JP2004014082A - Optical disk write system, and optical disk write method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical disk write system which records information desired by a user on a recording surface in a way the write is visually recognizable. <P>SOLUTION: A synchronizing signal output means detects the rotation of an optical disk and outputs a synchronization signal synchronized with the rotation. Then, an image write means radiates laser light on the basis of the synchronization signal and, for example, image data which the user desires to write on the recording surface. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an optical disk writing device and an optical disk writing method, and more particularly to an optical disk writing device and an optical disk writing method that employ the CLV method.
[0002]
[Prior art]
In recent years, the size of a program used in a personal computer or the like and the size of data used in the program tend to increase. The reasons are that the program has a higher function, and that the opportunity to handle relatively large-sized audio data, image data (still image data, moving image data), and the like has increased.
[0003]
In addition, optical disks are increasingly used as media for recording such large-sized data (including programs). This is because the storage capacity per unit is large and the cost is relatively low. However, it is considered that the general user can write data on the optical disc.
[0004]
When writing data to the optical disk, an optical disk writing device is used. The optical disk writing device is specifically a CD-R (CD Recordable) drive, CD-RW (CD-ReWriteable) drive, DVD-R drive, DVD-RAM drive, DVD + R drive, DVD + RW drive, or the like.
[0005]
An example of the mechanism of the optical disk writing device will be briefly described with reference to FIGS. The optical disk writing device 601 shown in FIG. 6 is an example using a CLV (Constant Linear Velocity) method. The CLV means "constant linear velocity", and is a method of keeping the moving speed (linear velocity) of a writing portion constant irrespective of the inner circumference / outer circumference of the optical disk, and by controlling the rotation speed of the motor. When reading / writing the inner circumference, the rotation speed is changed, and conversely, when reading / writing the outer circumference, the rotation speed is changed slowly.
[0006]
In the conventional optical disk writing device 601 described below, the motor 607 rotates the optical disk 606, the reflected light obtained from the guide groove provided on the optical disk 606 is detected by the light receiving unit 610, and based on the detected state, The motor control unit 611 controls the motor 607.
[0007]
Further, the rotation is also detected by the photo interrupter 608, and information about the rotation is transmitted to the speed detection unit 609, so that the speed detection unit 609 can obtain the rotation speed of the motor 607. That is, the photointerrupter shines light on a light reflector attached to, for example, the shaft of the motor 607, detects light reflection by the reflector, and generates an electric signal having a frequency proportional to the reflection. . Subsequently, the speed detecting means 609 calculates the rotation speed of the motor based on the frequency of the electric signal.
[0008]
Data to be written on the optical disk 606 is received from, for example, a personal computer or the like via an interface (I / F) 602, for example. The I / F 602 is, for example, a SCSI interface.
[0009]
The data received via the I / F 602 is once converted into a predetermined format by the write signal generation means 603. The predetermined format is, for example, a format conforming to the standard of the optical disc.
[0010]
The converted data is transmitted from the write signal generation unit 603 to the laser drive unit 604 based on the rotation speed calculated by the speed detection unit 609 and the crystal transmission unit 612 that outputs a constant pulse. The laser driving means 604 writes the converted data on the recording surface of the optical disc 606 by controlling the laser 605.
[0011]
As a method different from the CLV method, there is a CAV (Constant Angular Velocity) method. The CAV means “constant angular velocity”, and is a method of reading and writing data at a constant rotational speed. That is, since the circumference becomes longer toward the outside, the speed at which the laser traces the writing portion becomes faster toward the inside and becomes slower toward the outside, and accordingly the output of the laser is controlled.
[0012]
In the optical disk writing device 701 using the CAV method shown in FIG. 7, the motor 707 rotates the optical disk 706, and the light receiving unit 710 detects the reflected light obtained from the guide groove provided in the optical disk 706, and the detected light is detected. Based on the state, the write clock generating means 712 outputs a write pulse required for writing. The write signal generation unit 703 that has received the pulse outputs data to the laser drive unit 704 based on the pulse.
[0013]
The data is transmitted from, for example, a personal computer via the I / F 702 and is converted into a predetermined format by the write signal generation means 703 in the same manner as in the CLV.
[0014]
Meanwhile, the rotation of the optical disk 706 in the above CAV is kept constant (constant angular velocity). This is realized by the rotation of the motor 707 being detected by the photo interrupter 708, and the motor control means 711 controlling the motor 707 based on the detected state.
[0015]
Next, the principle of recording data on an optical disk (here, a CD-R) will be briefly described with reference to FIG. FIG. 8A is an image diagram of a cross section provided in a direction perpendicular to a guide groove (described later) provided spirally on the optical disc. In this example, the optical disc 801 includes a protective layer 802, a reflective layer 803, a recording layer 804, and a base 805. The base 805 is provided with a guide groove called a groove, and data is recorded along the groove. The lower surface is a recording surface, and the upper surface is a label surface on which a user can write letters or the like or attach a seal or the like.
[0016]
For example, when a laser beam 806 emitted from a laser 605 hits a groove, the recording layer 804 absorbs the laser beam 806 and locally generates heat, whereby the substrate 805 is deformed. In addition, the refractive index of the recording layer 804 at the portion irradiated with the laser beam 806 changes due to the decomposition of the dye. FIG. 8B shows a state in which the base is deformed. It can be seen that part of the recording layer 804 is depressed in the protective layer 802 direction before recording (before laser irradiation). In this state, the light interference condition of the irradiated portion changes compared to before the laser irradiation, and the same effect as that of the recording pit on the CD occurs, that is, data is recorded as a signal.
[0017]
As described above, data can be written to the optical disk. In the CLV, for example, since the linear velocity is constant, on / off control of the laser irradiation is performed at the same output and at the same interval per bit throughout. However, in the above CAV, since the linear velocity is different between the inner peripheral part and the outer peripheral part, for example, the on / off interval of laser irradiation is shorter in the outer peripheral part than in the inner peripheral part. Therefore, it is necessary to control the laser output so as to increase the laser power.
[0018]
When the data recording locations are gathered to some extent, it is possible to visually recognize the locations where the writing process has been performed and the locations where the writing process has not been performed in a large range.
[0019]
[Problems to be solved by the invention]
By the way, on a conventional optical disk, information desired by a user can be written on a label surface with, for example, a pen or printed on a sticker or the like, and pasted. However, the user could not write information on the recording surface because of an obstacle in reading data. If any information is written on the recording surface with a pen or the like or a sticker is attached, data cannot be read from the optical disc.
[0020]
Some DVD-RAMs currently on the market, for example, do not have a label surface and both sides have a recording surface. The information desired by the user cannot be written on such an optical disk, and when the user manages the optical disk, it is necessary to take a method of writing information on the case of the optical disk. However, there is a case where the optical disc is used out of the above case, and in such a case, there is no method of discriminating a plurality of optical discs other than reading and confirming data.
[0021]
The present invention has been proposed based on the above-mentioned conventional circumstances, and has as its object to provide an optical disk writing device capable of writing information desired by a user on a recording surface so as to be visually recognizable. I do.
[0022]
[Means for Solving the Problems]
The present invention employs the following means to achieve the above object. That is, as shown in FIG. 1, the present invention is premised on an optical disk writing device that writes data by rotating an optical disk and irradiating the optical disk with laser light.
[0023]
Here, the synchronization signal output means detects the rotation of the optical disk and outputs a synchronization signal synchronized with the rotation. Subsequently, the image writing unit irradiates a laser beam based on the synchronization signal and, for example, image data that the user desires to draw on the recording surface.
[0024]
As described above, it is possible to draw an image corresponding to the image data desired by the user on the recording surface of the optical disc so as to be visually recognizable.
[0025]
Further, a configuration may be adopted in which a synchronization signal in which one side of image data is assigned to one rotation of the optical disk is output. Specifically, the same number of pulses as the number of dots corresponding to one side of the image data are output per rotation of the optical disk.
[0026]
This makes it possible to eliminate seams between images to be drawn on the recording surface. This makes it possible to draw the image beautifully on the recording surface, for example, when an image that can be combined seamlessly at both ends is used as image data, such as when a predetermined pattern is repeated.
[0027]
Note that the synchronization signal output means may be a PLL circuit that detects rotation of the optical disk using a photo interrupter and outputs a synchronization signal based on a signal from the photo interrupter.
[0028]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings to provide an understanding of the present invention. It should be noted that the following embodiments are examples embodying the present invention and are not intended to limit the technical scope of the present invention.
[0029]
FIG. 1 is a schematic functional block diagram of an optical disk writing apparatus according to the present embodiment, and its configuration will be described below focusing on points different from the above-described conventional one. The optical disk writing apparatus 101 shown in FIG. 1 uses the CLV method, that is, is controlled so that the linear velocity becomes constant. It is also assumed that it is connected to a personal computer (not shown) via the I / F 102, for example.
[0030]
First, the user prepares image data to be visually recognizable, for example, on a recording surface of an optical disc (in this example, a CD-R) (FIG. 2: S201). The preparation of the image data is performed, for example, as follows.
[0031]
An example of the image data is shown in FIG. 3 for understanding. The image data 301 is provided as bitmap data having data of, for example, 5120 dots in the X-axis 302 direction and 32 dots in the Y-axis 303 direction.
[0032]
For example, characters and images are expressed in the 5120 dots × 32 dots constituting the image data 301. The image data is transmitted from the personal computer to the image storage unit 112 via the I / F 102, and is temporarily stored in the image storage unit 112. Note that the image data is provided as bitmap data, but the image data may be in any format, as long as it can respond to on / off of a laser described later. Further, for example, image data may be provided in a JPEG format and converted into bitmap data when data is written by an image writing unit described later.
[0033]
When the preparation of the image data 301 is completed, the user subsequently inputs a writing start position on the optical medium, where the image data 301 is written (FIG. 2: S202). The write start position is given, for example, by a distance (radius) from the center of the optical medium 106, but any method may be used as long as the position on the optical disk 106 can be specified. Here, the writing start position is given by a distance 501 from the innermost circumference 502 of the recording surface.
[0034]
The method of transmitting the writing start position to the image writing unit 111 may be any method. That is, for example, the image data may be transmitted from the personal computer to the image writing unit 111 via the I / F 102. Further, the image writing unit 111 may be provided with a different interface (for example, RS232C), and may be transmitted through the interface. To the image writing means 111. Upon receiving the writing start position, the image writing unit 111 stores the received position in, for example, a predetermined memory included in the image writing unit 111.
[0035]
When the input of the image file and the input of the position where the image is to be written are completed, the writing of data to the optical medium 106 is started (FIG. 2: S203).
[0036]
When writing to the optical medium is started, first, the motor 107 rotates the optical disk 106, and the light receiving unit 114 detects reflected light obtained from a guide groove provided in the optical disk 106, and the detected state is obtained. The motor control means 115 controls the motor 107 based on.
[0037]
The rotation is also detected by the photo-interrupter 108, and information on the rotation is transmitted to the speed detecting means 109. The detection method is the same as that described in the related art. In this embodiment, the number of pulses output from the photo interrupter 108 when the optical disk 106 makes one rotation is 40 pulses. The information (pulse) related to the rotation from the photointerrupter 108 is transmitted to the speed detecting means 109, and the rotation speed of the optical disk 106 is calculated and given to the write signal generating means 103. It is the same as that.
[0038]
However, in the present embodiment, the information (pulse) related to the rotation output from the photo interrupter 106 is further input to the synchronization signal output unit 110. Here, for example, the synchronizing signal output means 110 is provided as a PPL (Phase Locked Loop) circuit. That is, the synchronizing signal output unit 110 obtains 128 of the information related to the rotation based on the number of dots in the X-axis 302 direction of the image data (here, 5120 dots) and the information related to the rotation (40 pulses / rotation). A double clock is generated (5120 ÷ 40 = 128). That is, a clock corresponding to each dot in the X-axis 302 direction of the image data 301 is generated. Each dot in the direction of the X-axis 302 is data drawn along the circumference of the optical disk.
[0039]
The clock generated by the synchronization signal output unit 110 is input to the image writing unit 111. The image writing means 111 can calculate how many rotations of the optical disk 106 have started from the start of writing by counting the clock after the start of writing.
[0040]
In the present embodiment, as shown in FIG. 5, it is assumed that an image indicated by the image data 301 is drawn on the outer peripheral portion of the recording surface of the optical medium.
[0041]
Therefore, at the beginning of writing, data transmitted from the personal computer is written from the inner periphery of the optical medium as needed. That is, when writing to the optical disk 106 is started, the write signal generating means 103 converts data received from a personal computer into a predetermined format, for example, and transmits the data as needed, as described in the related art. I do. However, the transmission destination is the image writing unit 111. Subsequently, the image writing unit 111 determines whether the position (the position of the laser 105) on the optical disk 106 where writing is currently being performed is a writing start position input by the user (FIG. 2). : S204). Here, at the beginning of the writing, since the position is not the position where the image data is written, the image writing unit 111 transmits the data having the predetermined format received from the writing signal generating unit 103 to the laser driving unit 104 as it is. (FIG. 2: S204 No → S205). The laser driving unit 104 that has received the data having the predetermined format writes data on the optical disk 106 by controlling on / off of the laser light emitted from the laser 105 (FIG. 2: S206). Here, since the CLV method is employed, the output of the laser beam is constant at both the inner circumference and the outer circumference. At this point, the image writing unit 111 has not directly interposed the data writing.
[0042]
The determination of the writing start position of the image data is performed as follows. In other words, the position of the laser 105 moves little by little in the outer peripheral direction in accordance with the spirally provided groove (guide groove) on the optical disk. Here, since the distance that the laser 105 moves in the outer peripheral direction while the optical disk 106 makes one rotation is determined, the number of rotations of the optical disk 106 from the start of writing is counted, so that the recording surface of the laser 105 is The current position (distance) from the innermost circumference 502 can be calculated.
[0043]
Therefore, the image writing unit 111 can determine whether or not the laser 105 is currently at the image writing start position by counting the clock output from the synchronization signal output unit 110. is there. Here, it is assumed that the laser 105 reaches a target position after the optical disk 106 rotates 20000 times.
[0044]
Here, if the position on the optical disk 106 where writing is currently being performed (position of the laser 105) is the writing start position input by the user, image data writing processing is performed (FIG. 2: S204 Yes → S207).
[0045]
The image data writing process is performed according to the following procedure. That is, first, the image writing unit 111 extends in the X-axis 302 direction from the start end 303 of the image data 301, for example, at the clock (here, 5120 pulses / one rotation of the optical disk) output by the synchronization signal output unit 110. The dots are read out in association with each other, and for example, if the dot is white, “0” is output to the laser driving unit 104 if it is black (FIG. 4: S401). That is, information of each dot corresponding to (X coordinate, Y coordinate) = (1, 1) to (5120, 1) is sent to the laser driving unit 104.
[0046]
At this time, no data should have been transmitted from the write signal generation means 103. If the data has been transmitted, various countermeasures can be considered as error processing, but they are not directly related to the present invention. Omitted.
[0047]
As described above, by associating (assigning) the number of pulses of the synchronization signal output per rotation of the optical disk by the synchronization signal output means with, for example, one side of the image data in the longitudinal direction, for example, as shown in FIG. It is possible to eliminate the joint at the left and right ends of the image data 301.
[0048]
Thereafter, the laser driving means 104 controls the laser 105 according to the image data ("0", "1"), whereby (X coordinate, Y coordinate) = (1, 1) to (5120, 1) Is written at a predetermined position on the optical disk 106. The writing of the image corresponding to (X coordinate, Y coordinate) = (1, 1) to (5120, 1) is repeated a predetermined number of times (number of rotations) to draw on the optical disc 106. (FIG. 4: S402 No → S401). Although the number of repetitions differs depending on the optical medium, in the present embodiment, it is, for example, 64 times.
[0049]
Subsequently, after the output of the image data (X coordinate, Y coordinate) = (1, 1) to (5120, 1) is repeated a predetermined number of times, the reference address of the image data is moved by one in the Y axis 303 direction. Then, information of each dot corresponding to (X coordinate, Y coordinate) = (1, 2) to (5120, 2) is transmitted from the image writing unit 111 to the laser driving unit 104 (FIG. 4: S403). → S404No → S401)). If the image data is lost when the image data is moved by one in the direction of the Y-axis 303, the image data writing process is completed, that is, an optical disk on which the image data is drawn on the recording surface is completed (FIG. 4: S403 → S404Yes → End). ).
[0050]
As described above, by outputting a synchronization signal synchronized with the rotation of the optical disc, and irradiating the synchronization signal with laser light based on, for example, image data desired by the user, an image corresponding to the image data is output. It is possible to draw on the recording surface of the optical disc so as to be visually recognizable.
[0051]
Further, by associating the synchronization signal output per rotation of the optical disk by the synchronization signal output means with the image data, it is possible to eliminate the seam of the image drawn on the recording surface. This makes it possible to draw the image beautifully on the recording surface, for example, when an image that can be combined seamlessly at both ends is used as image data, such as when a predetermined pattern is repeated.
[0052]
In the above embodiment, an optical disk writing apparatus using the CLV method is described. On the other hand, for example, it is considered that drawing can be performed on the recording surface of the image data by an optical disk writing device using the CAV method, but the following problem occurs.
[0053]
In other words, when the CAV method is adopted, it is necessary to change the laser light on / off interval and the laser output depending on the difference in the recording location (inner circumference, outer circumference). In this case, information on the rotation obtained from, for example, a photo interrupter alone is not enough to change the on / off of the laser beam and the laser output. Therefore, it is necessary to separately prepare a complicated circuit for controlling the laser. Furthermore, more complicated control is required in order for the difference in the output of the laser to visually appear in the drawing.
[0054]
Further, when the CAV method is adopted, even if the control accuracy for keeping the motor rotation speed constant can be controlled with an accuracy of, for example, 1/512, for example, as in the case of this embodiment, for example, 5120 dots of one circumference are used. In the case of an image, a seam having a distance of 10 dots is formed. Since it is difficult to completely reduce the speed control error to zero, a seam is inevitably formed, which is not particularly suitable for drawing a repetitive pattern or the like.
[0055]
From the above points, it is preferable to adopt the CLV method for drawing an image.
[0056]
In the above embodiment, the values (the number of dots of image data, the number of pulses per rotation, the number of clocks of the synchronization signal output means, etc.) when the optical disk is assumed to be a CD-R are shown. Therefore, when another optical medium such as a DVD-R is used, the above values may need to be changed in some cases. In other words, it is possible to easily cope with other optical media only by changing the above values.
[0057]
Further, the image storage unit 112 provided in the optical disk writing device 101 is not always necessary. For example, even when the image writing unit 111 becomes necessary, the image storage unit 112 can be obtained from the personal computer via the I / F 102 as needed. Good.
[0058]
Further, the image writing unit 111 may stop outputting laser light from the laser 105 by blocking data other than image data, that is, data transmitted from a personal computer. Further, by outputting dot data corresponding to the image data only from the writing start position of the image data, for example, a blank (writable) write-once disc in which an image is drawn on the outer periphery of an optical medium can be created. Is also possible.
[Brief description of the drawings]
FIG. 1 is a schematic functional block diagram of an optical disk writing device according to the present invention.
FIG. 2 is a flowchart of a process performed by the optical disc writing device according to the present invention.
FIG. 3 is an example of a configuration of image data.
FIG. 4 is a flowchart of an image data writing process.
FIG. 5 is an image diagram showing a recording surface of an optical disk after writing image data.
FIG. 6 is a schematic functional block diagram of a conventional optical disk writing device (CLV method).
FIG. 7 is a schematic functional block diagram of a conventional optical disk writing device (CAV system).
FIG. 8 is an image diagram of a cross section of an optical disc.
[Explanation of symbols]
101 optical disk writing device 102 I / F (interface)
103 Write signal generating means 104 Laser driving means 105 Laser 106 Optical disk 107 Motor 108 Photo interrupter 109 Speed detecting means 110 Synchronous signal outputting means 111 Image writing means 112 Image storing means

Claims (4)

In an optical disk writing device for writing data by rotating an optical disk and irradiating the optical disk with a laser beam,
Synchronization signal output means for detecting the rotation of the optical disc and outputting a synchronization signal synchronized with the rotation,
An optical disk writing apparatus comprising: an image writing unit that irradiates the laser beam based on the synchronization signal and image data corresponding to an image to be drawn on a recording surface of the optical disk. The synchronization signal output means includes:
2. The optical disk writing apparatus according to claim 1, wherein a synchronization signal in which one side of the image data is allocated to one rotation of the optical disk is output. The synchronization signal output means includes:
3. The optical disk writing device according to claim 1, wherein the rotation of the optical disk is detected using a photo interrupter, and a synchronization signal is output based on a signal from the photo interrupter. In an optical disk writing method for writing data by rotating an optical disk and irradiating the optical disk with laser light,
A detecting step of detecting rotation of the optical disc;
A synchronization signal output step of outputting a synchronization signal synchronized with the rotation,
An image writing step of irradiating the laser beam based on the synchronization signal and image data corresponding to an image to be drawn on the recording surface of the optical disk.

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