JPH0562358A - Optical disk and recording method thereof - Google Patents

Abstract

PURPOSE:To increase recording capacity per face by dividing the recording zone of an optical disk into two to ten recording zones for each recording track having inverse for a specific pitch and recording density. CONSTITUTION:The track pitch of the optical disk 10 is made narrower than 1.6mum, and the inverse of the line recording density of the recording track in the peripheral direction is specified at 1.0-0.7mum per a bit. And, the zone of the optical disk 10 is divided into plural tracks to provide recording zones, and the dividing number is made two to ten. Here, the total recording bits in the radius R of the optical disk 10 is indicated by the product of total recording bits per a sector multiplied by the number of sectors, and the inverse of the recording density in one track is indicated as a length required for one bit. Thus, the recording density of the track T2 in the outermost radius R2 against the track T1 of the innermost radius R1 in the recording zones is made the one required for above division. Consequently, the recording capacity per face is increased without reducing the access speed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disk which has a large storage capacity and is compatible with existing optical disks, and a recording method for the optical disk.

[0002]

2. Description of the Related Art Currently, the International Organization for Stannda for optical disks for data storage is used.
As a standard of rdization, there is an ISO / IEC DIS 10089 system for a 5.25-inch optical disc. In this standard system, the recording capacity of the optical disc is 326 Mbytes per side due to 1 Kbyte recording per sector.
512 bytes per sector records 293M per side
There is a recording capacity of bytes. This optical disc can handle a larger capacity than a magnetic disc as a recording medium for a computer or the like. In each parameter of this system, the track pitch is 1.6 μm and the reciprocal of the recording density in the circumferential direction is 1.0 μm / bit.

When used as a recording medium for a computer or the like, the access time required for recording / reproducing data must be short, that is, high speed. For this reason, the optical disk used in a computer or the like uses the CAV method that enables high-speed access.

[0004]

By the way, recently, computers have come to be able to handle a large amount of data at high speed. By effectively using the information processing ability of this computer, for example, while displaying a large amount of simulation results calculated by the computer on a display screen in real time, the data of the above result is recorded in a recording medium. There is. In order to make full use of the power of this computer in performing the above-mentioned processing, a recording medium having a larger recording capacity is required for the optical disc.

However, the CAV system used for this optical disc which enables high-speed access realizes the maximum recording density in the innermost circumference of the conventional optical disc.
Since the V recording method is set so that all tracks have the same recording capacity, the recording density on the outer peripheral side becomes lower than the recording density on the inner peripheral side. Therefore, the total storage capacity is CLV (Constant Linear Velocit) at a constant linear velocity.
y) It is less than the storage capacity of the method.

In view of the above situation, the present invention makes it possible to easily increase the recording capacity per surface without decreasing the access speed of the optical disk according to the new physical recording format, and the recording of the optical disk. It is intended to provide a method.

[0007]

In the optical disk according to the present invention, the pitch of the recording tracks recorded and formed on the optical disk is narrower than 1.6 μm, and the reciprocal of the linear recording density of the recording tracks in the circumferential direction is 1.0 to. The above problem is solved by setting the recording area of the optical disc to 0.7 μm / bit and providing a recording zone for dividing the recording area into a plurality of tracks and setting the number of the recording zones in the recording area to 2 to 10. To do.

Next, a method of recording data on an optical disk according to the present invention is a method of recording an optical disk in which a plurality of recording tracks are formed, in which the pitch of the recording tracks formed on the optical disk is narrower than 1.6 μm. , The reciprocal of the linear recording density of the recording track in the circumferential direction is 1.0 to 0.7 μ.
The above-described problem is solved by setting the recording area of the optical disc to m / bit and providing a recording zone for dividing the recording area into a plurality of tracks and setting the number of the recording zones in the recording area to 2 to 10.

[0009]

According to the optical disc and the optical disc recording method of the present invention, the linear recording densities in the divided tracks of the innermost recording zone and the outermost recording zone are made substantially equal to each other, and high-speed access is easily performed. be able to.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An optical disk and an optical disk recording method according to the present invention applied to a 5.25 inch will be described with reference to the drawings.

Conventionally, in the physical format of a 5.25-inch optical disc, each parameter of this system is set such that the track pitch is 1.6 μm and the reciprocal of the recording density in the circumferential direction is 1.0 μm / bit. The optical disc according to the present invention is the same as the conventional international standardization organization ISO / IEC 1008 in the physical format of a 5.25-inch optical disc.
The track pitch of the above optical disc is narrower than 1.6 μm from the standard 5.25 inch optical disc, and the reciprocal of the linear recording density of the recording track in the circumferential direction is 1.0 to 0.7 μm.
/ Bit, the recording area of the optical disc is divided into a plurality of tracks, and the number of the recording zones in the recording area is set to 2 to 10 for recording. Can be approximately equal to each other. By configuring and recording in this way, the optical disc has the same recording capacity per track in the same recording zone, and different recording capacities per track in different recording zones. The recording densities can be made substantially equal to each other. The recording capacity of a CAV type optical disc can be greatly increased (see FIG. 1).

The 5.25-inch optical disk of the present invention has to be changed in relation to the above parameters in order to improve the compatibility with the conventional 5.25-inch optical disk of the ISO / IEC 10089 standard of the International Organization for Standardization. The parameters are almost the same except the parameter that does not obtain.

The setting of each parameter of the continuous servo tracking method (CCS) of the ISO / IEC 10089 standard will be described while presenting numerical values as a concrete example. ISO /
The sector format of the optical disc 10 of the IEC 10089 standard is composed of an address portion of 52 bytes, a flag portion of 14 bytes, a data portion of 1274 bytes and a buffer portion of 20 bytes, which is a total of 1360 bytes. In the sector format configuration, the area ID for recording address information in the address section having 52 bytes is composed of 3 bytes. Further, when the area ID is subdivided, the area ID is 2 bytes as a track number,
The sector number consists of 1 byte and is recorded by 2-7 modulation.

The current 5.25-inch optical disk according to the ISO / IEC 10089 standard of the International Organization for Standardization has 3 per side.
There are 26 Mbytes and 293 Mbytes of optical disks. The number of sectors per recording track in each recording zone other than the innermost circumference of the optical disc of the present invention is set so that the recording densities are substantially equal to each other from the center of the optical disc to the inner radius and outer radius of each recording zone, as will be described later. It can be represented by the product of the ratio of the radii of and the original number of sectors.

The area ID is written three times in the address section together with the area CRC for recording the ID section error detection code. In this area ID, the maximum number of sectors per track in the existing two types of optical discs is described using 6 bits as the number of sectors up to 17/31. However, with the above format, the number of sectors is larger than 17/31, which is the number of sectors per track of the above-mentioned current two types of optical discs, and there are zones where 6 bits = 64 in the number of sectors is exceeded.
Therefore, in the sector number notation, for example, 2 bits of the notation of the ID field are eliminated, and 2 bits corresponding to this are used for the sector number notation to enable notation up to 8 bits = 256 in total.

As described above, although the area ID is partially changed, the area ID byte count of 52 bytes and the byte count per sector of 1360/746 bytes are not changed. Since the changed portion of the sector format of the optical disc 10 is limited to only the portion indicated by the number of sectors described above, the compatibility with the conventional optical disc can be easily obtained, and the manufacturing process can coexist in the production of the optical disc. This makes it possible to easily manufacture an optical disc.

First, in the optical disc and the optical disc recording method of the present invention, the recording area of the optical disc is changed from 2 to 10.
Dividing into recording zones will be described with reference to the schematic diagram shown in FIG. 1 as needed, regarding the principle of a specific physical format. The length of one track on the optical disk is represented by the length L of the circumference. Therefore, the length of one track of this optical disc varies depending on the radius R of the optical disc as shown by the equation (1) L = 2πR (1). The length of one track is, for example, 0th zero sector S ₀ to K−1th S in the radius R of the optical disc.
It is divided equally into _K-1 and K sectors.

Here, the total recording bit number M _R in the radius R of the optical disk is the total recording bit number m _R per sector.
And the number of sectors in one track, K, are represented by m _R K. Further, the recording density (reciprocal number) d of one track d
Is expressed as d = (2πR) / M _R (2) as a required length per bit.

Therefore, as shown in FIG.
Recording density in the track T ₂ of the outermost peripheral diameter R ₂ of the recording area with respect to the track T ₁ of the innermost diameter R ₁ of the recording area in 0, if the total number of bits per sector in each track are equal, the ratio R It decreases to ₁ / R ₂ . In order to suppress the loss at the outermost circumference diameter R ₂ , the number of sectors K ₂ within the outer circumference diameter is K ₂ ≈K ₁ × R ₂ / R ₁ (3) For K ₁ (R
_The recording density can be secured by multiplying by ₂ / R ₁ ).

However, it is apparent that the division of the data recording area increases the complexity of control such as switching control of the rotation speed of the spindle motor. To reduce this complexity, the recording region (R ₂ -R ₁₎ it is convenient to evenly min. That is, the recording area (R
₂ -R ₁₎ the zone number _{N (R 2 -R 1) /} N by evenly dividing.

Here, when the number of recording zones N = 2 and the number of sectors in the recording zone Z ₀ is K ₁ , the recording zone Z
Sector number K ₂ in _1, will be provided the boundaries of recording zone in an intermediate position (R ₂ -R ₁₎ / 2 of the innermost radius R ₁ and the outermost radius R _2, the relationship in equation (3) , K ₂ ≈K ₁ × (R ₂ + R ₁ ) / (2 × R ₁ ) (4) By setting the number of sectors K ₁ and K ₂ according to the zone areas in this way, the recording densities of the two areas can be made to be substantially the same value, and the recording capacity of the conventional data recording area can be limited to a limited data recording area. It becomes possible to secure a large recording capacity in comparison with the above.

In the number N of divided zones of the optical disk, the number N of recording zones is an integer of 2 or more. By the way, when the number of tracks in each recording zone is calculated by dividing the total number of tracks by the number N of recording zones, strictly speaking, a fraction may occur. In this case, it is advisable to adjust the fractional number of tracks in the outermost final zone.

The recording capacity of the optical disc according to the present invention is
The recording capacity tends to increase as the number N of recording zones increases. This tendency is shown in the graph of FIG. 2 in which the conventional recording capacity is standardized to 1 and the recording capacity ratio is increased. In FIG. 2, the number of sectors K of the optical disk actually takes only an integer value, but the value of the number of sectors K is set to a constant value by using the size of the optical disk, and the formula (4) is used. To obtain the recording capacity ratio. From the graph of FIG. 2, the number of recording zones is increased in the recording capacity ratio up to N = 2 to 10,
In particular, it can be seen that the recording capacity ratio is efficiently increased in the vicinity of the number of recording zones N = 2 to 5.

Further, in order to reduce the complexity caused by dividing the data area as described above, the optical disc 1
The recording area of 0 is divided into 2 ⁿ tracks (n is a natural number). By partitioning in this way, the recording area of the optical disc is divided into a plurality of recording zones every 2 ⁿ tracks, the storage capacities per track are equal in the same recording zone, and the recording per track is different in different recording zones. By making the capacities different, the linear recording densities of the respective recording zones can be made substantially equal to each other. Further, the discrimination signal ID of the optical disk 10 is convenient because it is used for a digital signal handled in binary units.

As a specific example, when the total number of tracks on the optical disk is, for example, 32768 tracks = 2 ¹⁵ , the number of tracks in one recording zone is 2 ¹³ (= 8).
192) Track address 15
The upper 2 bits of the bits can be used as they are as the zone address. The recording area of each data at the time of 4-division can always be checked by the zone address of the upper 2 bits, and the control becomes easy. However, since the total number of tracks is not normally 2 ⁿ tracks, some fractional tracks occur. This fractional track is dealt with by including it in the last recording zone for adjustment.

The number N of divided zones of the optical disk 10
Can be divided by various values depending on the track pitch TP and the data recording area width R _DB , as described above. Here, this relationship will be described. The total number of tracks TN in the data recording area is TN = R _DB / TP (5) As described above, the width R _B of each recording zone is 2 ⁿ
If the recording zone number N (N = 0, 1, 2, ..., N-1) is set by dividing each track, the total number of tracks TN is the number of 2 ⁿ tracks included in one zone. It is expressed as the divided quotient, or R _DB / R _B.

Further, the number of tracks outermost end zone Z _N-1 is expressed by the sum of the surplus when A is divided by 2 ⁿ tracks and the total number of tracks TN by 2 ⁿ tracks.

Here, the recording density (reciprocal number) d ₁ of the innermost circumference
Is represented by a value obtained by dividing the circumference of the innermost radius R ₁ , that is, 2πR ₁ by the product of the total number of bits per sector and the number of sectors K ₁ per track. In addition, the m-th optical disc (m
, 1, 2, ..., N-1, N), the radius R _m of the boundary position between the recording zone Z _m-1 and the previous recording zone is included in one recording zone at the innermost radius R _1. It is indicated by a value obtained by adding the product of 2 ⁿ tracks, the track pitch TP, and the number of recording zones (m-1).

A value larger than (the reciprocal of) the recording density d ₁ of the innermost circumference in the _m- th recording zone Z _m-1 of the optical disc obtained by dividing the data recording area into the number N of zones in this way, in other words, the innermost circumference. Maximum number of sectors that does not exceed the recording density of K
_m is represented by a quotient obtained by dividing the recording density of a recording track having a radius R _m from the center of the optical disk by the product of the total number of bits per sector. When this relationship is arranged, K _m = K ₁ × (R _m / R ₁ ) (6)

Using the above symbols, the total recording capacity gradually increases as the number N of recording zones increases (the number of n bits indicating the number of tracks decreases). Therefore, the total recordable capacity is the maximum number of sectors K _m of the _m- th recording zone Z _m-1.
And the recording capacity in one sector and the product of the number of tracks in the recording zone 2 ⁿ , the sum of m = 1 to N, the maximum number of sectors K _{N in} the final recording zone Z _N-1 and the recording capacity in one sector. And the total number of tracks TN divided by the number of tracks every 2 ^n, and the product of the number of surplus tracks.

In this optical disk 10, the track pitch TP is set to 1.6 μm. The relationship between the relative tracking signal amount and the track pitch TP has the relationship shown in FIG. 3 at the laser wavelength λ = 780 nm. Here, when the relative tracking signal amount of about 0.5 or more is adopted as the standard for the optical disc, it is understood that the track pitch TP of 1.3 μm or more is in a range suitable for general use.

FIG. 4 shows the relationship between the recording density and the error rate. The relationship between the recording density and the error rate shown in FIG. 4 is as follows: current laser wavelength λ = 780 nm, data
7 shows the case of the condition of 7 modulation. Under this condition, a bit length of 0.7 μm or more can maintain the error rate of 10 ⁻⁵ , so that it is set as an appropriate recording density.

An optical disk as a recording medium and a recording method shown in FIG. 5 will be described by way of a more specific example using the above principle. ISO standard ISO / IEC DI mentioned above
The S10089 5.25-inch optical disc has a radius R = 3
Track pitch is 1.4μ with 0-60mm as recording area
It is composed of m. Therefore, the total number of tracks having the recording area width of 30 mm is 21,428.

In this embodiment, the optical disk 20 has the number of recording zones N = 5, and the number of tracks per recording zone is divided into 4096 (= 2 ¹² ) tracks. The boundary radius R ₂ between the first zone Z ₀ and the second zone Z ₁ is
Since the radius R ₁ = 30 mm, the first boundary is calculated at R ₂ = 30 + 2 ¹² × 1.4 μm = 35.734 mm.

The divided optical disc 20 has a maximum recording density of 0.825 μm in the innermost recording zone Z ₀ .
The number of sectors per track, which corresponds to the division in the circumferential direction in m / bit, is set to K ₁ = 21 sectors. Also,
It can be seen from the equation (6) that the number of sectors K ₂ per track in the outermost recording zone Z ₄ is K ₂ = 21 × (35.7 / 30) = 25 sectors.

The disk diameter range indicating the boundaries of each recording zone, the number of tracks, and the number of sectors have the values shown in Table 1.
The number of tracks in the outermost recording zone Z ₄ shown in Table 1 is 4
It is shown by adding up the fractional number of tracks when equally divided for each 096 tracks.

[0037]

[Table 1]

The optical disc 20 divided even when 512 bytes are used per sector has the innermost zone Z.
_{At 0} , the reciprocal of the maximum recording density is set to 0.817 μm / bit, and the number of sectors per track corresponding to the pitch in the circumferential direction is set to K ₁ = 38 sectors, and the above parameters are calculated in the same relationship as above. To be done. The respective parameters are shown in Table 2. In this case, the number of sectors exceeds 2 ⁶ = 64. Therefore, the number of sectors is expressed as 8 bits = 25
6 is set to correspond to this.

[0039]

[Table 2]

The total recording bit number m _R per sector is 1
When K bytes = 1024 bytes and 512 bytes, respectively, the recording capacity of the current optical disc is 326 Mbytes, 644 Mbytes, and 293 Mbytes.
The number of bytes is 588 Mbytes, which is approximately twice the current recording capacity.

The optical disk according to the present invention is not limited to the above-mentioned case, and various modifications can be considered and set according to the track pitch, the recording density in the circumferential direction and the value of the number of zones. .. For example, the track pitch TP is set to 1.3 μm, and the other parameters are the same as in the above-described embodiment, and the number of sectors in the recording zones Z _{0 to} Z ₄ on the innermost side is K ₁ = 21, K ₂ = 25, respectively. K ₃ = 2
8, K ₄ = 32 and K ₅ = 36, the total recording capacity of this recording medium is 6 with a capacity of 1 Kbyte per sector.
It can be 92 Mbytes. The reciprocal of the maximum recording density at this time is 0.816 μm / bit.

Furthermore, the track pitch TP is set to 1.3 μm.
m and the recording capacity is 644 Mbytes similar to the above case, the maximum recording density is 0.87 μm / bit. In this case, the number of sectors is K ₁ = 1 in order.
9, K ₂ = 23, K ₃ = 26, K ₄ = 30 and K ₅ = 3
4. By increasing the number N of zones in this way, it is possible to increase the recording capacity.

The maximum recording density in the recording zone Z ₀ is 1.02 μm / bit when expressed by the reciprocal of the recording density. Similarly, the maximum recording density in the recording zone Z ₀ is 1.04 μm / bit when expressed by the reciprocal of the recording density. The number of bits in the sector having the maximum recording density is 1360 × 8 bits.

If 1 Kbyte can be recorded in one sector by dividing the optical disk into recording zones as described above, the data recording capacity is the same as that of the conventional ISO / IEC DIS 1008.
9 Amount of data in the standard of 326M bytes is 402
It can be increased to M bytes. By the method described above, the number of zones divided into 2 ⁿ tracks can be arbitrarily selected as the number of bits n, and the switching point of each divided recording zone can be switched by a power of 2 of the number of tracks. Therefore, when a digital discrimination signal is used, switching can be performed with, for example, the upper few bits. As described above, it is possible to enable large-capacity recording with an easy technique.

Further, a recording method for recording data on the optical disc will be described with reference to FIGS. 6 to 8.
FIG. 8 shows that when recording is performed by using the optical modulation method and the mark length recording method, the width t between the zero cross points with respect to the recording data read waveform is changed by the laser power during recording or the magnitude of the external magnetic field. By changing according to the power or the magnitude of the external magnetic field, for example, when a power larger than the normal strength is applied, the width t _S between the zero cross points from the rising edge to the falling edge is larger than t (t <t _S ), And this may appear as jitter.

On the other hand, in the case of the light modulation method, the jitter can be suppressed by using the pit position recording method. This will be explained with reference to FIG. 6A.
In the recording data shown in (1), "0" is always inserted between the recording data "1" (see the recording waveform of FIG. 6B). At the time of recording, optical modulation can be performed with the position of duty 50% of the recording data “1” in the recording waveform shown in FIG. 6B as the center position.

By recording in this way, when the peak position of the read waveform of the recording data at the time of reading shown in FIG. 6C is detected, the width t _S that fluctuates depending on the laser power at the time of recording or the magnitude of the external magnetic field. Is the width t _S between the zero-cross points from the rising edge to the falling edge shown in FIG. 8C.
Width t between peak positions without depending on fluctuations such as
(T = t _S ), and the same waveform as that shown in FIG. 6B can be output to solve the occurrence of jitter.

When the magnetic field modulation method is adopted,
Mark length (or edge) recording is preferred. this is,
The recording waveform shown in FIG. 7B is generated by inverting the previous level (mark length recording) in response to the level change from “0” to “1” of the recording data shown in FIG. 7A. Magnetic field modulation is a method of changing the timing of rising and falling of a waveform according to the strength of magnetism. Therefore, in this magnetic field modulation, a phase shift occurs when the magnetic field strength changes, but the width t _S between the zero cross points is the same as the mark length (width between edges) t according to the recording data. Can be recorded in width.

By thus recording, focusing on the rising and falling edges of the read waveform of the recording data at the time of reading shown in FIG. 7C, it depends on the laser power at the time of recording or the magnitude of the external magnetic field. The variable width t _S between the zero-cross points can be output in the same width (t = t _S ) as the mark length (width between edges) t according to the recording data,
It is possible to solve the occurrence of jitter.

As described above, in the recording method, the occurrence of jitter can be solved by using either the pit position recording and the optical modulation method or the edge recording and the optical modulation method.

FIG. 9 is a schematic block diagram of a drive device for recording and / or reproducing via the optical disc of the present invention. A sector switching signal designated by the user, for example, is supplied to the synthesizer unit 11 via the input terminal 10. The sector switching signal is I indicating each recording zone.
It is a signal indicating whether the D signal or the optical disk 14 is an optical disk configured in the physical format of the present invention or an optical disk configured in the current physical format. As the data for discriminating the type of the optical disc, for example, information about the type of the disc is written in a phase encoding unit (PFP) at the innermost circumference of the optical disc in a so-called bar code. The sector switching signal is generated using this data.

A reference clock corresponding to the sector switching signal is supplied to the synthesizer section 11 via the input terminal 12. The synthesizer unit 11 modulates recording data to be supplied to the laser driver unit 13 and the optical disc 14 for controlling the driving of the laser beam, respectively, by using the sector switching signal and the control signal generated by the reference clock, and from the optical disc 14. Of the optical signal from the modulation / demodulation circuit section 15 and the optical disk 14 for demodulating the reproduction data of the optical system 1.
The signal is supplied to an RF signal processing circuit 17 that processes the signal converted into the RF signal in 6 and a phase lock loop (PLL) circuit 18 for locking the phase.

Further, the modulation / demodulation circuit section 15 is subjected to data modulation in accordance with data and control signals supplied from a controller section (not shown) via the input terminal 19 and supplied to the laser driver section 13. .. The laser driver unit 13 emits laser light and writes data on the optical disc 14 via the optical system 16. At this time, the optical disc 1
The laser intensity emitted is adjusted according to the return light reflected by the surface No. 4, and the return light is supplied to the servo circuit 20 to servo-control the position and the like of the optical system 16.

The laser beam reflected by the optical disk during data reproduction is converted into an RF signal by the optical system 16. This output signal is supplied to the RF signal processing circuit 17. The RF signal is, for example, binarized in accordance with the control signal supplied from the synthesizer unit 11, waveform equalization processing is performed, and the RF signal is sent to the PLL circuit 18. This PL
The L circuit 18 is also controlled according to the control signal supplied from the synthesizer section 11. The binarized reproduction signal output from the PLL circuit 18 is the modulation / demodulation unit 1 described above.
Send to 5. The modulator / demodulator 15 demodulates the reproduced signal and outputs it from the output terminal 21 to a controller (not shown).
Output to.

In this way, the control signal corresponding to the number of sectors of the optical disk 14 is generated by the synthesizer section 11 and supplied to each section, whereby the optical disk subjected to the physical format of the present invention and the current physical format. It is possible to easily provide a drive device that is compatible with both of the optical discs that have been subjected to. This drive device can reduce the confusion of users due to the difference in the physical format of the optical disc, and thus grow the market of the larger optical disc drive.

[0056]

As is apparent from the above description, according to the optical disc and the recording method for the optical disc of the present invention, the pitch of the recording tracks recorded and formed on the optical disc is 1.
The reciprocal of the linear recording density of the recording track in the circumferential direction is set to 1.0 to 0.7 μm / bit, and a recording zone for dividing the recording area of the optical disk into a plurality of tracks is provided to set the recording area in the recording area. By recording the number of recording zones from 2 to 10, an optical disc having a larger capacity than that of the existing recording medium can be realized and recording can be performed.

Also, there are few changes in the manufacture of the optical disc, the coexistence of the manufacturing steps can be achieved, and the manufacturing can be easily performed. By maintaining compatibility in this way, it is possible to reduce confusion among users of the existing optical discs, and it is possible to supply a drive device that drives a large-capacity recording medium to the market.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing the principle of an optical disc and a recording method for an optical disc according to the present invention.

2 is a graph showing the relationship between the number of divided recording zones and the recording capacity ratio of the optical disc in FIG.

FIG. 3 is a graph showing a relationship between a track pitch of an optical disc and a relative tracking signal amount.

FIG. 4 is a graph showing the relationship between the recording density of an optical disc and the error rate.

FIG. 5 is a schematic view showing an embodiment in which the optical disc according to the present invention is applied to a 5.25-inch optical disc.

FIG. 6 is a diagram illustrating a recording method of recording on an optical disc by using an optical modulation method and pit position recording.

FIG. 7 is a diagram illustrating a recording method for recording on an optical disk by using a magnetic field modulation method and mark length (or edge) recording.

FIG. 8 is a diagram illustrating a recording method for recording on a conventional optical disc by using an optical modulation method and mark length recording.

FIG. 9 is a schematic block diagram of a drive device that drives both the optical disc of the present invention and a current optical disc.

[Explanation of symbols]

N ・ ・ ・ ・ ・ ・ ・ ・ Number of recording zones 2 ⁿ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Number of tracks included in one recording zone R ₁・ ・ ・ ・ ・ ・・ ・ ・ Radius of innermost circumference of recording area R ₂・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Radius of outermost circumference of recording area K ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Number of sectors TP ・・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Track pitch

Claims (2)

[Claims] 1. The pitch of recording tracks formed on an optical disc is narrower than 1.6 μm, and the reciprocal of the linear recording density of the recording tracks in the circumferential direction is 1.0 to.
An optical disc having a recording area of 0.7 μm / bit, the recording zone of the optical disc being divided into a plurality of tracks, and the number of the recording zones in the recording area is 2 to 10. 2. A recording method for an optical disc having a plurality of recording tracks formed therein, wherein the pitch of the recording tracks formed on the optical disc is narrower than 1.6 μm, and the reciprocal of the linear recording density of the recording tracks in the circumferential direction is calculated. 1.0 ~
A recording method of an optical disc, wherein the recording region of the optical disc is 0.7 μm / bit, and the recording region is divided into a plurality of tracks, and the number of the recording zones in the recording region is set to 2 to 10.