JP2007242232A - Program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent cost increase and to form an image on an optical disk at high speed and in high quality. <P>SOLUTION: The optical disk device is provided in which recording data of 24 bytes supplied from a host computer is subjected to framing, pits specified by a bit string signal of data subjected to framing are formed successively, and dot data specifying density of the dot of an image to be formed in the optical disk is replaced with recording data and supplied from a host computer when the image is formed. To the optical disk device, a discriminating device 1565 discriminating whether a part corresponding to dot data out of bit string signals is predetermined value or not is added, and a gate circuit 1567 which when the discriminated result is affirmative, passes the bit string signals therethrough over a dot period required for forming a picture of one dot, while when the discriminated result is negative, intercepts the bit string signals over the dot period is also added. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a computer program for supplying data to an optical disc apparatus to which an image forming function is added in addition to a function for recording data on an optical disc.

In recent optical disc apparatuses, an image forming function for forming images such as characters and figures is added to a recording function for recording data such as audio on an optical disc such as a CD-R (Compact Disc-Recordable). (See, for example, Patent Document 1). This type of optical disk apparatus forms images such as characters and figures by irradiating a laser beam onto a recording surface on which data is recorded and thermally changing a part of the recording surface.
JP-A-8-7530

By the way, when a new image forming function is added, if the configuration of the entire optical disc apparatus becomes complicated, the cost of the apparatus increases. In addition, if the time required to form an image on an optical disk becomes long or the quality of the formed image is low, it will not be attractive as an added value.
The present invention has been made in view of such circumstances, and an object of the present invention is to prevent an increase in the cost of the apparatus and to form an image on an optical disc with high quality without taking much time. It is an object to provide a program for supplying data to a possible optical disc apparatus.

  In order to achieve the above object, the present invention divides a recording area of an optical disc into a plurality of small areas defined by a polar coordinate system, and designates a ratio at which a pit row is formed for each of the plurality of small areas. A computer that supplies dot data to an optical disk device that interleaves dot data every predetermined number and forms pit rows at a ratio corresponding to the interleaved dot data for each area is defined by an orthogonal coordinate system Conversion means for converting the image data to be converted into the polar coordinate system, a predetermined number of dot data included in the sector when sectorizing a small region continuous in the angular direction with the same diameter in the polar coordinate system, An acquisition unit that acquires based on image data converted in the polar coordinate system, and an arrangement of a predetermined number of dot data acquired by the acquisition unit The rearranged to function as a supply means for supplying to the optical disk device.

  As described above, according to the present invention, there is provided a program for supplying data to an optical disc apparatus that prevents an increase in cost and forms an image on an optical disc at high speed and high quality.

  Embodiments of the present invention will be described below with reference to the drawings.

<First Embodiment>
FIG. 1 is a block diagram showing the configuration of the entire system including the optical disc apparatus according to the first embodiment of the present invention. As shown in this figure, the system 1 has a configuration in which an optical disk device 100 according to the embodiment is connected to a host computer 10. Among these, the host computer 10 has a configuration in which a CPU 20, a ROM 22, a RAM 24, an HDD (hard disk drive) 26, a display unit 28, an operation unit 30 and an interface 32 are connected to each other via a bus 21. Among them, the HDD 26 stores an application program for image formation in addition to the operation system, while the CPU 20 executes the application program to construct a functional block to be described later, processes the image data, and processes the optical disc apparatus. 100. In this embodiment, IDE (ATAPI) is used as a connection standard for the optical disc apparatus 100. The operation unit 30 is for inputting an operation instruction by a user, such as a keyboard or a mouse.

<Optical disk device>
FIG. 2 is a block diagram illustrating a detailed configuration of the optical disc apparatus 100. In FIG. 2, a main control unit 120 controls each unit and outputs various clock signals according to a program stored in a memory (not shown) provided therein. The optical disk 200 is set so that its recording surface faces the pickup 130 and is rotated by a spindle motor 136.
The rotation detector 138 generates, for example, eight pulses during a period in which the spindle motor 136 makes one rotation, and outputs the pulse signal as the detection signal FG. The optical disc apparatus 100 is a CAV (Constant Angular Velocity) method with a constant angular velocity. The spindle control circuit 140 feedback-controls the spindle motor 136 under the instruction from the main control unit 120 so that the rotation speed indicated by the detection signal FG is constant.

The pickup 130 is not specifically described in detail, but mainly includes a semiconductor laser (oscillator) that irradiates laser light, a light receiving element that detects the intensity of light (return light) reflected by the optical disk 200, and A focus actuator that drives the objective lens that condenses the laser light in a direction to approach or separate from the optical disc 200 and a tracking actuator that operates tracking of the laser light are integrated. The pickup 130 is screwed onto the rotation shaft of the stepping motor 144, and the rotation of the stepping motor 144 is controlled by the main control unit 120. For this reason, the pickup 130 is fed and controlled in the radial direction of the optical disc 200 by the main control unit 120.
The semiconductor laser in the pickup 130 irradiates laser light with an intensity corresponding to the drive current supplied from the laser driver 170, while the return light is converted into an electric signal by the light receiving element, and the electric signal is converted into the decoder 174, The power is supplied to the power control circuit 178 and the pickup control circuit 180, respectively.

On the other hand, the interface (I / F) 152 is for connection with the host computer 10. In this embodiment, the recording data to be recorded at the time of data recording is the image data processed as described later at the time of image formation. Are entered respectively. The buffer 154 is a first-in first-out type, in which data input by the interface 152 is temporarily stored, while the data is read in synchronization with the rotation of the optical disc 200 detected by the main control unit 120.
Although the details will be described later, the write signal generator 156 outputs a signal OEN indicating whether to irradiate the laser beam at the light level or the servo level in accordance with the data read from the buffer 154. 170. Here, the light level refers to a level sufficient to cause the recording layer to be thermally discolored to form pits when a recording layer (not shown) of the optical disc 200 is irradiated with laser light of that level. On the other hand, the servo level is a level that does not change the color of the recording layer even when the recording layer of the optical disc 200 is irradiated with the laser beam of that level, and is used when focus control or tracking control is executed.

The laser driver 170 generates a drive current corresponding to the level specified by the signal OEN and the error signal supplied from the power control circuit 178 becomes zero, and supplies the drive current to the semiconductor laser of the pickup 130.
Here, the power control circuit 178 detects the intensity of the return light of the laser light actually irradiated by the semiconductor laser from the electrical signal from the light receiving element of the pickup 130, and calculates an error between the intensity and the target intensity. Then, the error signal is supplied to the laser driver 170.
Note that the target intensity of the laser light is read and supplied as stored in the main control unit 120, and the optimum value is obtained in advance by a recording experiment or the like. Further, in the case of the CAV method with a constant angular velocity, the linear velocity increases as it goes to the outside of the optical disc 200. Therefore, the power control circuit 178 increases the target intensity of the light level as the laser beam irradiation point goes outward. Correct as follows. As described above, the intensity of the laser light emitted from the pickup 130 is appropriately controlled according to the irradiation position on the optical disc 200.

  The pickup control circuit 180 generates a focus error signal and a tracking error signal from the electrical signal from the light receiving element of the pickup 130 using a known technique, and drives the focus actuator in a direction in which the focus error signal becomes zero. The tracking actuator is driven in a direction in which the tracking error signal becomes zero. As a result, the objective lens is controlled to focus on the recording layer while maintaining a certain distance from the surface of the optical disc 200, and the focal portion of the laser light is on the track (pre-groove) of the optical disc 200. Tracking control is performed to follow.

<Write signal generator>
Next, a detailed configuration of the write signal generator 156 will be described with reference to FIG. The write signal generator 156 processes data using 25-byte data as one unit. Of these 25 bytes, 1 byte is added as subcode data D0, and the remaining 24 bytes are main data to be recorded such as audio data. Here, with respect to 24 bytes, in order to distinguish each byte, samples 1 to 24 are set in order.
The interleaving unit 1561 interleaves the samples 1 to 24 with the contents as shown in FIG. 4, for example. In this figure, for example, sample 3 indicates that it corresponds to the main data D7 after interleaving.
The interleave unit 1561 adds 4 bytes of parity data for correcting errors in the samples 1 to 24 between the main data D12 and D13 and 4 bytes immediately after the main data D24 during interleaving. To do. That is, parity data P1 to P4 are added immediately after the main data D12, and parity data Q1 to Q4 are added immediately after the main data D24.

Subsequently, the encoder 1562 obtains a total of 33 bytes including 1 byte of the subcode data D0, 24 bytes of the main data D1 to D24 processed by the interleave unit 1561 and 8 bytes of the parity data P1 to P4 and Q1 to Q4. Each of them is EFM (Eight to Fourteen Modulation) modulated and converted into 14 bits and framed in a format as shown in FIG.
At the time of this framing, the encoder 1562 adds the synchronization data Dframe having a predetermined bit pattern of 24 bits to the head of the frame, and the synchronization data Dframe and the subcode data D0 (after being converted into 14 bits). In this case, three combined bits are inserted between the main data D1 to D24 and the parity data P1 to P4 and Q1 to Q4. After all, one frame becomes 588 bits.

Here, the framed data constituting bits arranged in time series will be referred to as EFM data as shown in FIG. When the component bit “1” of the EFM data is converted into a waveform by level inversion, the period during which the EFM waveform (bit string signal) becomes, for example, the H level is a period during which pits should be formed on the optical disc 200 (that is, length ) And the period when the EFM waveform is at the L level defines the period of the land, which is the pit space. Here, in the EFM waveform, a unit period corresponding to 1 bit is expressed as 1T.
There are 4 possible combinations of 3 bits, “000”, “100”, “010”, “001” (both in binary notation). “+1” (decimal display) is given if the condition that “0” is continuous in the range of 2 to 10 is satisfied and the EFM waveform is at the H level, while “0” is given if the EFM waveform is at the L level. When “−1” is given, a pattern is selected such that the cumulative value per unit time (for example, 17T) is closest to “0”. For this reason, the duration of the same level in the EFM waveform is any one of 3T to 11T, and the EFM waveform has a property that the duty ratio is almost 50% no matter what part is extracted as a result. Have.

Various clock signals are supplied from the main control unit 120 to the encoder 1562 in order to execute framing. Of these, the clock signal CLK is generated by the master clock and has a period of 1T, and the clock signal / EFMsync falls every 588 periods of the clock signal CLK. Therefore, the encoder 1562 counts the clock signal CLK and resets the count result by the falling edge of the clock signal / EFMsync, thereby knowing the temporal position in the frame.
As shown in FIG. 6, the spindle control circuit 140 is configured so that the cycle of the signal xFG obtained by multiplying the frequency of the detection signal FG by the rotation detector 138 coincides with the cycle of the clock signal / EFMsync. Control the rotation. For this reason, one cycle of the multiplied signal xFG corresponds to a period in which the optical disc 200 is rotated by a minute angle. Therefore, an area corresponding to the minute angle in a track of the optical disc 200 (that is, one column in FIG. 6). (Corresponding area) is a storage area of one frame.

  The strategy circuit 1563 corrects the EFM waveform and outputs it as a signal OENa. As described above, the EFM waveform defines the pits (and lands) to be formed on the optical disc 200. When the EFM waveform reaches the H level of the EFM waveform, The pits formed thereby do not match the EFM waveform. The reason is that even when laser light is irradiated "as is" when the EFM waveform becomes H level, the temperature rise to the recording layer of the optical disc cannot catch up, so tears that gradually increase from thin pits Even if the laser beam is turned off as it is when the EFM waveform is at the L level when the EFM waveform is at the L level, the pits may be extended due to residual heat, etc. This is because a phenomenon that the shape of the point and the end point) is distorted occurs.

  The signal Rec is a signal supplied from the main control unit 120 and instructing data recording when it is at the H level. One of the input ends of the switch 1564 is supplied with the signal OENa from the strategy circuit 1563. When the signal Rec becomes H level and data recording is instructed, the position of the solid line in FIG. The signal OENa is supplied as it is to the laser driver 170 (see FIG. 1) as the signal OEN. Since the signal OENa is a signal obtained by correcting the EFM waveform by the strategy circuit 1563, the laser light is irradiated according to the signal modulated by the EFM waveform. On the other hand, when the signal Rec signal is at the L level and the image formation is instructed, the switch 1564 takes the position of the broken line in the figure and uses the signal OENb supplied to the other input terminal as the signal OEN to perform laser processing. This is supplied to the driver 170.

When recording data, the recording data supplied by the host computer 10 is stored in the buffer 154, and then read out sequentially as main data D1 to D24 for each byte. Further, interleaving and parity data addition are performed. Then, a pit that is framed by the encoder 1562 and matches the logic level of the EFM waveform is formed on the optical disc 200.
On the other hand, when data is reproduced, reproduction data can be obtained by irradiating the pits with laser light and supplying an electric signal indicating the return light to the decoder 174 (see FIG. 1). The decoder 174 detects the intensity of the return light from the electrical signal from the light receiving element, detects the synchronization data Dframe from the intensity change, returns it to 8 bits by EFM demodulation, and if there is a code error, it uses the parity data. Error correction is performed, and reproduction data obtained by interleaving reverse to that shown in FIG. 4 is obtained.

  Here, for convenience of description, in the present embodiment, the dot arrangement of an image formed on the optical disc 200 will be described with reference to FIG. As shown in FIG. 7A, in the optical disc 200, sectors are arranged concentrically from the inner circumference to the outer circumference from one row to m rows, and further, one column at a certain angle in the clockwise direction of the optical disc 200. To n rows. Each sector has a region equally divided into 25 in the circumferential direction, as shown in FIG. 7B. In this embodiment, this one area corresponds to a dot of an image to be formed. Therefore, in the present embodiment, the dots are arranged in m rows × 25 · n columns. In the present embodiment, this dot is binary-displayed in white or black, and 1 byte (8 bits) is assigned as dot data indicating monochrome of one dot. Here, if the dot data is “00000000” ($ 00 in hexadecimal notation), a white dot is specified, and if the dot data is data other than “00000000”, a black dot is specified. .

The white dots are not formed with pits, while the black dots are formed with pits to reduce the reflectance of the optical disc 200 and to express an image by the difference in reflectance. Thus, in this embodiment, only white or black dots are formed, but the dot data is not 1 bit but 8 bits (1 byte). As will be described later, one dot data of one sector is supplied as a subcode, and the remaining 24 dot data are supplied as main data.
Therefore, when such dot data is supplied to the write signal generator 156, it is framed in the same way as during data recording, so that it is identified as white or black and pits are defined according to the identification result. A structure to be formed is required. Therefore, the configuration for that purpose will be described below.

  In FIG. 3, a discriminator 1565 discriminates whether or not each 14 bits of the subcode data D0 and the main data D1 to D24 is data specifying a black dot. Here, the data specifying the black dot is data other than “0100100010000000” in the converted 14 bits. That is, the discriminator 1565 identifies whether or not the black dot is designated depending on whether or not the 14 bits of the subcode data D0 and the main data D1 to D24 are data other than “01001000100000”.

  Next, the time axis extender 1566 is a first-in first-out buffer memory, and writes the valid identification result by the classifier 1565 in synchronization with the slot of the EFM frame, and the written identification result is synchronized with the clock signal / Dot. Then, read out, expand in the time axis direction, and rearrange. Here, as shown in FIG. 6, the clock signal / Dot is a period of approximately 1/25 of a period obtained by excluding the output period of the synchronization data Dframe and the combined bit immediately after the period of one frame. (Dot period) A signal having DT, which is supplied from the main control unit 120.

  Subsequently, the gate circuit 1567 passes the signal OENa from the strategy circuit 1563 as it is during the period of 24T (the output period of the synchronization data Dframe) after the synchronization signal / EFMsync falls, while in the other period, In this way, the signal OENa is gated. That is, the gate circuit 1567 passes the signal OENa as it is when the rearranged identification result designates a black dot, while the signal OENa is passed when the rearranged identification result designates a white dot. Cut off. Then, the gate circuit 1567 supplies a signal obtained by gating the signal OENa to the other input terminal of the switch 1564. Therefore, when the signal Rec is at L level and an image formation is instructed, the signal OENb from the gate circuit 1567 is supplied to the laser driver 170 as the signal OEN.

<Image forming operation>
Next, an image forming operation in the system 1 will be described. First, in the host computer 10, when a user performs a predetermined operation using the operation unit 30, an image forming application program stored in the HDD 26 is activated. FIG. 8 is a flowchart showing the execution procedure of this program.
First, the CPU 20 executes editing processing such as image selection / editing / alignment (step Sa1). More specifically, the CPU 20 causes the display unit 28 to display the outer shape of the optical disc 200, selects an image to be formed, and in which position of the optical disc on which the selected image is to be formed should be arranged and formed. The image is displayed on the other hand, and the image is aligned with the optical disc by a user's operation such as cut and paste, or is appropriately deformed such as rotation or reduction. Then, the CPU 20 repeatedly executes this editing process until an image formation instruction is given (step Sa2). In other words, when an image formation instruction is given, an image to be formed on the optical disc 200 and its positional relationship are determined.

  In the image data, the dots are defined in an orthogonal coordinate system, whereas the dot arrangement of the optical disc 200 is defined in a polar coordinate system as shown in FIG. For this reason, when there is an instruction for image formation, the CPU 20 converts the image data in the orthogonal coordinate system into polar coordinates and temporarily stores them in the RAM 24 (step Sa3). Specifically, the CPU 20 obtains which of the dots defined by the orthogonal coordinate system for each of the m rows × 25 · n columns of dots on the optical disc 200 and data indicating the obtained dot density. It is determined whether or not black is specified, and the determined data is used as dot data that specifies the density of dots in the polar coordinate system. Here, as shown in FIG. 9 (a), an optical disk having a radius R when the origin of Cartesian coordinates is the upper left corner and the right direction and the lower direction are the positive direction of X and the positive direction of Y, respectively. When the center of is located at the orthogonal coordinates (R, R), the orthogonal coordinates (x, y) = (R + r · sin θ, R−r · cos θ) are established. The 25 dot data belonging to one sector are stored in the RAM 24 in a matrix in the r and θ directions in polar coordinates as shown in FIG. 9B. When the white dot is designated, the CPU 20 sets the dot data to “00000000”. However, when the black dot is designated, the dot data is data other than “00000000” and is randomly selected. Use generated one.

Next, the CPU 20 sets “1” to the variable i for specifying the row of the sector to be processed (step Sa4), and “1” to the variable j for specifying the column of the sector to be processed. Is set (step Sa5). Then, the CPU 20 reads out 25 dot data belonging to the sector of i row and j column from the RAM 24 (step Sa6). As a result, 25 dot data belonging to the sector specified by the variables i and j at the present time are acquired. When the process of step Sa6 is executed for the first time, the dot data of the sector of 1 row and 1 column is read out.
Further, as shown in FIG. 9C, the CPU 20 separates the dot data Db0 having the smallest θ component from the read dot data and supplies it to the optical disc apparatus 100 as subcode data (FIG. 8). On the other hand, the dot data Db1 to Db24, excluding the dot data Db0, are supplied to the optical disc apparatus 100 by performing the deinterleaving process (see step Sa8 in FIG. 8). The contents of the deinterleaving process are as shown in FIG. 10, and are the contents obtained by inverting the contents (see FIG. 4) of the interleaving unit 1561 in the optical disc apparatus 100.

When 25 dot data belonging to one sector are processed, the CPU 20 determines whether or not the variable j is equal to n which is the maximum number of columns (step Sa9). If the determination result is negative, the CPU 20 increments the variable j by “1” in order to move the sector to be processed to the next row (step Sa10), and returns the processing procedure to step Sa6. On the other hand, if the determination result is affirmative, it is further determined whether or not the variable i is equal to m which is the maximum value of the number of rows (step Sa11). If the determination result in step Sa11 is negative, the CPU 20 increments the variable i by “1” in order to shift the sector to be processed to the next row (step Sa12), and returns the processing procedure to step Sa5. . On the other hand, if the determination result in step Sa11 is affirmative, it means that processing has been completed up to the last sector of m rows and n columns, and the CPU 20 ends this program.
Through the circulation of steps Sa4 to Sa12, the sector processing target is 1 row 1 column, 1 row 2 columns,..., 1 row n column, 2 rows 1 column, 2 rows 2 columns,. 1 column, 3 rows and 2 columns,..., 3 rows and n columns,..., M rows and 1 columns, m rows and 2 columns,..., M rows and n columns, and 25 sectors belonging to the sector to be processed Among the dot data, the dot data Db0 is sub-code data, and the dot data Db1 to Db24 are deinterleaved and supplied to the optical disc apparatus 100, respectively.
Note that when transferring dot data to the optical disc apparatus 100, a RAW mode is used in which data corresponding to 98 frames is transferred as a single block.

Next, an image forming operation in the optical disc apparatus 100 will be described. The operations of the interleave unit 1561, the encoder 1562, and the strategy circuit 1563 in FIG. 3 are the same as those at the time of data recording except that the data is dot data.
For this reason, after the dot data supplied from the host computer 10 is stored in the buffer 154, every time the optical disk 200 rotates by a small angle, that is, by one column, 25 dot data belonging to one sector are read out. Among these, the dot data Db0 is directly supplied to the encoder 1562 as the subcode data D0, while the dot data Db1 to Db24 are supplied to the interleave unit 1561. However, since the dot data Db1 to Db24 are subjected to the deinterleaving process in advance by the host computer 10, when interleaved by the interleaving unit 1561, the sample order is again shown in the EFM frame as indicated by the broken line in FIG. Will be arranged.
The encoder 1562 sets the dot data Db0 as the subcode data D0 and frames the dot data Db1 to Db24 rearranged in the sample order as main data D1 to D24. At the time of this framing, the synchronization data Dframe and the parity data P1 to P4 and Q1 to Q4 are added as in the case of data recording. For this reason, even during data recording, the duty ratio of the EFM waveform is almost 50% regardless of which part is extracted from the EFM waveform (see FIGS. 5 and 11).

  The discriminator 1565 discriminates whether or not each of the subcode data D0 and the main data D1 to D24 converted into 14 bits by the encoder 1562 designates a black dot as described above. Here, the synchronization data Dframe, parity data P1 to P4 and Q1 to Q4 added at the time of framing have no meaning at the time of image formation. Therefore, the discriminator 1565 receives the clock signal CLK and the synchronization signal / EFMsync, detects the temporal position in the frame in the same manner as the encoder 1562, and the detected temporal position is the subcode data D0 and the main signal. The identification result is valid only when it is the output period of data D1 to D24, and when it is the output period of other synchronous data Dframe, parity data P1 to P4 and Q1 to Q4, the identification result is A signal indicating invalidity is output. Further, since it can be considered that the identification unit 1565 requires time for identification, the output of the identification unit 1565 is output with a delay of one slot (17T).

  The output result of the discriminator 1565 is as shown in FIG. 11, and the discrimination result of the 14-bit data output in the slot period of the synchronization data Dframe, the parity data P1 to P4 and Q1 to Q4 is invalid. The effect is indicated by a bar. For this reason, valid identification results are unevenly arranged over one frame, but once written in the time base expander 1566, they are read out in synchronization with the clock signal / Dot. As shown in the figure, since the slot periods of the parity data P1 to P4 and Q1 to Q4 are reduced, they are rearranged almost uniformly over one frame excluding the slot period of the synchronization data Dframe.

When the identification result is the designation of white dots, the gate circuit 1567 is closed during the rearranged period. For this reason, since the laser beam is irradiated at the servo level, pits are not formed and the reflectance of the recording layer does not change.
On the other hand, when the identification result is the designation of black dots, the gate circuit 1567 opens over the rearranged period DT, that is, in a period of 100% of the period DT. For this reason, since the laser light is at the write level when the signal OENb output during the period is at the H level, a pit is formed on the optical disc 200. Here, the signal OENb is a signal corrected by the strategy circuit 1563 so that pits are formed according to the EFM waveform, and the duty ratio of the EFM waveform is approximately 50 no matter which part is extracted regardless of the EFM data. Therefore, the ratio of the sum of the lengths of the pits formed by thermal discoloration and the sum of the lengths of the lands that have not been discolored is approximately 50%. That is, since the identification results output from the time base expander 1566 are rearranged, a waveform portion unrelated to the EFM waveform used as the reference of the identification results is extracted by the gate circuit 1567, and the waveform A pit is formed according to the portion, but even if a waveform portion not related to the identification result is extracted and a pit is formed according to the waveform portion, the ratio of the pit / land as a result is 1: 1

  FIG. 12 is a partially enlarged view of the optical disc 200 in which pits are formed in this way, and the letter “A” is displayed. The pits 202P are formed along the pregroove 202G of the optical disc 200 by tracking control, and the ratio of the pits 202P per dot is constant at about 50%. For this reason, when viewed macroscopically, the black dots are visually recognized as having the same density.

According to the first embodiment, the configuration necessary for adding the image forming function is the discriminator 1565, the time base expander 1566, the gate circuit 1567, and the switch 1564. Therefore, the cost of the apparatus can be prevented from increasing. In addition, the length in the circumferential direction in one sector is 163 μm when the linear velocity is 1.2 m / sec at the outermost circumference that is the largest, and in this embodiment, 25 dots are in the circumferential direction in one sector. Therefore, sufficient resolution can be obtained. The reason why the length in the circumferential direction in one sector is 163 μm in the outermost circumference is that 24 bytes of main data is stored in one frame, which corresponds to six samples of 16-bit 2-channel audio data. Furthermore, since this sampling period is 44.1 kHz, one period of one frame is 136 μsec.
Further, the data flow at the time of image formation is the same as that at the time of data recording except that it branches to a discriminator 1565, a time base expander 1566, and a gate circuit 1567. Therefore, the time required for image formation and the time required for data recording are almost the same if the data amount is the same, and thus there is no inconvenience that a long time is required for image formation.

  Since the gate circuit 1567 passes the signal OENa during the period when the synchronization data Dframe is output, pits are formed on the optical disc 200 in a pattern corresponding to the synchronization Dframe. It is considered that the influence on the visibility of is small. In addition, since the synchronization data Dframe always includes the light level irradiation period, it can be used to execute the power control described above during the period. However, the synchronization data Dframe may be cut in the same manner as the parity data P1 to P4 and Q1 to Q4, and the period DT may be extended accordingly.

<Application of First Embodiment>
In the first embodiment described above, the dot is configured to be either white or black. However, intermediate gradation can be expressed by adding the following configuration. For example, in the case of expressing halftone (gray) of 50% with respect to black, the classifier 1565 is provided with a function of identifying dot data designating the gray, or a separate classifier is added. At the same time, if the identification result is dot data designating ash, a configuration may be added in which the gate period is narrowed to 50% of the dot period DT. That is, the signal OENb only needs to be passed through the dot period DT during the period specified by the dot data. Similarly, if a plurality of different halftones are dealt with, it is possible to express a large number of densities.

Second Embodiment
In the first embodiment described above, it has become possible to form an image on an optical disk in a high quality and in a relatively short time. However, even though the configuration for recording data is slight, it is necessary to add a configuration. It was. Therefore, a second embodiment that requires almost no hardware configuration change will be described.
FIG. 13 is a block diagram showing the configuration of the write signal generator 156 according to the second embodiment. As shown in this figure, in the second embodiment, as compared with the configuration of FIG. 3, the discriminator 1565, the time base extender 1566, the gate circuit 1567, and the switch 1564 are not present. Further, in the strategy circuit 1563a, the correction content at the time of image formation is changed from the correction content at the time of data recording by the instruction information WS from the main control unit 120. Other configurations are the same as those in the first embodiment.

In the second embodiment, a white dot is designated if the dot data is $ D2 (hexadecimal notation), and a black dot is designated if the dot data is $ 82. Here, $ D2 is “10001001001001” in 14 bits after conversion, and is a pattern in which the level is inverted at the “/” portion of / 4T / 3T / 3T / 3T / in terms of the EFM waveform. Similarly, $ 82 is “1000010000001” in 14 bits after conversion, and is a pattern in which the level is inverted at the “/” portion of / 5T / 5T / 3T / in terms of the EFM waveform. Both of these two 14 bits are “1” at both ends. For this reason, only “000” satisfying the condition that two or more “0” s continue between “1” s among the above four patterns is selected as a combined bit interposed between the two.
Therefore, when only $ D2 and $ 82 are used as the dot data Db0 to Db24, the slot period from the subcode data D0 to the main data D12 and the slot period from the main data D13 to the main data D24 in the EFM frame. In this case, only 3T, 4T, and 5T patterns appear even if combined bits are included.

The strategy circuit 1563a corrects the EFM waveform in accordance with the following rules in consideration of the appearance of such a pattern during image formation, and outputs it as a signal OENc.
That is, the strategy circuit 1563a, when the image is formed, when the positive pulse width (H level period) of the EFM waveform is 3T or 4T, as shown in FIG. When the 2T or 3T portion at the rear end is deleted while the positive pulse width is 5T, the H level period is extended by 3T toward the front and rear of the period to become 11T, which is output as the signal OENc. .

  Therefore, in the second embodiment, when the signal OENc corresponding to white dot data is supplied to the laser driver 170, the pits 202P formed thereby become thinner and denser as shown in FIG. Change is negligible. On the other hand, when a signal OENc corresponding to black dot data is supplied to the laser driver 170, the pit 202P formed thereby becomes thicker and the reflectance is greatly reduced as shown in FIG. For this reason, the contrast ratio can be increased.

By the way, the parity data P1 to P4 and Q1 to Q4 are determined by the contents of the dot data Db0 as the subcode data D0 and the dot data Db1 to Db24 as the main data D1 to D24 and cannot be specified. Therefore, if the patterns of 6T to 10T are corrected so that the pits are narrowed as in the case of 3T and 4T, the pits formed in the slot periods of the parity data P1 to P4 and Q1 to Q4 are like white dots. It becomes possible to make it inconspicuous.
However, if a pattern with a positive pulse width of 5T occurs as parity data by chance, a thick pit is formed by the pattern, but the probability is not so high. Considered as a whole, it seems to be few. Similarly, since the probability that the 6T to 10T pattern appears is not so high, even if the strategy circuit 1563a does not correct the 6T to 10T pattern, it is considered that the influence on the image quality is small.
Further, since the 11T pattern is used for applications such as power control using the synchronization data Dframe as in the first embodiment, the strategy circuit 1563a does not correct the 11T pattern. 11T may be corrected so as to be narrowed.

In the second embodiment, if the dot data is $ D2, the dot white is specified, and if the dot data is $ 82, the dot black is specified. Other data can be used as long as the pattern has portions where “1” s are arranged at equal intervals.
Further, although the pit is narrowed for white dots and the pit is thickened for black dots, only one of the strategy circuits 1563a may be corrected.
As described above, in the second embodiment, it is possible to form an image on an optical disc in high quality and in a relatively short time without adding a hardware configuration to a configuration for recording data.

<Application of Second Embodiment>
In the first embodiment, since a part of the EFM waveform is extracted and supplied to the laser driver 170, the pit shape is not directly related to the dot data. For this reason, the pit interval cannot be defined by dot data. On the other hand, in the second embodiment, pits are directly defined by a pattern in which dot data is converted to 14 bits. For this reason, the pit interval can also be defined by dot data.

Here, when the pits are formed at intervals satisfying a certain condition, a diffraction phenomenon occurs for the following reason. FIG. 15 is a cross-sectional view of the optical disc 200 cut along the direction in which the pits 202P-1 and 202P-2 are formed. As shown in this figure, the pits 202P-1 and 202P-2 are formed so that the distance between the centers is d. On the other hand, visible light enters from the normal direction of the optical disc 200. Here, when the observer observes the recording surface of the optical disc 200 at an angle θ ₁ with respect to the normal direction, the optical path length from the pit 202P-1 to the observer, the optical path length from the pit 202P-2 to the observer, and Is an integer n times the observation wavelength λ, that is,
sin θ ₁ = nλ / d (1)
When the condition is satisfied, the phase of the observation light is aligned at the observation point, and as a result of strengthening each other, the observer visually recognizes the light of the wavelength as bright. On the other hand, when observing the recording surface of the optical disc 200 at an angle theta _2, when the optical path length difference between the pits 202P-1 and the pits 202P-2 is an odd m times the half of the observed wavelength lambda, i.e.,
sin θ ₂ = mλ / 2d (2)
When the condition is satisfied, the phase of the observation light is shifted by 180 degrees at the observation point and cancel each other. Therefore, the observer visually recognizes that the light having the wavelength is dark.

Therefore, in the second embodiment, when an appropriate dot data is selected and pits are formed at the interval d, the observer is bright when observing light of wavelength λ reflected by the pits at an angle θ _1. viewing and visually recognizes the dark when observed at an angle theta _2. For this reason, a kind of hologram effect can be given to the formed image.
In the case of the CAV method, since the interval between the dots (pits) increases from the inner circumference side to the outer circumference side of the optical disc 200, it is necessary to appropriately select dot data (14-bit pattern) in consideration of this point. is there.

In the first and second embodiments described above, the pits are formed along the pregroove by tracking control. However, the rotation of the optical disc 200 and the feeding of the pickup 130 are synchronized to form an image by this. Also good.
In the first and second embodiments, the CAV method with a constant angular velocity is used, but a CLV (Constant Linear Velocity) method with a constant linear velocity may be used. However, in the coordinate conversion, it is necessary to consider that the sectors are not aligned radially. Needless to say, as the optical disc 200, various types such as a DVD can be applied in addition to the CD-R.

1 is a block diagram showing a configuration of an entire system including an optical disc device according to a first embodiment of the present invention. It is a block diagram which shows the structure of an optical disk device. It is a block diagram which shows the structure of the write signal preparation device in an optical disk apparatus. It is a figure which shows the content of the interleaving in an optical disk device. It is a figure which shows the EFM frame etc. in an optical disk device. It is a timing chart which shows the relationship between rotation of a spindle motor, and various signals. It is a figure for demonstrating the dot of the image which should be formed in an optical disk. It is a flowchart which shows operation | movement of the host computer at the time of image formation. It is a figure which shows the functional block of the host computer at the time of image formation. It is a figure which shows the content of the deinterleaving process in a functional block. 4 is a timing chart showing an image forming operation in the optical disc apparatus. It is the elements on larger scale which show an example of the image formed with the same optical disk apparatus. It is a block diagram which shows the structure of the write signal preparation device of the optical disk apparatus which concerns on 2nd Embodiment of this invention. 4 is a timing chart showing an image forming operation in the optical disc apparatus. It is a figure for demonstrating the diffraction phenomenon in a hologram.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... System, 10 ... Host computer, 20 ... CPU (acquisition means, deinterleaving means), 100 ... Optical disk apparatus, 120 ... Main control part (change means), 130 ... Pick-up (pit formation means), 156 ... Write signal Creater, 200 ... optical disk, 1561 ... interleave unit, 1562 ... encoder (framing means), 1563 ... strategy circuit, 1565 ... discriminator (identification means), 1566 ... time axis extender, 1567 ... gate circuit (gate means)

Claims (1)

Dividing the recording area of the optical disc into a plurality of small areas defined in the polar coordinate system,
For each of the plurality of small regions, interleave dot data for specifying a ratio of the formation of pit rows every predetermined number,
For each of the areas, an optical disc device that forms a pit row at a rate according to the interleaved dot data,
A computer for supplying the dot data;
Conversion means for converting image data defined by an orthogonal coordinate system into the polar coordinate system;
When a small region continuous in the angular direction with the same diameter in the polar coordinate system is sectorized every predetermined number, a predetermined number of dot data included in the sector is acquired based on the image data converted in the polar coordinate system Acquisition means, and
A program that functions as a supply unit that rearranges an array of a predetermined number of dot data acquired by the acquisition unit and supplies the rearranged dot data to the optical disc apparatus.

Images