JPH01151073A - Optical disk device - Google Patents

Abstract

PURPOSE:To execute the large capacity of a recording capacity by recording and reproducing the data for 2 sectors with a two-fold data rate of an inner circumferential part to respective sectors of the outer circumferential part. CONSTITUTION:A recording circuit 2 and a reproducing circuit 4, when said sector is in the inner peripheral part, are selected by switches 8 and 10. Here, when the inner peripheral part and the outer peripheral part are specified on a recording and reproducing format beforehand and the sector is in the outer peripheral part, the switches 8 and 10 select and operate a recording circuit 7 and a reproducing circuit 9. The recording circuit 7 is operated at the double speed 14.8MBPS of the recording circuit 2 and writes a data 2,548 bytes with the double length. The reproducing circuit 9 reproduces and detects 2,548-bytes of data at a double data rate of 14.8MBPS at the time of data reproduction of the outer peripheral part. Thus, the recording capacity is increased as a whole.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an optical disc device for recording and reproducing PCM signals.

2. Description of the Related Art In recent years, magneto-optical disk devices have been actively developed as large-capacity data file devices capable of high-density recording and reproduction, and various devices have been developed.

Hereinafter, a conventional magneto-optical disk device as described above will be explained with reference to the drawings. FIG. 6 shows the configuration of a conventional magneto-optical disk device, FIG. 7 shows the recording/reproducing format on the disk, and FIG.
The figure shows the format of one sector.

In FIG. 6, 1 is a magneto-optical disk, 2 is a recording circuit,
3 is an access circuit, 4 is a reproduction circuit, 5 is an optical pickup, and 6 is a magnetic bias.

As shown in FIG. 7, the magneto-optical disk 1 has an effective recording and reproducing range with a radius of 3QN for a disk with a diameter of 5.26 inches.
Approximately 18000 recording/reproducing tracks are provided in this area in an area of 60 MM from IN, and each track is divided into 17 sectors.The disk is rotated at a constant angular velocity of 2400 RPM. As shown in FIG. 8, the format of each sector is divided into a 52-byte address section and a 1274-byte recording/reproduction data section. In the address section, address data is written as irregularities on the disk surface by 2/7 modulation following a sector mark indicating the beginning of the 'sector.

Similarly, 2/7 modulation is used for the modulation method of the recording/reproduction data section, and the data rate of both the address section and the data section is 4MBPS, and the clock frequency after 2/7 modulation is 14.8 MHz. Therefore, they are the same. The total recording capacity in this case is approximately 300 Mbytes. As shown in FIG. 6, the optical pickup 5 directs its optical output spot onto the magneto-optical disk 1. As shown in FIG. The access circuit 3 moves the optical spot position to an arbitrary track. The magnetic bias 8 applies a bias magnetic field to the magneto-optical disk 1 when erasing or recording data. Still, the recording circuit 2 outputs recording data to the corresponding sector at the same data rate as the address section to modulate the intensity of the light spot. During reproduction, the reproduction circuit 4 detects reproduction of data at the same data rate as that of the address section.

As described above, in the recording/reproducing format with constant angular velocity, the data rate is always constant, so reading and writing of data in the address part and data part can be performed smoothly, which also helps to speed up access.

Problems to be Solved by the Invention However, optical discs perform high-density recording in order to increase capacity, but in the above-mentioned recording and reproduction at a constant angular velocity, the recording density changes depending on the track, so the maximum recording density cannot be achieved. The overall sector format had to be matched to the sector format of the innermost periphery, and the recording density was lower and there were more whiteouts toward the outer periphery. Furthermore, in order to further increase the recording capacity, the format itself must be changed, such as increasing the number of sectors toward the outer periphery, which is extremely inconvenient in terms of standardization of optical discs.

In view of the above-mentioned problems, the present invention is designed to improve the overall data recording and reproduction by recording and reproducing twice the amount of data per sector in the inner periphery in the outer periphery sectors where the recording density is lower. An object of the present invention is to provide an optical disk device with a large recording capacity.

Means for Solving the Problems In order to achieve the above object, the present invention provides an optical disc in which each track is evenly divided into a plurality of sectors and a sector address is written at the beginning of each sector at a specific data rate, and a first recording means for recording data of a specific length in the corresponding sector at a data rate equal to the data rate; and a first recording means for recording data of a specific length in the corresponding sector at a data rate twice the data rate. a second recording means for recording data of approximately twice the length of the specific length; and a first recording means for reproducing the data when the corresponding sector is written by the first recording means. and a second reproducing means for reproducing the data when the corresponding sector is written by the second recording means. The recording means and the first reproducing means are used, and the second recording means and the second reproducing means are used for recording and reproducing in the outer peripheral sector.

According to the above structure, the present invention records and reproduces data at the same data rate as the address area in the inner area, and records and reproduces data for two sectors in one sector in the outer area at twice the data rate of the inner area. It will be recorded and played back.

EXAMPLE An example of the present invention will be described below with reference to the drawings.

FIG. 1 shows the basic configuration of an optical disc device according to an embodiment of the present invention, FIG. 2 is a detailed view of the main part of the recording circuit, and FIG. 3 is a detailed view of the main part of the reproducing circuit. FIG. 4 shows the recording/reproducing format of the magneto-optical disk, and FIG. 5 shows the sector format. Hereinafter, the same components as in the conventional example FIG. 6 will be indicated by the same reference numerals and the explanation of the drawings will be omitted.

In Figure 1, 7 is a data rate of 14.8 MBPS.
8 and 1o are the recording circuits for recording data.
9 is a switch that switches depending on the inner or outer position of the sector, and 9 is a data rate of 14.8MBP.
This is a reproducing circuit for reproducing data in S.

Regarding the magneto-optical disk device configured as above,
The operation will be explained below.

First, in FIG. 1, the recording circuit 2 and the reproducing circuit 4 are selected by the switches 8 and 10 when the corresponding sector is the inner circumferential portion, and perform the same recording and reproducing operation as in the conventional example described above. Here, as shown in FIG. 4, the inner circumferential part and the outer circumferential part are predetermined in the recording/reproducing format, and when the corresponding sector is the outer circumferential part, the switches 8 and 1o are connected to the recording circuit element and the reproducing circuit element. Select and operate 9. Recording circuit 7 operates at twice the speed of recording circuit 2, 14.8 MBPS, and writes data of 2548 bytes, which is twice the length. The reproduction circuit 9 reproduces and detects 2,548 bytes of data at a double data rate of 14° sMBPS when reproducing data from the outer circumference. The data format in this case is as shown in FIG.

Most of the recording circuits 2 and 7 described above, including the switch 8, can be made common as shown in FIG. Further, the reproducing circuits 4 and 9 can be similarly configured as shown in FIG.

In FIG. 2, the oscillator 11 outputs a clock with a frequency of 29.6 MHz, which is the clock frequency after 2/7 modulation at a data rate of 14.8 MBPS, and the divider 12 outputs a clock with a frequency of 29.6 MHz, which is the clock frequency after 2/7 modulation at a data rate of 14.8 MBPS. Divide the frequency by 2 to 14,8 MH
Outputs the clock of z. The buffer 16 temporarily stores one sector's worth of data when recording the inner circumference, and uses the control command of the control signal to temporarily store data for one sector. It outputs at a data rate of +7.4 MBPS or 14.8 MBPS, and when it is on the outer periphery, data for two sectors on the inner periphery is temporarily stored and output at a data rate of 14.8 MBPS. The switch 13 controls the modulation control section 14 and the buffer 1 according to the inner circumference and the outer circumference according to the control signal.
6 to 29, 6M)h or outputs a 14.8 MHz clock. The modulation control unit 14 modulates the output data of the buffer 16, adds a synchronization signal such as a data mark, and outputs it as write data. As described above, most of the recording circuits 2 and 7 in FIG. 1 can be made common.

In FIG. 3, the phase comparator 16 outputs the phase error between the input reproduction signal of the magneto-optical disk 1 and the reproduction clock output, and the low-pass filter 17 low-pass filters this phase error and outputs it. do. The voltage controlled oscillator 18 has a center frequency of 29.6
M) (where z is υ, outputs a signal that shows a frequency change proportional to the output of the low-pass filter 17. The frequency divider 19 divides the output of the voltage controlled oscillator 18 by 2 and outputs the divided signal. 2o
outputs the output of the frequency divider 19 as an output when the corresponding sector is the inner circumference, and outputs the output of the voltage controlled oscillator 18 as a recovered clock output when the sector is on the outer circumference. Therefore, phase comparator 16. Low-pass filter 17, voltage controlled oscillator 18.2 frequency divider 19. Phase synchronization section 21 with switch 2o
is configured, and clock recovery of the input signal is performed. The data determiner 22 punches out the input signal using the reproduced clock and outputs it. As described above, most of the reproduction circuits 4 and 9 in FIG. 1 can be made common.

As described above, according to this embodiment, the same recording and reproduction as in the conventional example can be performed in the inner circumference, and the same recording and reproduction as in the conventional example can be performed in the outer circumference.
This means that twice as much data can be recorded and reproduced. Therefore, for example, if the area less than 45 mm from the radius 3Qffff is defined as the inner circumference, and the area 60 mm from 45 mm is the outer circumference, the total recording capacity will be 45 mm compared to the conventional example of 300 M hide.
It can be increased up to 0MB. Further, it is possible to increase the capacity without making any changes to the format defined by the unevenness of the conventional optical disc itself. Furthermore, by applying the recording/reproducing means on the inner circumference to the outer circumference, it is possible to easily realize a device that is compatible with conventional optical disk devices.

Effects of the Invention The present invention aims to increase the recording capacity by recording and reproducing data for two sectors in each sector of the outer circumference at twice the data rate of the inner circumference, and further improves the recording capacity of the conventional optical disc. It is possible to provide an optical disc device that can be easily compatible with other devices.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of a magneto-optical disk device in two embodiments of the present invention, FIG. 2 is a detailed view of the main part of the recording circuit shown in FIG. 1, and FIG. 3 is a main part of the reproducing circuit shown in FIG. 1. Detailed drawing of the part,
4 is a diagram of the recording/reproducing format of FIG. 1, FIG. 5 is a diagram of its sector format, FIG. 6 is a block diagram showing the configuration of a conventional magneto-optical disk device, FIG. 7 is a diagram of its recording/reproducing format, and FIG. Figure 8 is a diagram of the sector format. 1... Magneto-optical disk, 2.7... Recording circuit, 3... Access circuit, 4, 9...
...Reproduction circuit, 5...Optical pickup, 6.
...Magnetic bias, 8゜10.13.20...
... Switch, 11 ... Oscillator, 12.19
...2 frequency divider, 14 ... modulation control section,
15... Buffer, 16... Phase comparator, 17... Low pass filter, 18... Voltage controlled oscillator, 21...・Phase synchronization section, 22...
...Data judger. Figure 2 Figure 3
21--Integrated Section Fig. 4 Fig. 5 Dectamark/--One-Optical Magnetism Dinuk 6-One-Ichi Party Science Big Asophi No. 6 Fig. 6--, Must Be High

Claims (3)

[Claims] (1) An optical disc in which each track is evenly divided into a plurality of sectors and a sector address is written at the beginning of each sector at a specific data rate; an access means for moving a light spot to an arbitrary track on the optical disc; a first recording means for recording data of a specific length in a sector at the same data rate as the data rate; and a first recording means for recording data of a specific length in a sector at a data rate twice the data rate; a second recording means for recording data of length, a first reproducing means for reproducing the data when the corresponding sector is written by the first recording means; a second reproducing means for reproducing the data when the data has been written by the recording means; the first recording means and the first reproducing means are used for recording and reproducing data in the inner sector; An optical disc device characterized in that recording and reproduction is performed using the second recording means and the second reproduction means in the outer peripheral sector. (2) The first recording means uses the operating clock of the second recording means divided by two, and the recording data format of the second recording means is such that the data format of the first recording means is repeated twice. 2. The optical disc device according to claim 1, wherein the first recording means and the second recording means have a common circuit. (3) The first reproducing means uses the operating clock of the second reproducing means divided by two, and the second reproducing means operates the first reproducing means at twice the speed. 2. The optical disc device according to claim 1, wherein the first reproducing means and the second reproducing means have a common circuit.