced or recorded on the optical disc can be realized. It is necessary to carry out complicated work such as preparing a dedicated printer device, attaching a separately printed label sheet to an optical disc on which information is recorded, or turning the optical disc over and mounting it again in the device. Disappear.

According to the present invention, when forming a visible image, that is, performing label printing, not only the second laser beam is irradiated based on the image data of the visible image to be formed, but also the first laser beam. The focus control and tracking control of the laser beam irradiated to the optical disc 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 by the servo circuit Is done. As a result, the first and second laser beams are collected by the same optical pickup.
Since tracking control and focus control are performed for both of the second laser beams, an optical disc apparatus capable of efficiently and accurately forming a visible image on the label surface of the optical disc can be realized.

Further, according to the present invention, information is reproduced or recorded in the information recording layer by irradiating the optical disc with the first laser beam from the information recording layer side, and from the information recording layer side. When the second laser beam is irradiated, the second laser beam passes through the dichroic reflective film and reaches the label layer, and a visible image is formed in the label layer.
This makes it possible to reproduce or record information on the information recording layer and to form a visible image on the label layer, that is, label printing, without requiring the troublesome task of turning the optical disc upside down and mounting it in the apparatus. An optical disc can be realized.

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 a 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 has a characteristic that its absorbance is maximized at the wavelength of the second laser beam, almost all of the energy of the second laser beam irradiated to the label layer changes the color of the irradiated part ( In other words, the image can be formed efficiently without wasting energy. As a result, it is possible to form an image at a higher speed than an optical disc having a conventional label layer. In other words, if the image formation time is the same, image formation with higher resolution can be performed. Also,
Since the second laser beam irradiated to the label layer is not reflected, the reflected light of the second laser beam does not become a control stray light based on the reflected light of the first laser beam, and is stable. Control can be performed.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. First, the configuration of an optical disc targeted by the optical disc apparatus according to the present embodiment will be described, and then the configuration of the optical disc device according to the present embodiment. The operation and the like 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 that enables label printing by irradiating a beam.

The DVD 50 shown in FIG. 1 has a thickness T of 1.2 mm, and also has a substrate 51, a recording dye film 52 as an information recording layer, a color filter (dichroic reflective film) 53, and a visible light characteristic as a label layer. The change layer 55 and the substrate 54 are sequentially stacked. The color filter 53
And the visible light property changing layer 55 is a transparent intermediate layer 56 made of an adhesive or the like for bonding the color filter 53 and the visible light property changing layer 55 together. FIG. 1 shows a DVD 50.
These structures are schematically shown, and the shape, dimensional 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.

  The substrates 51 and 54 are 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.

In the DVD 50 of the present embodiment, the visible light characteristic changing layer 55 serving as a label layer is locally discolored only by being irradiated with light of a predetermined band (for example, infrared light having a wavelength of 780 nm). (Or deformed) material, for example, a polymer film.
As a polymer film, for example, a color change (for example, from white to black, or from transparent to black, such as a photosensitive material or a heat-sensitive material), by applying light or heat. The characteristics of visible light from the substrate 54 at the irradiated position are irradiated with a focused laser beam having a predetermined power or higher, such as a layer of a material (photosensitive layer, heat-sensitive layer, etc.) A layer made of a material that changes. 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.

In the case of a conventional optical disc provided with a visible light characteristic change layer, the visible light characteristic change layer is
Although it has been necessary to configure the material with a property that reflects light of a predetermined band to be irradiated (for example, infrared light having a wavelength of 780 nm) to some extent, the visible light property changing layer 55 of the DVD 50 of this embodiment Since it is made of a material having a maximum absorbance at the wavelength of light in the predetermined band, the light in the predetermined band to be irradiated is almost absorbed. That is, the irradiated light of the predetermined band is hardly reflected, and almost all the energy of the irradiated light of the predetermined band is used as energy for changing (or deforming) the irradiated part. As a result, label printing can be performed efficiently without wasting energy.

In the case of a conventional optical disc having a visible light characteristic change layer, a groove for guiding light in a predetermined band to be irradiated (for example, infrared light having a wavelength of 780 nm) is formed in the visible light characteristic change layer. However, such a groove is not formed in the visible light characteristic changing layer 55. Accordingly, the manufacturing process for forming the groove in the visible light characteristic change layer 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. For example, the recording dye film 52 and the color filter 53 deposited on the substrate 51, and the substrate 54 are used. It is manufactured by adhering the layer on which the visible light characteristic changing layer 55 is deposited on the color filter 53 with an adhesive or the like constituting the transparent intermediate layer 56 with the visible light characteristic changing layer 55 facing the color filter 53 side. Can do. The transparent intermediate layer 56 is preferably transparent.

Further, the thickness from the surface of the optical disk irradiated with the laser beam to the recording surface (information recording layer) is different for CD and DVD, and DVD 50 uses an optical disk device compatible with both CD and DVD. Since the DVD is capable of label printing by irradiating the laser beam on the CD, the thickness from the optical disk surface on the side irradiated with the laser beam to the visible light characteristic change layer 55 is irradiated by the laser beam of the CD. It is formed so as to be approximately equal to the thickness from the surface of the optical disk to the recording surface to the recording surface.

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, and a spindle motor 21.

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;
The optical system 40 for condensing the laser beams L1 and L2 onto the DVD 50 (the recording dye film 52 and the visible light characteristic changing layer 55), the light receiving element 36 that receives the reflected light, and the light reception signal from the light receiving element 36 is amplified. The head amplifier (HA) 12 is provided.

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 forms an image on the visible light characteristic changing layer 55. Adverse effects such as forming an unintended image can be avoided.

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. As shown in FIG. 5, the light is condensed on the visible light characteristic changing layer 55 which is the label surface of the DVD 50 through the 30, the quarter wavelength plate 31 and the objective lens 32.

As described above, since the visible light characteristic change layer 55 has a characteristic of absorbing almost all infrared light, the laser beam L2 applied to the visible light characteristic change layer 55 is hardly reflected. The energy of the laser beam L2 irradiated to the visible light characteristic changing layer 55 is almost entirely used as energy for changing the color of the irradiated part (or deformation).

The laser beam L2 is also emitted when the optical disk mounted on the optical disk apparatus 100 is a CD and the CD is reproduced or recorded. In this case, the irradiated laser beam L2 is separated into three laser beams L2 as described above, and the mounted CD.
Is condensed on the recording surface.

The three laser beams L2 reflected by the recording surface of the mounted CD are again
The light passes through the objective lens 32, the quarter-wave plate 31, and the collimator lens 30, is reflected by the deflection beam splitter 39 a, enters the light receiving element 36 through the cylindrical lens 33. Then, the light receiving element 56 outputs the received signal to the head amplifier 12,
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 thickness from the surface of the optical disk irradiated with the laser beam to the recording surface is CD and DVD.
Therefore, the optical disc apparatus 100 corresponding to both CD and DVD forms a hologram on the objective lens 32 to thereby determine the spot position of the DVD laser beam L1 and the spot position of the CD laser beam L2. Are adjusted in advance to match the recording surfaces of the CD and DVD.

As described above, since the visible light characteristic changing layer 55 of the DVD 50 is provided at a position corresponding to the recording surface of the CD 50, when performing label printing of the DVD 50, the laser beam L2 is emitted from the visible light characteristic changing layer 55. It will be focused on. In order to change the spot position between CD and DVD, two sets of optical pickups are provided, or an optical path changing means such as a hologram for changing the optical path is provided separately from the objective lens 32, or two objectives having different focal lengths are provided. Other methods such as providing a lens may be used.

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 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 central processing unit (CPU) and a read only memory (ROM).
y), a RAM (Random Access Memory), a buffer memory, etc. (all not shown), and the CPU controls each part of the optical disk device 100 according to firmware (program) stored in the ROM. Various processes for playback or recording, and various processes for label printing, and when a CD is loaded, the C
Various processes for reproduction or recording with respect to D are centrally controlled. The RAM is used as a work memory for various processes.

At the time of reproduction, the control unit 17 gives an instruction signal for outputting the reproduction laser beam to the LDD 11a, LPC 14a or the LDD 11b, LPC 14b in order to emit the reproduction laser beam from the optical pickup 10. Then, it is read from the loaded optical disk and F
Various data such as music data demodulated by the EP 13 is transmitted to the PC 110 as the back end, and the data is reproduced by various reproducing means of the PC 100. On the other hand, at the time of recording, recording data to be recorded on the mounted optical disk is transmitted from the PC 110 as the back end and stored in the buffer memory in the control unit 17. Based on the recording data stored in the buffer memory, the control unit 17 outputs the recording laser beam to the LDD 11a, LPC 14a or LDD 11b, LPC 14b in order to emit the recording laser beam from the optical pickup 10. An instruction signal is given, and recording data is recorded on the mounted optical disk.

The recording data includes information recording data such as music data and video data to be recorded on the recording surface of the optical disc, and image data for label printing. This image data is
Data for forming a visible image on the surface of a disk-shaped optical disk, which is converted into polar coordinate data from image bitmap data input to the PC 110 or formed on the label surface of the optical disk generated by the PC 110 This is data in which information indicating the degree of gradation (shading) of each of a plurality of coordinate points on a large number of concentric circles centered on the center point of the optical disk is described.

Next, the label printing operation on the DVD 50 of the optical disc apparatus 100 having such a configuration is performed.
This 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 start label printing on the set DVD 50 is given from the PC 110 to the control unit 17 (step S1). At this time, the image data of the image to be printed is also P.
The control unit 17 supplies the received image data to the control unit 17.
Stored in the buffer memory.

Next, the control unit 17 controls the motor drive circuit 16 so that the spindle motor 21 performs D
The VD 50 is rotated at a predetermined speed (step S2).

Next, the control unit 17 gives an instruction signal to the LDD 11a and the LPC 14a, and irradiates the DVD 50 with the laser beam L1 having a reproduction level power from the optical pickup 10 (step S3).
). At this time, the servo circuit 15 performs the above-described focus control and tracking control based on the light reception signal from the head amplifier 12 that is a signal of the reflected light from the color filter 53 of the DVD 50 of the irradiated laser beam L1.

Next, the control unit 17 gives a movement start instruction to the motor controller 20 based on the image data stored in the buffer memory, and moves the optical pickup 10 to a position where laser irradiation for image formation is performed (step). S4).

When the optical pickup 10 reaches the laser irradiation position based on the image data stored in the buffer memory, the control unit 17 gives an instruction signal to the LDD 11b and the LPC 14b, and the laser corresponding to the image data from the optical pickup 10 The beam L2 is irradiated onto the DVD 50 (step S5). Note that the power of the laser beam L2 at this time is determined in accordance with the degree of gradation (shading) included in the image data.

At this time, in the laser beam L2 irradiated on the visible light characteristic changing layer 55 of the DVD 50, the objective lens 32 is focus-controlled and tracking-controlled by the servo circuit 15 based on the reflected light of the irradiated laser beam L1. Therefore, the image data on the visible light characteristic changing layer 55 is accurately aligned and focused on the coordinate point where the image data is to be formed.

That is, the visible light characteristic changing layer 55 of the DVD 50 is not provided with a groove for focus control and tracking control, and the laser beam L irradiated for image formation is used.
2, the laser beam L <b> 2 is accurately applied to a desired position on the visible light characteristic change layer 55 without performing focus control and tracking control based on the reflected light. Thereby, a desired image can be accurately formed on the label surface of the DVD 50.

Further, at this time, the laser beam L irradiated onto the visible light characteristic changing layer 55 of the DVD 50.
No. 2 is used as energy for discoloring (or deforming) the irradiated portion, so that energy can be efficiently formed without wasting energy. As a result, it is possible to form an image at a higher speed than an optical disc having a conventional visible light characteristic change layer. In other words, if the image formation time is the same, image formation with higher resolution can be performed. Further, since the laser beam L2 is not reflected by the visible light characteristic changing layer 55, the laser beam L2 does not become stray light for control based on the reflected light of the laser beam L1, and stable control can be performed. .

Then, the control unit 17 determines whether or not the image formation processing by the irradiation of the laser beam L2 has been performed on all the image data stored in the buffer memory, that is, whether or not the formation of the image to be formed has been completed. If it is determined that all the images have not been formed yet, the process returns to step S4 to continue image formation.

On the other hand, when it is determined that the formation has been completed, an instruction signal is given to the LDD 11a and LPC 14a to stop the irradiation of the laser beam L1 from the optical pickup 10, and the motor drive circuit 16 is controlled to rotate the DVD 50 by the motor 21. (Step S6
). This completes the label printing operation.

As described above, according to the optical disc apparatus 100 shown in the present embodiment, the DVD 50
On the other hand, it is possible not only to reproduce or record original information but also to form a visible image efficiently and accurately. Further, once the user sets the recording surface of the DVD 50 on the optical disk device 100 so that the recording surface of the DVD 50 faces the optical pickup 10, information is recorded on the recording dye film 52 which is the recording surface of the DVD 50 in the same manner as the conventional device. In addition, a visible image can be formed on the visible light characteristic changing layer 55 that is the label surface. For this reason, the user does not need to prepare a dedicated printer device, and attaches a separately printed label sheet to a DVD on which information is recorded, or turns the DVD 50 over and sets it again for label printing. There is no need to perform such complicated work.

Further, in the DVD 50 described in this embodiment described above, a light source for DVD (630 nm)
Information is reproduced or recorded with a light source of ˜690 nm band, and a light source for CD (770 nm to 800 nm)
Although an example in which label printing is performed with a light source in the nm band is shown, the present invention can be applied to other examples. Specifically, for example, the present invention is also applied to an example in which information is recorded on an optical disk using a 405 nm band laser light source, which is a light source for next-generation DVD, and label printing is performed using a light source for DVD. Is possible.

In the DVD 50 shown in the present embodiment described above, the color filter 53 that is a two-color reflection film is disposed between the recording dye layer 52 that is an information recording layer and the visible light characteristic changing layer 55 that is a label layer. However, 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 reflection film (as described above, the reflectance of the band used for DVD recording is 30% or more, and the band used for CD reproduction) The color filter 53 may be omitted. However, in the optical disc according to the present invention, the recording dye film 52 and the visible light characteristic changing layer 5
5, an intermediate layer for preventing thermal interference is preferably formed.

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. 4 is a flowchart for explaining an operation of the optical disc apparatus shown in FIG. 3.

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 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 50 DVD (optical disk)
51, 54 Substrate 52 Dye recording film (information recording layer)
52a Groove 53 color filter (dichroic reflective film)
55 Visible light property changing layer (label layer)
56 Transparent intermediate layer 100 Optical disk device 110 Personal computer (PC, back end)
L1 laser beam (first laser beam)
L2 laser beam (second laser beam)

Claims (14)

By irradiating an information recording layer on which information is reproduced or recorded by irradiating the first laser beam with a groove formed and a second laser beam having a wavelength band different from that of the first laser beam A label layer on which a visible image is formed, and a dichroic reflecting film provided between the information recording layer and the label layer, wherein the reflectance of the first laser beam is higher than the reflectance of the second laser beam An optical disc apparatus that reproduces or records information and forms a visible image by irradiating the optical disc with the first and second laser beams from the information recording layer side,
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 optical system for condensing the first laser beam on the information recording layer of the optical disc and condensing the second laser beam on a label layer of the optical disc; A tracking actuator that drives the optical system in the radial direction of the optical disc, a focus actuator that drives the optical system in the optical axis direction, and a reflected light from the dichroic reflective film of the optical disc of the first laser beam is received and received. An optical pickup having a light receiving element that outputs a light reception signal based on the reflected light,
The tracking actuator is driven based on position information of the groove included in the light reception signal to perform tracking control of the laser beam irradiated to the optical disk, and the first optical disk irradiated to the optical disk included in the light reception signal is performed. A servo circuit that drives the focus actuator based on the focus information of the laser beam to perform focus control of the laser beam irradiated onto the optical disc;
A controller that drives a first laser diode driver and drives a second laser diode driver based on image data of the visible image when forming a visible image on the optical disc;
An optical disc apparatus comprising: Information is reproduced or recorded by irradiation with the first laser beam, and an optical disk on which a visible image 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 that reproduces or records information and forms a visible image by irradiating the first and second laser beams from the side of the optical disc where information is reproduced or recorded,
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 that outputs a received light signal based on
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;
A control unit that controls to emit a first laser beam from the optical pickup and emit a second laser beam based on image data of the visible image when forming a visible image on the optical disc;
An optical disc apparatus comprising: By irradiating an information recording layer on which information is reproduced or recorded by irradiating the first laser beam with a groove formed and a second laser beam having a wavelength band different from that of the first laser beam A label layer on which a visible image is formed, and a dichroic reflecting film provided between the information recording layer and the label layer, wherein the reflectance of the first laser beam is higher than the reflectance of the second laser beam An optical disc apparatus that reproduces or records information and forms a visible image by irradiating the optical disc with the first and second laser beams from the information recording layer side,
First and second laser beams are emitted, and the emitted first laser beam is condensed on the information recording layer of the optical disc and the emitted second laser beam is condensed on the label layer of the optical disc. An optical pickup that receives reflected light from the dichroic reflecting film of the optical disc of the first laser beam and outputs a received light signal based on the received reflected light;
Focus control of the laser beam applied to the optical disc by operating the optical pickup based on the position information of the groove included in the light reception signal and the focus information of the first laser beam applied to the optical disc; A servo circuit for tracking control;
A control unit that controls to emit a first laser beam from the optical pickup and emit a second laser beam based on image data of the visible image when forming a visible image on 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 optical system 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 optical system in the radial direction of the optical disc;
A focus actuator that drives the optical system in the optical axis direction;
A light receiving element that receives reflected light of the first laser beam from the dichroic reflecting film of the optical disc and outputs a light receiving signal based on the received reflected light;
The optical disc apparatus according to claim 3, wherein The servo circuit drives the tracking actuator based on the position information of the groove included in the light reception signal to perform tracking control of the laser beam irradiated to the optical disk, and controls the optical disk included in the light reception signal. 5. The optical disk apparatus according to claim 4, wherein the focus actuator of the laser beam irradiated to the optical disk is controlled by driving the focus actuator based on focus information of the irradiated first laser beam. The control unit drives a first laser diode driver and drives a second laser diode driver based on image data of the visible image when forming a visible image on the optical disc. Item 6. The optical disk device according to Item 4 or Item 5. By irradiating an information recording layer on which information is reproduced or recorded by irradiating the first laser beam with a groove formed and a second laser beam having a wavelength band different from that of the first laser beam A label layer on which a visible image is formed, and a dichroic reflecting film provided between the information recording layer and the label layer, wherein the reflectance of the first laser beam is higher than the reflectance of the second laser beam An optical disc comprising:
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 information recording layer and the label layer are bonded via the transparent intermediate layer,
The optical disc, wherein the label layer has a characteristic that the absorbance is maximized at the wavelength of the second laser beam. By irradiating an information recording layer on which information is reproduced or recorded by irradiating the first laser beam with a groove formed and a second laser beam having a wavelength band different from that of the first laser beam An optical disc comprising a label layer on which a visible image is formed,
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 information recording layer and the label layer are bonded via the transparent intermediate layer,
The optical disc, wherein the label layer has a characteristic that the absorbance is maximized at the wavelength of the second laser beam. By irradiating an information recording layer on which information is reproduced or recorded by irradiating the first laser beam with a groove formed and a second laser beam having a wavelength band different from that of the first laser beam An optical disc comprising a label layer on which a visible image is formed,
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 has a characteristic that the absorbance is maximized at the wavelength of the second laser beam. By irradiating an information recording layer on which information is reproduced or recorded by irradiating the first laser beam with a groove formed and a second laser beam having a wavelength band different from that of the first laser beam An optical disc comprising a label layer on which a visible image is formed,
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. Consists of
The optical disc, wherein the label layer has a characteristic that the absorbance is maximized at the wavelength of the second laser beam. The optical disk according to claim 9 or 10, wherein the dichroic reflective film is a dichroic reflective film made of a pigment. 11. The dichroic reflective film according to claim 9, wherein the dichroic reflective film is a dichroic reflective film made of a dielectric film or a film formed by laminating dielectrics. optical disk. 13. 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.
An optical disc according to any one of the above. The optical disk according to claim 9, wherein the information recording layer and the label layer are bonded together via the transparent intermediate layer.

Images