JP4020161B2 - Optical disk recording device - Google Patents

Description

  The present invention relates to an optical disc recording apparatus capable of forming a visible image on an optical disc.

2. Description of the Related Art Optical disk recording apparatuses that record music data or the like on an optical disk such as a CD-R (Compact Disc-Recordable) or a CD-RW (Compact Disc-Rewritable) are widely used. An optical disk recording apparatus records data by irradiating an optical disk with laser light to form pits corresponding to the data length.
By the way, when data is recorded on many optical disks, it is convenient if the recorded contents of each optical disk can be discriminated visually. Therefore, an optical disk recording apparatus capable of forming a visible image such as characters in a disk area (unrecorded area) where data was not recorded is being provided. This optical disk recording apparatus forms a visible image such as letters and numbers by irradiating a laser beam onto an unrecorded area and changing the color of the irradiated part.

  However, conventional optical disk recording apparatuses cannot form a visible image because an unrecorded area is not specified unless all data is recorded. For this reason, when a plurality of pieces of data are additionally recorded in several times (TAO method, etc.), a visible image can be formed even though there is a request to form a visible image in the middle of data recording. There wasn't.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide an optical disc recording apparatus capable of forming a visible image at any time regardless of the progress of data recording.

In order to solve the above-described problems, the configuration of the optical disk recording apparatus according to the present invention is a light beam for irradiating a laser beam to an optical disk having a disk-shaped recording layer that has a property of being discolored by heat or light. Visible image forming means for forming a visible image by irradiating a laser beam from the optical pickup to the pickup and the recording layer, and partially changing the color of the recording layer in order from the inner circumference side of the disc, A first visible image is sequentially formed from a position on the inner circumference side of the disk by a predetermined distance from a predetermined end position in any of a plurality of divided areas obtained by dividing the recording layer by radiation from the center of the optical disk. formed, after forming the first visible image, the first divided area visible image is not formed in the plurality of divided regions, whether rough And having a visible image forming means for forming a second visible image in order from the predetermined distance on the inner peripheral side of the disk position than the end point position determined fit.

  According to such a configuration of the optical disk recording apparatus, a disk-shaped recording layer having a property of being discolored by heat or light is irradiated with laser light from the optical pickup, and recording is performed in order from the inner circumference side of the disk. A visible image can be formed by partially discoloring the layer. Further, when a plurality of visible images are formed, the inner circumference of the disc is a predetermined distance from the predetermined end point position in each of the plurality of divided regions obtained by dividing the recording layer by radiation from the center of the optical disc. A visible image can be formed from the side position. Therefore, for example, a visible image can be formed even at a stage where data recording is not completely completed (close processing) and an unrecorded area of data is not fixed.

Here, have a position detecting means for the irradiation position of the laser beam in the optical disc to detect which of the plurality of divided regions, the visible image forming means, the outer periphery of the irradiation position of the laser beam from the inner peripheral side It is good also as a structure which forms a visible image by irradiating a laser beam to the division area containing the irradiation position detected by the said position detection means when it moves to the side . With such a configuration, even when the optical disc is reset in the optical disc recording apparatus, it is possible to always detect in which divided region the laser beam irradiation position is located. Therefore, there is no problem that a visible image is erroneously formed in a non-divided divided area.
Further, the optical disk is an optical disk having a recording layer in which a guide groove is spirally formed, and laser light is irradiated from the optical pickup along the guide groove to form pits in order from the inner peripheral side of the disk. Thus, it may be configured to have data recording means for recording data.

Here, in the case where the optical disk is an optical disk having a recording layer in which a guide groove is formed in a spiral shape, when forming a visible image, the optical pick-up is performed along the guide groove on the recording layer. A visible image may be formed by irradiating a laser beam and partially discoloring the recording layer in order from the inner circumference side of the disk.
Alternatively, the optical disc further includes a driving unit that rotationally drives the optical disc, and a feed unit that sequentially moves the optical pickup in the outer peripheral direction of the optical disc, and the visible image forming unit is the optical disc that is rotationally driven by the driving unit. The recording layer is irradiated with a laser beam from the optical pickup, and the laser beam irradiation position in the recording layer is moved from the inner circumference side of the disc to the outer circumference in order using the feed means. This is a preferred embodiment.

  ADVANTAGE OF THE INVENTION According to this invention, the optical disk recording device which can form a visible image irrespective of the condition of data recording can be provided. For example, it is possible to form a visible image on an optical disc that is scheduled to be additionally recorded in the future.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
A: First Embodiment An optical disc recording apparatus according to the present embodiment has a function of recording original data such as music data on an optical disc and a function of forming a visible image such as characters.
First, in the optical disc recording apparatus according to the present embodiment, the configuration of an optical disc that performs data recording and visible image formation will be described, and then the configuration of the optical disc recording apparatus according to the present embodiment will be described.

(Configuration of optical disc)
FIG. 1 is a side sectional view of an optical disc 200 on which an optical disc recording apparatus according to this embodiment performs data recording and visible image formation. In this embodiment, a CD-R disc is assumed.
As shown in FIG. 1, the optical disc 200 has a protective layer 201, a recording layer 202, a reflective layer 203, and a protective layer 204, and has a laminated structure. FIG. 1 schematically shows the structure of the optical disc 200, and the dimensional ratios of the layers are not as shown in this figure.

Of these layers, a spiral groove (guide groove) 202g is formed on the recording layer 202. When information is recorded on the optical disc 200, laser light is irradiated along the groove 202g. (On-groove recording). That is, when recording information on the optical disc 200, as schematically shown in FIG. 2, the laser beam is focused and controlled on the groove 202g, and the laser beam is irradiated along the groove 202g. When a laser beam with a certain intensity (amount of heat) is irradiated, pits 202p corresponding to the recording data length are formed on the groove 202g, and data recording is performed. FIG. 3 is a diagram schematically showing how pits 202p are formed as a result of laser light irradiation along the groove 202g.
In the groove 202g, physical address information indicating the position on the disk is recorded in advance as wobble corresponding to the FM modulated wave. At the time of data recording, the address information is read and data recording based on the address information is performed.

  When reproducing the data recorded in this way, as schematically shown in FIG. 2, the laser beam is focused and controlled on the groove 202g, and the laser beam is irradiated along the groove 202g. During reproduction, a laser beam having a weaker intensity than that during recording is irradiated. At this time, the recorded data is reproduced by demodulating the light (returned light) signal reflected from the optical disc 200 (reflective layer 203).

  Further, the recording layer 202 (groove 202g) has a property of changing color when irradiated with laser light having a certain intensity (amount of heat). For this reason, when a visible image is formed on the optical disc 200, the laser beam is irradiated along the groove 202g as in the case of data recording. When a laser beam with a certain intensity (amount of heat) is irradiated, the irradiated portion of the groove 202g changes color, thereby forming a visible image.

4A to 4C show specific examples in which a visible image is formed on the optical disc 200 (recording layer 202). 4A is an overall view of the optical disc 200, and shows an example in which the alphabet letter “A” is formed as a visible image in the area 41 on the optical disc 200 as shown in FIG.
FIG. 4B is an enlarged view of the area 41. And FIG.4 (c) is the figure which expanded further the area | region 42 shown in FIG.4 (b). FIG. 4C is an upside down view for clarifying the comparison with the data recording (FIG. 3). In this manner, a visible image “A” is formed as a whole by changing a part of the groove 202g.

In this way, both during data recording (FIG. 3) and when a visible image is formed (FIG. 4 (c)), laser light is irradiated along the groove 202g, and pit formation or partial discoloration is performed. Here, when recording data, laser light is irradiated so that pits 202p with a size of μm order are formed, but when a visible image is formed, an area with a size of mm order (a level where visibility can be discriminated) changes color. As described above, the laser beam is irradiated.
Although it is assumed that the portion where the pits 202p are formed is also discolored due to heat, as described above, since the individual pits 202p cannot be visually discriminated, the pits 202p are discolored. By doing so, the problem that the formed visible image cannot be recognized does not occur.

  Although the configuration of the optical disc 200 has been described above, the configuration of the optical disc 200 is the same as that of a conventional CD-R disc or the like except that the recording layer 202 has a property of changing color.

(Configuration of optical disk recording device)
FIG. 5 is a block diagram showing the main part of the optical disc recording apparatus 100 according to an embodiment of the present invention.
As shown in FIG. 5, the optical disk recording apparatus 100 includes an optical pickup 10, a spindle motor 11, an RF amplifier 12, a servo circuit 13, an address detection circuit 14, a decoder 15, a control unit 16, an encoder 17, a strategy circuit 18, and a laser driver. 19, a laser power control circuit 20, a data conversion unit 27, a frame memory 28, and a buffer memory 29.

The spindle motor 11 is a motor for rotationally driving an optical disc (a CD-R disc is assumed in the present embodiment) 200.
The optical pickup 10 is a unit that integrally includes a laser diode, an optical system such as a lens and a mirror, and a light receiving element for returning light.
When data is recorded on the optical disc 200 or when data recorded on the optical disc 200 is reproduced, the optical pickup 10 irradiates the optical disc 200 with laser light and receives return light from the optical disc 200. To do. The optical pickup 10 outputs an RF signal, which is an EFM (Eight to Four Modulation) modulation, which is a light reception signal, to the RF amplifier 12.
The optical pickup 10 also has a monitor diode. When a current flows through the monitor diode due to the return light of the optical disc 200, the optical pickup 10 supplies a signal corresponding to the amount of current to the laser power control circuit 20.

  The RF amplifier 12 outputs a signal indicating the level of light reflected from the optical disc 200 to the servo circuit 13 and the address detection circuit 14 when recording data or forming a visible image. When reproducing the recorded data, the EFM-modulated RF signal supplied from the optical pickup 10 is amplified, and the amplified RF signal is output to the servo circuit 13, the decoder 15, and the like.

The decoder 15 EFM-demodulates the EFM-modulated RF signal supplied from the RF amplifier 12 at the time of reproducing recorded data, and generates reproduced data.
The address detection circuit 14 extracts a wobble signal component from a signal supplied from the RF amplifier 12 during data recording or formation of a visible image, decodes address information (disc position information) included in the wobble signal component, Output to the control unit 16.
The servo circuit 13 performs rotation control of the spindle motor 11, focus control in the optical pickup 10, tracking control, and the like. The servo circuit 13 supplies a signal for driving the spindle motor 11 and the like based on the control signal supplied from the control unit 16.

  The laser power control circuit 20 is a circuit for controlling the laser power emitted from the laser diode of the optical pickup 10. The laser power control circuit 20 performs data recording and visible image formation based on the current value supplied from the monitor diode of the optical pickup 10 and the information indicating the optimum target value of the laser power supplied from the control unit 16. Therefore, the laser driver 19 is controlled so that the laser beam having the optimum laser power is emitted from the optical pickup 10.

  The buffer memory 29 stores information supplied from the host computer 110 at the time of data recording, that is, data to be recorded on the optical disc 200 (record data) in a FIFO (first-in first-out) format. The encoder 17 performs EFM modulation on the recording data read from the buffer memory 29 and outputs it to the strategy circuit 18. The strategy circuit 18 performs time axis correction processing or the like on the EFM signal supplied from the encoder 17 and outputs the result to the laser driver 19. The laser driver 19 drives the laser diode of the optical pickup 10 based on the signal modulated according to the recording data supplied from the strategy circuit 18 and the control of the laser power control circuit 20.

The frame memory 28 stores information supplied from the host computer 110 at the time of visible image formation, that is, data (image data) relating to a visible image to be formed on the optical disc 200.
This image data is a set of gradation data defining the density of dots to be formed on the disk-shaped optical disc 200 (recording layer 202). Here, in the present embodiment, a coordinate system defined by each intersection of the groove 202g and the radiation from the center of the disk is used based on the shape (spiral) of the groove 202g formed on the recording layer 202. More specifically, as shown in FIG. 6, the starting point of the groove 202g on the inner circumference of the disc is set as a reference point (one row and one column), and the first row, the second row, and the third row are sequentially arranged from the reference point toward the outer circumference of the disc. Lines, ... On the other hand, from the reference point (1 row and 1 column), it is defined as 1 column, 2 columns, 3 columns,.
In order to employ such a coordinate system, the frame memory 28 stores gradation data associated with rows and columns as shown in FIG. Since the gradation data according to the present embodiment is represented by 3 bits, an image having 8 gradations (2 to the 3rd power) gradation per dot is formed.
Since physical address information is recorded in the groove 202g (wobble modulation recording), gradation data associated with this address information may be prepared.

The image data stored in the frame memory 28 is sequentially read out one dot at a time by the control unit 16 and supplied to the data conversion unit 27.
The data conversion unit 27 performs a time axis correction process on the gradation data supplied from the frame memory 28 and outputs it to the laser driver 19. The laser driver 19 drives the laser diode of the optical pickup 10 based on the signal supplied from the data converter 27 and the control of the laser power control circuit 20.

The control unit 16 includes a CPU 30 (Central Processing Unit) 31 and a memory 30 including a ROM (Read Only Memory) and a RAM (Random Access Memory). The control unit 16 controls each unit of the optical disc recording apparatus 100 in accordance with a predetermined control program stored in advance in the memory 30 to control the focus servo mechanism, the tracking servo mechanism, and the recording power value for performing data recording. Control and drive control of the spindle motor 11 are performed.
The above is the description of the configuration of the optical disc recording apparatus 100.

(About data recording method)
Next, a specific operation of the optical disc recording apparatus 100 will be described.
First, a data recording method employed by the optical disc recording apparatus 100 according to the present embodiment will be described. In the present embodiment, it is assumed that a track-at-once method (TAO method) is adopted. The TAO method is a recording method that is widely used to enable additional recording (writing) of data.

  According to the TAO method, as schematically shown in FIG. 8, data recording to the optical disc 200 is performed a plurality of times (additional recording), and then lead-in information and lead-out information are recorded. The lead-in information is information indicating the start position of the data area, and the lead-out information is information indicating the end of the data area. Here, the process of recording the lead-in information and the lead-out information is called a close process, and data appending is prohibited for an optical disc on which the close process has been performed.

When the close process is not performed, address information indicating the end position of data recording is recorded in a program memory area (PMA) of the disk. The PMA area is an area predetermined by the disc standard (Orange Book) and is located on the inner circumference side of the disc.
The next time data is recorded (additional recording), the address recorded in the PMA area follows the designated position. In this way, in the TAO method, data can be recorded on the disc without any gap.
The above is the outline of the recording method (TAO method) used in this embodiment.

(Operation when recording data)
Next, a specific operation content when data is recorded on the optical disc 200 and when a visible image is formed using the optical disc recording apparatus 100 will be described. First, the operation during data recording will be described.
FIG. 9 is a flowchart showing the control contents of the control unit 16 when performing data recording. Hereinafter, this flowchart will be described.
When the user sets the optical disc 200 in the optical disc recording apparatus 100 and gives an instruction to start data recording, the control unit 16 controls each part of the apparatus and records data on the optical disc 200. The operation content at the time of data recording is the same as that of the conventional apparatus. The operation contents will be described below.

The control unit 16 controls each unit of the optical disc recording apparatus 100 to reproduce the lead-in area of the set optical disc 200, and reproduces the PMA area when a recording signal cannot be obtained (step Sa10). Then, it is determined whether or not address information indicating the end position of the previous recording data is recorded in the PMA area (step Sa11).
When the determination result is affirmative, that is, when the address information indicating the end position of the previous recording data can be acquired from the PMA area (step Sa11: YES), the control unit 16 sets the disk position indicated by the address information. Then, the position of the optical pickup 10 is controlled so that the laser beam is irradiated (step Sa12). Then, data recording is started (step Sa14).
On the other hand, when the determination result is negative, that is, when the address information indicating the end position of the previous recording data cannot be obtained from the PMA area (step Sa11: NO), the control unit 16 does not yet store the optical disk 200. Determine that no data is being recorded. Then, the control unit 16 controls the position of the optical pickup 10 so that the initial position (the start position of the recording area) is irradiated with the laser light (step Sa13), and starts data recording (step Sa14).

After starting the data recording, address information indicating the laser irradiation position (recording position) is sequentially output from the address detection circuit 14 to the control unit 16. Based on the acquired address information, the control unit 16 reads the recording data stored in the buffer memory 29 and controls each unit of the apparatus to record data.
Thereafter, when the data recording is finished (step Sa15), the control unit 16 controls each part of the apparatus and records address information indicating the data recording end position in the PMA area (step Sa16).
In this way, the control unit 16 records information indicating the data recording end position in the PMA area as needed every time data recording is performed. When the data is additionally recorded, the control unit 16 performs data recording so as to follow the disk position indicated by the address information recorded in the PMA area, so that data is recorded without any gap on the disk. be able to.

Next, the control unit 16 determines whether or not a process (close process) for completely ending data recording is performed by a user instruction (step Sa17).
When the determination result is affirmative (step Sa17: YES), the control unit 16 controls each unit of the apparatus and records the lead-out information (step Sa18). The lead-out information is information indicating the end of the recording data (see FIG. 8 above). After recording the lead-out information, any additional recording on the disc is prohibited.
If the determination result is negative (step Sa17: NO), the control unit 16 ends the process without recording the lead-out information.
The above is the control content of the control unit 16 when performing data recording.

(Operation when forming a visible image)
Next, the operation content when forming a visible image will be described.
Data recording is performed from the inner circumference side to the outer circumference side of the optical disc 200. However, it is characteristic that visible image formation is performed from the outer circumference side of the optical disc 200 to the inner circumference side.
More specifically, as schematically shown in FIG. 10, visible image formation is performed in the order of visible image 1, visible image 2, and visible image 3 from the outer periphery to the inner periphery of the disc. Further, when forming each visible image (visible image 1, visible image 2, etc.), it is performed from the inner periphery to the outer periphery of the disk (the direction of the arrow shown in FIG. 10).

The reason for forming the visible image in the order from the outer periphery to the inner periphery of the disk (in the order of visible image 1, visible image 2, and visible image 3) is that the data recording direction is the reverse direction. This is to make it possible to form a visible image regardless of the progress of data recording. In other words, considering that there is no problem in forming a visible image at least in the outer peripheral area even if the data recording is not closed and the unrecorded area of the disk is not specified, In this way, a visible image is formed.
The reason why each visible image (visible image 1, visible image 2, etc.) is formed from the inner periphery to the outer periphery of the disc is as follows. That is, if a visible image is to be formed from the outer periphery to the inner periphery of the disc, the rotation control of the optical disc 200 must be performed in reverse to the data recording in order to irradiate the laser beam along the groove 202g. Yes, a special control circuit is required. Further, there arises a problem that the address information (position information) recorded in the groove 202g cannot be detected. For this reason, each visible image formation is performed from the inner periphery to the outer periphery of the disc as in the case of data recording, and the existing control circuit is used as it is, so that the address information can be detected even when the visible image is formed. This is the reason.

Next, the details of the operation will be described.
FIG. 11 is a flowchart showing the control contents of the control unit 16 when forming a visible image. When the user sets the optical disc 200 in the optical disc recording apparatus 100 and gives an instruction to form a visible image, the control unit 16 controls each part of the device and forms a visible image on the optical disc 200 as follows. To go.
In the following description, in order to distinguish from the operation contents at the time of data recording, in the case of forming a certain visible image, the start position where the visible image is formed is referred to as “start position” and the end position is referred to as “end position”. Describe as follows.

  The control unit 16 controls each unit of the optical disc recording apparatus 100 and reproduces a predetermined special area on the set optical disc 200 (step Sa20). Then, it is determined whether or not address information indicating the start position of the visible image formed last time is recorded in the special area (step Sa21). Here, the special area refers to a predetermined area in the optical disc 200. In the present embodiment, the outermost peripheral area (for example, an area corresponding to a predetermined number of tracks) of the optical disk 200 is assigned to the special area. The special area corresponds to the PMA area in data recording, and address information necessary for forming a visible image without a gap on the disk is recorded.

  When the determination result is affirmative, that is, when the address information indicating the start position of the previously formed visible image can be acquired from the special area (step Sa21: YES), the control unit 16 determines the current visible from the address information. Find the starting position to form the image. Then, the position of the optical pickup 10 is controlled so that the obtained position is irradiated with the laser beam (step Sa23), and a visible image is actually formed (step Sa24).

Details of the current visible image formation start position obtained by the control unit 16 will be described.
As described above (FIG. 10), in the present embodiment, when a plurality of visible images are formed, visible images are formed in order from the outer periphery side of the disc. In other words, the visible image is formed without a gap on the disc so that the start position of the previously formed visible image is the end position of the visible image formed this time. In the example shown in FIG. 10, the start position of the visible image 1 and the end position of the visible image 2 are the same (adjacent), and the start position of the visible image 2 and the end position of the visible image 3 are the same (adjacent). Shows the case.
In order to realize such visible image formation without a gap, address information indicating the start position of the previously formed visible image is stored in the special area of the optical disc 200. The control unit 16 obtains the current visible image formation start position from the address information obtained by reproducing the special area, and obtains the start position as follows.

In the present embodiment, it is assumed that the disc width (width in the disc radial direction) W used for one visible image formation is a predetermined constant value (for example, 5 mm) (see FIG. 10). For this reason, the control unit 16 uses, as the start position of the visible image to be formed this time, the position moved by the width W from the previous visible image formation start position indicated by the address information acquired from the special area to the inner circumference side of the disk. It asks. Note that the value of the width W may be variable depending on the content (data amount) of the visible image to be formed.
The control unit 16 controls the position of the optical pickup 10 so that the laser beam is irradiated to the start position thus obtained (step Sa23), and starts visible image formation (step Sa25).

Next, the control content of the control unit 16 when the address information indicating the end position of the previous recording data could not be acquired even after reproducing the PMA area (step Sa21: NO) will be described. In this case, the control unit 16 determines that the optical disc 200 is a disc on which a visible image has not yet been formed, and controls the position of the optical pickup 10 so that the laser beam is irradiated to a predetermined start position (step Sa24). ). Then, visible image formation is started (step Sa25).
Here, the predetermined start position refers to a position moved to the inner circumference side of the disk by the width W from the outermost circumference position of the disk where the visible image can be formed (the outermost circumference position where the groove 202g is formed). The position information related to the start position is stored in the memory of the control unit 16.

When visible image formation is started, address information indicating a laser irradiation position (image formation position) is sequentially output from the address detection circuit 14 to the control unit 16 as in the case of data recording. The control unit 16 sequentially reads the gradation data stored in the frame memory 28 at a timing based on the acquired address information, and controls each unit of the apparatus to form a visible image.
Thereafter, when the formation of the visible image is finished (step Sa26), the control unit 16 records address information indicating the start position where the formation of the visible image is started in the special area (step Sa27).

  In this way, each time the visible image is formed, the control unit 16 records the address information indicating the visible image formation start position in the special area. Then, a new visible image is formed from a position moved by the width W from the position indicated by the address information recorded in the special area, thereby forming a visible image on the optical disk 200 without a gap. Is doing.

In the description so far, for the sake of convenience, the operation contents have been described separately for data recording and visible image formation. However, these operations may be performed continuously. For example, when the user designates recording data and a visible image and gives an instruction to start an operation, the control unit 16 performs control related to data recording (the flow shown in FIG. 9), and further performs control related to visible image formation ( The flow shown in FIG. 11 may be continued. That is, since the above-described operations at the time of data recording and visible image formation are independent contents, they may be performed separately or continuously.
Furthermore, it is also possible to perform data recording and visible image formation in any order, such as performing data recording after forming a visible image. In any case, according to the optical disc 200 according to the present embodiment, it can be said that data recording and visible image formation can be executed in any order.

For example, FIG. 12 shows data recording of music data (music data 1, music data 2, music data 3) for three songs on the optical disc 200 using the optical disc recording apparatus 100, and titles ( It is a figure which illustrates the case where the visible image formation about Title1, Title2, Title3) is performed.
If the optical disk recording apparatus 100 according to the present invention is used, the data recording and the visible image formation can be performed in an arbitrary order. For example, after recording the music data 1, the title 1 of the music data 1 is displayed as the visible image. Can be formed. In this respect, the conventional apparatus is greatly different from the point that the visible image cannot be formed unless all the music data 1 to 3 are recorded and the data recording is closed.
Thereafter, after the music data 1, the music data 2 is additionally recorded and the title 2 of the music data 2 is formed as a visible image.

  Moreover, since the order of processing is arbitrary, after all the music data 1 to 3 are recorded, it is possible to collectively form visible images showing the titles 1 to 3. Conversely, the music data 1 to 3 can be recorded after the visible images showing the titles 1 to 3 are collectively formed.

As described above, according to the optical disc recording apparatus 100 according to the present embodiment, a visible image can be formed on the optical disc 200 together with the original data recording. Data recording is performed from the inner circumference side of the disc and formation of a visible image is performed from the outer circumference side of the disc without any gap on the disc. For this reason, data recording and visible image formation can be performed using the limited disk recording area (groove 202g on the recording layer 202) to the maximum extent.
Here, since the visible image is formed from the outer peripheral side of the disc, the visible image can be formed even when the data recording closing process is not performed, that is, when the unrecorded area is not determined.
By using the optical disc recording apparatus 100, data recording and visible image formation can be efficiently performed in an arbitrary order, and convenience according to the convenience of individual users can be achieved.

(Modification of the first embodiment)
The embodiment described above is merely an example of application of the present invention, and can be arbitrarily modified. Some of them are listed below.

(1) In the embodiment described above, the disk radial direction width W for forming a visible image is a constant value, but the width W may be arbitrarily set by the user. Also in this case, the control part 16 should just perform control similar to the above-mentioned embodiment. That is, the control unit 16 controls the position of the optical pickup 10 so that the laser beam is irradiated to the position moved from the start position of the previously formed visible image to the inner circumference side by the specified width. Then, by starting the formation of a visible image by controlling each part of the apparatus, the same effects as those of the above-described embodiment can be obtained.

(2) In the above embodiment, a special area is provided on the optical disc 200, and address information indicating the start point of the previously formed visible image is recorded as needed. Instead of providing a special area in this way, address information may be recorded at the start position or end position of the formed visible image.
That is, the disk area required for recording address information is at most about one track, and cannot be visually discriminated. For this reason, even if address information is recorded adjacent to the formed visible image without providing a special area separately, a visible problem does not occur.

(3) In the above-described embodiment, a visible image is formed by irradiating laser light along the groove 202g and changing a part of the groove 202g. According to such control, a visible image can be formed with a resolution of an interval (track width) at which the groove 202g is formed.
However, when high resolution up to the track width (μm order) is not required, image formation may be performed by irradiating laser light without being along the groove 202g. For example, focus control is performed so that the irradiation spot diameter of the laser beam irradiated onto the optical disc 200 (recording layer 202) is increased, and a plurality of adjacent grooves 202g are discolored all at once to form a visible image. It may be. Further, a visible image may be formed by wobbling laser light in a range extending over a plurality of adjacent grooves 202g.

Also in this modification, the control content until the start position for forming the visible image is found is the same as in the above-described embodiment. That is, the control unit 16 reproduces the special area of the optical disc 200 and obtains address information indicating the previous visible image formation start position. Then, the current visible image formation start position is found from the address information.
Here, when reproducing the special area, it is necessary to focus the laser beam on the groove 202g (of the special area), so the control unit 16 controls each part of the apparatus, and the laser beam irradiation is performed along the groove 202g. To be done. When a visible image is actually formed, it is not necessary to irradiate laser light along the groove 202g. Therefore, the control unit 16 controls each part of the apparatus, and the laser light irradiation spot diameter on the optical disc 200 increases. Or the laser beam irradiation spot is wobbled. Then, a visible image is formed by changing the color for each groove 202g for a plurality of tracks.
Also in this modified example, as in the above-described embodiment, visible image formation is performed without any gap on the disk in order from the outer peripheral side of the disk. For this reason, data recording and visible image formation can be performed using the limited disk recording area (groove 202g on the recording layer 202) to the maximum extent. The same is true in that a visible image can be formed regardless of the progress of data recording (even at a stage where the closing process is not performed).

B: Second Embodiment In the above-described embodiment, in order to form a visible image on the optical disc 200 without a gap, address information indicating the start position of the previously formed visible image is recorded in a predetermined region (special region) of the optical disc 200. I was trying to do it.
However, from the viewpoint of visibility, it can be considered that there is no need to perform address management and form an image with no gap in the μ order. Based on this viewpoint, the optical disc recording apparatus 101 according to the present embodiment is characterized in that address management is not performed when a visible image is formed.

  FIG. 13 is a block diagram showing the configuration of the optical disc recording apparatus 101 according to this embodiment. As shown in FIG. 13, the optical disc recording apparatus 101 is different from the configuration of the optical disc recording apparatus 100 according to the above-described embodiment only in that an envelope detection circuit 22 is added. For this reason, below, it demonstrates about a different part and demonstrates the same code | symbol about the component same as the above-mentioned embodiment.

The envelope detection circuit 22 is a circuit for detecting (searching) the start position of the previously formed visible image when the visible image is formed.
FIG. 14 is a diagram schematically showing the content of a signal supplied from the RF amplifier 12 to the envelope detection circuit 22 when laser light (reproduction low-level laser light) is irradiated along the groove 202g. As shown in FIG. 14, the signal supplied from the RF amplifier 12 is large in a signal S1 having a high level and a small level amplitude value (PP value: peak to peak value) and a signal S2 having a low level and a large PP width. Separated.
Among these, the signal S1 corresponds to a region where a visible image is not formed. That is, in the region where no visible image is formed, the groove 202g is kept in an unrecorded state (initial state), so that the level of the reflected signal is high and the PP value of the signal is small. . On the other hand, the signal S2 corresponds to a region where a visible image is formed. In the region where the visible image is formed, the state of the groove 202g is changed (discolored) by laser light irradiation, and the reflectance is lowered. For this reason, the signal level of the reflected light of the laser light irradiated to the said area | region becomes a low thing. Since this reflected light includes various signal components, the PP value of the signal is large.

  The envelope detection circuit 22 detects the state (level, PP value) of the signal supplied from the RF amplifier 12 in this way, and informs the control unit 16 of information on the boundary position between the region where the visible image is formed and the region where the visible image is not formed. Supply.

Next, the contents of the operation of the optical disc recording apparatus 101 according to this embodiment will be described. Since the operation at the time of data recording is the same as that of the optical disc recording apparatus 100 according to the above-described embodiment, the operation content at the time of visible image formation will be described. FIG. 15 is a flow showing the control contents of the control unit 16 at this time.
When the formation of a visible image is instructed, the control unit 16 controls each unit of the apparatus and detects the start position of the previously formed visible image (step Sa31). More specifically, laser light is irradiated along the groove 202g on the optical disc 200 (recording layer 202). Then, the boundary position between the region where the visible image is formed and the region where the visible image is not formed is obtained from the state of the envelope of the signal supplied from the envelope detection circuit 22 described above.
The boundary position obtained in this way is the same as the position indicated by the address information acquired from the special area in the above-described embodiment unless the position accuracy is taken into consideration.

The control content of the control part 16 after this is the same as that of the above-mentioned embodiment. That is, the control unit 16 controls each unit of the apparatus so that the laser beam is irradiated to the position moved in the disc inner circumferential direction by the width W from the detected boundary position (step Sa35). Then, a visible image is actually formed (step Sa36).
In this embodiment, since address management is not performed when a visible image is formed, control for recording address information in a special area is unnecessary.

  As described above, also in the optical disc recording apparatus 101 according to the present embodiment, a visible image can be formed on the optical disc 200 together with the original data recording, as in the above-described embodiment. The same is true in that data recording is performed from the inner circumference side of the disk and visible image formation is performed from the outer circumference side of the disk without any gap on the disk. For this reason, it is possible to perform data recording and visible image formation utilizing the limited disk recording area to the maximum extent. Further, since the visible image is formed from the outer peripheral side of the disc, the visible image can be formed even at the stage where the data recording process is not closed (the stage where the unrecorded area is not determined). That is, if the optical disc recording apparatus 101 is used, data recording and visible image formation can be efficiently performed in an arbitrary order, and the usability of individual users can be improved.

C: Third Embodiment In each of the above-described embodiments, visible images are formed in order from the outer peripheral side of the optical disc 200 toward the inner peripheral side. On the other hand, the optical disc recording apparatus according to the present embodiment is characterized in that a disc-shaped optical disc 200 is divided into a plurality of regions by radiation from the center, and a visible image is formed in order for each region. .

More specifically, as shown in FIG. 16, it is defined that the surface of the optical disc 200 (recording layer 202) is divided into a plurality of parts by radiation from the center of the optical disc 200. FIG. 16 illustrates a case where the area 51, the area 52,..., And the area 58 are equally divided into eight areas (hereinafter referred to as divided areas).
The optical disc recording apparatus according to the present embodiment sequentially forms visible images on the divided areas thus defined. FIG. 16 shows an example in which the visible image 1 is formed in the area 51 and the visible image 2 is formed in the area 52. After this, visible image formation is performed in the order of region 53, region 54,.

  Also in the optical disk recording apparatus according to the present embodiment, the specific control content is the same as the apparatus of each embodiment described above. FIG. 17 is a diagram illustrating one of the divided areas (area 51). As described above, in each divided area, a coordinate system defined by rows and columns is defined as described above. By performing the same control as in the above-described embodiment, a visible image can be formed regardless of the progress of data recording.

(Modification of the third embodiment)
When the resolution of the visible image to be formed is not so required, visible image formation may be performed by irradiating laser light without being along the groove 202g.
However, when the visible image is formed without being along the groove 202g, the address information indicating the laser irradiation position cannot be acquired during the visible image formation. For this reason, it is necessary to separately provide means for determining which of the divided areas the current laser light irradiation position corresponds to.

  FIG. 18 is a configuration block diagram of an optical disc recording apparatus 103 according to this modification. As shown in FIG. 18, the configuration of the optical disc recording apparatus 103 is the same as that of the above-described embodiments except that the FG circuit 21 is provided. For this reason, the description which attached | subjected the same code | symbol about the same component is performed.

The FG circuit 21 outputs a signal (FG pulse signal) 21S representing the rotation frequency of the spindle motor 11. More specifically, the counter electromotive current obtained from the motor driver of the spindle motor 11 is used to output a pulse signal 21S representing the rotation frequency of the spindle. The FG circuit 21 in the present embodiment outputs 16 pulse signals 21S while the spindle motor 11 makes one rotation.
FIG. 19 illustrates the contents of the FG pulse signal 21S. FIG. 19 shows that the horizontal axis is the time axis, and the spindle motor 11 makes one revolution, that is, the optical disc 200 makes one revolution in the time corresponding to 16 pulse signals.

At the time of visible image formation, the control unit 16 detects in which divided region (divided regions 51 to 58) the current laser light irradiation position is present from such an FG pulse signal 21S. The detection means of the control unit 16 at this time will be specifically described with reference to FIG.
As shown in FIG. 19, the FG circuit 21 outputs 16 FG pulses while the spindle motor 11 rotates once, that is, while the optical disk 200 rotates once. The control unit 16 counts the FG pulses supplied from the FG circuit 21 one by one, thereby detecting in which divided region (divided regions 51 to 58) the laser light irradiation position exists.

FIG. 19 schematically shows the timing at which the address information is supplied from the address detection circuit 14 together with the FG pulse signal 21S supplied from the FG circuit 21 to the control unit 16. As described above, the control unit 16 treats the pulse supplied from the FG circuit 21 as the reference pulse at the timing when the address information “0” is supplied from the address detection circuit 14. The address information “0” is merely an example, but is a value set in advance as address information indicating the start position of the divided area 51.
The control unit 16 detects the laser light irradiation position with reference to the reference pulse. Specifically, while two pulses including the reference pulse are supplied, it is detected that the divided region 51 is irradiated with laser. Then, while the next two pulses are supplied, it is detected that the divided region 52 is irradiated with laser. In this way, every time two pulses are supplied, it is detected that the divided area irradiated with the laser changes.
When the 16th pulse is supplied from the reference pulse, the control unit 16 detects that the region 51 is irradiated with the laser again. Hereinafter, by repeating this, the control unit 16 detects (counts) pulses supplied from the FG circuit 21, and detects in which divided region (divided regions 51 to 58) the laser light irradiation position exists. Can do it.
In actual operation, it is preferable to determine the reference pulse in consideration of the decoding processing time in the address detection circuit 14.
Further, when the optical disk 200 on which the visible image is formed using the optical disk recording apparatus 103 is taken out from the apparatus 103 and set again to form the visible image, the alignment corresponding to the divided areas 51 to 58 is performed with high accuracy. It is preferable to carry out. In such a case, the control unit 16 may control to increase the number of pulses during one rotation of the optical disc 200 based on the pulse signal supplied from the FG circuit 21. For example, if 32 pulses are obtained during one rotation of the optical disc 200, more accurate position control can be performed. As a means for increasing the number of pulses, for example, a method of supplying an output signal of the FG circuit 21 to a PLL (Phase Locked Loop) circuit (not shown) can be used.

As described above, if a method for determining a reference pulse in association with certain address information (for example, address “0”) is used, even when the optical disc 200 is reset in the optical disc recording apparatus 103, the control unit 16. Can always detect which divided region the laser beam irradiation position is in. Therefore, there is no problem that a visible image is erroneously formed in a divided area that should not be formed.
When forming a visible image, the control unit 16 detects the FG pulse signal 21S supplied from the FG circuit 21 and controls each part of the apparatus when the timing at which a visible image is to be formed. A visible image is formed as it is irradiated. At this time, the control unit 16 controls the laser light irradiation position to move to the outer peripheral side every time the optical disk 200 makes one rotation (every 16 FG pulses are detected). Similarly, a visible image can be formed without a gap on the disk.
The method for determining the reference pulse is not limited to a method using a decode address, and a method of providing a marking at a specific position on the optical disc 200 may be adopted. Specifically, marking is performed at a specific position (for example, between the PMA area and the lead-in area) on the inner periphery of the disk. Then, the reference pulse may be determined using the output signal of the envelope detection circuit 22 obtained when the specific position (specific radial position) is reproduced.

  Note that an optical disk recording apparatus that records data by rotating the optical disk 200 at a constant angular velocity (CAV: Constant Angular Velocity) generally includes the FG circuit 21 described above. The rotational speed of the disk is detected from the output pulse signal 21S. If such an optical disc recording apparatus is used, the present modification can be applied using an existing circuit as it is.

D: Modified Examples Each embodiment described above is merely an example for explaining the contents of the present invention, and can be arbitrarily modified without departing from the contents of the present invention. Below, some of the modifications are shown.

(Modification 1)
In each of the above-described embodiments, when a visible image is formed on the optical disc 200, it is assumed that data (image data) related to the visible image is supplied from an external device (host PC 110). However, this image data may be stored in advance in the optical disk recording apparatus according to each of the above embodiments.
For example, when characters such as numbers and alphabets are limited to be formed as a visible image, image data related to the characters may be stored in the optical disc recording apparatus in advance. Then, the user may select characters to be formed as an image by operating a device operation unit (not shown).

(Modification 2)
Each time data recording is performed, time stamp information related to the date and time of recording may be automatically formed as a visible image without a user instruction. The time stamp information may be supplied from the external device (host PC 110) to the optical disc recording device 100 as needed.
Alternatively, a user name may be registered in advance and automatically formed as a visible image indicating the user name. The user name is registered by operating the host PC 110 by the user. Then, it may be automatically formed every time data is recorded, or may be automatically formed when the data recording is closed.

(Modification 3)
The optical disc 200 is provided by each manufacturer, and the present situation is that the characteristics of the recording layer 202 (group 202g) are different for each manufacturer. For example, when the heat absorption rate of the recording layer 202 is different, it is assumed that the level of the laser beam to be irradiated for forming the pit 202p and the level of the laser beam to be irradiated for changing the color are different.
Therefore, data recording and visible image formation are actually performed on a large number of manufacturers' optical disks 200 in advance to determine how much laser light is suitable for irradiation, and such values are stored in the memory in the control unit 16. You may make it store in. In this case, if the identification information (disc ID information) indicating the type of the optical disc 200 is stored in association with the disc, the disc ID information of the set optical disc 200 is read, and then laser light irradiation according to the disc type is performed. can do.

1 is a side sectional view of an optical disc 200 to be recorded by an optical disc recording apparatus 100 according to a first embodiment of the present invention. 2 is a diagram for explaining the configuration of an optical disc 200. FIG. 2 is a diagram for explaining the configuration of an optical disc 200. FIG. 2 is a diagram for explaining the configuration of an optical disc 200. FIG. 1 is a block diagram showing a configuration of an optical disc recording apparatus 100. FIG. It is a figure for demonstrating the basic principle at the time of forming a visible image. It is a figure for demonstrating the content of the image data for forming a visible image. It is a figure for demonstrating the TAO system which is one of the recording systems. It is a flowchart which shows the operation | movement content of the control part 16 at the time of data recording. It is a figure for demonstrating the basic operation | movement at the time of visible image formation. It is a flowchart which shows the operation | movement content of the control part 16 at the time of visible image formation. FIG. 10 is a diagram for explaining an operation effect of the optical disc recording apparatus 100. It is a block diagram of the configuration of an optical disc recording apparatus 101 according to a second embodiment of the present invention. 4 is a diagram for explaining the operation of an envelope detection circuit 22. FIG. 5 is a diagram for explaining a basic operation of the optical disc recording apparatus 101. FIG. It is a figure for demonstrating the basic operation | movement of the optical disk recording device which concerns on 3rd Embodiment of this invention. It is a figure for demonstrating the basic operation | movement of an optical disk recording device. It is a block block diagram of the optical disk recording device 103 which concerns on the modification of 3rd Embodiment. 6 is a diagram for explaining a basic operation of the optical disc recording apparatus 103. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Optical pick-up, 11 ... Spindle motor, 12 ... RF amplifier, 13 ... Servo circuit, 14 ... Address detection circuit, 16 ... Control part, 17 ... Encoder, 18 ... Strategy circuit, 19 ... ... Laser driver (driver), 20 ... Laser power control circuit (LPC), 22 ... Envelope detection circuit, 27 ... Data converter, 28 ... Frame memory, 29 ... Buffer memory, 100 ... Optical disk recording device , 200 ... optical disc, 201 ... protective layer, 202 ... recording layer, 202 g ... groove, 202 p ... pit, 203 ... reflective layer, 204 ... protective layer

Claims (5)

An optical pickup that irradiates a laser beam to an optical disc having a disk-shaped recording layer and having a recording layer that is discolored by heat or light;
Visible image forming means for forming a visible image by irradiating the recording layer with laser light from the optical pickup and partially changing the color of the recording layer sequentially from the inner periphery of the disk,
A first visible image is sequentially formed from a position on the inner circumference side of the disk by a predetermined distance from a predetermined end position in any of a plurality of divided areas obtained by dividing the recording layer by radiation from the center of the optical disk. Forming ,
After the first visible image is formed, a position on the inner periphery side of the disc by a predetermined distance from a predetermined end point position in a divided area in which the first visible image is not formed among the plurality of divided areas. And an visible image forming means for forming a second visible image in order . The optical disk recording apparatus according to claim 1,
Have a position detecting means for the irradiation position of the laser beam in the optical disc to detect which of the plurality of divided regions,
The visible image forming unit is configured to irradiate a laser beam to a divided region including the irradiation position detected by the position detecting unit when the laser beam irradiation position is moved from the inner circumference side to the outer circumference side. An optical disk recording apparatus characterized by forming an image . In the optical disk recording apparatus according to claim 1 or 2,
The optical disc is an optical disc having a recording layer in which guide grooves are spirally formed,
An optical disk recording apparatus comprising data recording means for recording data by irradiating laser light from the optical pickup along the guide groove and forming pits in order from the inner periphery of the disk. The optical disk recording apparatus according to any one of claims 1 to 3,
The optical disc is an optical disc having a recording layer in which guide grooves are spirally formed,
The visible image forming means forms a visible image by irradiating a laser beam from the optical pickup along the guide groove on the recording layer, and partially changing the color of the recording layer in order from the inner peripheral side of the disc. An optical disc recording apparatus characterized by: The optical disk recording apparatus according to any one of claims 1 to 4,
Drive means for rotationally driving the optical disc;
Feed means for sequentially moving the optical pickup in the outer peripheral direction of the optical disc;
The visible image forming unit irradiates the recording layer of the optical disk rotated by the driving unit with a laser beam from the optical pickup, and uses the feed unit to determine a laser beam irradiation position on the recording layer. An optical disk recording apparatus, wherein the optical disk recording apparatus is moved from the inner circumference side to the outer circumference in order.

Images