KR20040023086A - High density read only optical disc, and apparatus and method for reproducing a data recorded on them - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high-density reproduction-only optical disc, and an optical disc apparatus and method according thereto, wherein data stored in a lead-in area of a high-density reproduction-only optical disc such as a BD (Blu-ray Disc) -ROM or the like is stored in a BD-RW or the like. By recording in a pre-pit row of shapes associated with high frequency modulated (HFM) grooves applied to the same high-density rewritable optical disc, the desired information can be recorded, but the same single high-density reproducing optical disc or high-density rewritable It is a very useful invention that the same single tracking servo operation can be continuously performed for the entire area of the optical disc, thereby effectively preventing complicated algorithms for controlling a plurality of tracking servos and the enlargement of the device accordingly.

Description

High density read only optical disc, and apparatus and method for reproducing a data recorded on them}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disc for high-density reproduction in which a large amount of video and audio data is recorded and stored, and an optical disc apparatus and method accordingly.

Recently, a new high-density rewritable optical disc capable of recording and storing high-definition video data and high-quality audio data for a long time, for example, a rewritable Blu-ray Disc (hereinafter referred to as BD-RW) as shown in FIG. As the standardization of.) Progresses rapidly, related products are expected to be developed, released and commercialized.

On the other hand, in the case of the BD-RW as described above, the clamping area, the transition area, the BCA area, and the lead-in area are present in the inner circumferential surface of the disk, and the data is located on the center and outer circumferential surfaces of the disk. The disk structure includes a data area and a lead-out area, respectively.

The lead-in area may include a first guard (Guard 1) area and a permanent information & control data (PIC) area, a second guard (guard 2) area, an information 2 (Info 2) area, and an OPC (Optimum) area. Power control) area and the like, the first guard area and the PIC area are a pre-recorded area in which data is pre-recorded, whereas the remaining lead-in area and the data The area and the lead-out area are areas where new data is rewritten.

In the PIC area, a high frequency modulated (HFM) groove is formed and recorded as the area where the main general information of the disk to be permanently stored is recorded. The HFM groove is shown in FIG. As described above, the data is modulated and recorded by a Bi-Phase Modulated method to record and store disk information.

For example, when HFM grooves of the same phase are recorded during the recording section of '36T', the value is '0', and when HFM grooves of different phases are recorded during the recording section of '36T'. , The value is '1'.

On the other hand, the tracking servo for tracking the HFM groove recorded in the PIC region as described above is to use a well-known push / pull method, for this purpose, as shown in FIG. A two-divided light receiving element 12 for photoelectrically converting light received through the objective lens 10 and the collimated lens 11 into an electrical signal, and an electrical signal Ea, which is photoelectrically converted by the two-divided light receiving element, respectively; And a differential amplifier 13 for differentially amplifying Eb).

Accordingly, in the optical disk device, a tracking servo operation on the HFM groove is performed with reference to a tracking error signal (TE = Ea-Eb) output through the differential amplifier. For the wobble-shaped groove to be recorded, a tracking servo operation is performed on the wobble-shaped groove with reference to the tracking error signal TE = Ea-Eb output through the differential amplifier.

On the other hand, in the case of the high-density playback-only optical disc, for example, BD-ROM, which is currently discussed among related companies with the development of the BD-RW, as shown in FIG. And a disc structure in which a data area and a lead-out area exist respectively on the center plane and the outer circumferential surface of the disc, and in the lead-in area, disc information is recorded in the HFM groove manner as in a BD-RW. The data area and lead-out area also have a disk structure in which data of pre-pit columns are recorded and stored as in a conventional CD-ROM or DVD-ROM or the like.

However, if the disc information is recorded in the lead-in area of the BD-ROM under discussion in the HFM manner as in the BD-RW, a push-pull tracking servo for the tracking servo of the HFM groove is required. Differential phase detection (DPD) tracking servos for tracking servos of the pre-pit rows recorded in the data area and the lead-out area are both required at the same time.

In addition, when only the HFM groove is present in the lead-in area and no pre-pit shaped data is recorded, the operation of the PLL circuit using the RF signal cannot be performed, and connection reproduction between the lead-in area and the data area is prevented. The problem of disconnection occurs.

As a result, as shown in FIG. 5, the optical disk apparatus includes a quadrature light receiving element 22 for photoelectric conversion of light received through the objective lens 20 and the collimating lens 21 into an electrical signal, and A plurality of phase detectors 26 for detecting the phases of the photoelectrically converted electrical signals Ea, Eb, Ec, and Ed through the four-segmented light receiving elements, and then amplify and differentially amplify the electrical signals of the detected phases. 26, 27, 29, first and second summing amplifiers 23 and 24, and differential amplifier 25 are required, as well as for the same BD-ROM inserted and seated in the optical disc device. Since the tracking servo operation, that is, the push-pull tracking servo operation and the DPD tracking servo operation, must be performed separately, a complicated algorithm for controlling a plurality of tracking servos is necessary, and the device becomes large in size. This will occur.

Accordingly, the present invention was devised to solve the above problems, and pre-pit (Pre-shaped) having data associated with the HFM groove is recorded and stored in the lead-in area of an optical disc for high-density reproduction such as a BD-ROM. A high-density reproducing optical disc and an optical disc according to which the same tracking servo operation can be continuously performed for the entire area of the same single high-density reproducing optical disc or the high-density rewritable optical disc It is an object of the present invention to provide an apparatus and method.

1 shows a disc structure for a general rewritable optical disc (BD-RW),

FIG. 2 shows the shape of an HFM groove modulated and recorded in the lead-in area of a general rewritable optical disc.

FIG. 3 illustrates a configuration of a push / pull tracking servo applied to a general rewritable optical disk device.

Fig. 4 shows an embodiment of a disc structure for a typical high density reproduction-only optical disc (BD-ROM).

FIG. 5 illustrates a configuration of a tracking servo of a DPD method applied to a general optical disk device.

Fig. 6 shows an embodiment of a disc structure for a high density reproduction-only optical disc (BD-ROM) according to the present invention.

FIG. 7 shows the shapes of pre-pit rows recorded in the lead-in area of the high-density reproduction-only optical disc (BD-ROM) according to the present invention.

8 illustrates a configuration of a tracking servo of a push-pull type and a dipid type method applied to an optical disk apparatus and method according to the present invention.

9 to 11 show wobble-shaped spaces and marks formed in the PIC area of the high-density reproduction-only optical disc (BD-ROM) according to the embodiment of the present invention.

※ Explanation of code for main part of drawing

10, 20, 50: objective lens 11, 21, 51: collimated lens

12,22,52: Light receiving element 13,25,55,65: Differential amplifier

23,24,30,31,53,54,63,64: summing amplifier

26,27,28,29,57,58,59,60: phase detector

An optical disc for high-density reproduction according to the present invention for achieving the above object is a high-density reproduction-only optical disc including a lead-in area, a data area, and a lead-out area. Pit rows having a recording pattern of a modulated bi-phase groove (Bi-phase groove) are recorded and formed within the same level section of the high-frequency modulated bi-phase groove, the space and the mark or the mark and the space of the mark. The sum is repeatedly recorded as odd (2n + 1) pieces.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of an optical disc for high-density reproduction and an optical disc apparatus and method according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 6 shows an embodiment of a disc structure for an optical disc for high-density reproduction according to the present invention. In the case of the optical disc for high-density reproduction, for example, a BD-ROM (Blu-ray Disc-ROM), FIG. As described above, a clamping area and a lead-in area exist on the inner circumferential surface of the disk, and a data area and a lead-out area on the center and outer circumferential surfaces of the disk. Out Area) each have a disk structure,

On the other hand, in the data area and the lead-out area, pre-pit row data is recorded and stored as in a conventional CD-ROM or DVD-ROM, and the lead-in area is a PIC area of the lead-in area of the BD-RW. Pre-pitched data of a shape similar to the HFM groove previously recorded in the recording is recorded and stored.

That is, in the lead-in area, data of pre-pit rows are recorded as in the data area and lead-out area, and in the optical disc device for reproducing the same, for the same BD-ROM entire area inserted and seated in the device, DPD tracking servo control operation can be applied collectively.

On the other hand, in the shape of the pre-pit rows recorded in the lead-in area, as shown in Fig. 7, the pit rows are continuously recorded on the same track line during a predetermined recording period, or the pit rows are the same track during the predetermined recording period. Are discontinuously recorded at different locations within.

For example, as shown in FIG. 7, when a data sequence having a value of '0101' is recorded in the lead-in area, a total of 36T sections in which six 3T pit rows are continuously recorded on the same track line ('0') and a total of 36T sections ('1') in which three 3T pit rows are discontinuously recorded at different positions in the same track, respectively. That is, the same information recording recorded by the HFM method while being arranged in the pre-pit rows as described above is possible.

On the other hand, the reflected light reflected by the pit rows continuously or discontinuously recorded in the lead-in area as described above is photoelectrically converted by a quadrature light-receiving element (not shown) applied to a conventional servo servo of DPD method. The photoelectrically converted electric signals Ea, Eb, Ec, and Ed are, as shown in FIG. 7, a plurality of phase amplifiers 33, 34, 35, 36 and first and second summation amplifiers 30, 31. And the differential amplifier 32, a DPD tracking error signal (TE = (Ea + Ec)-(Eb + Ed)) is finally detected and output from the differential amplifier.

Accordingly, in the lead-in area, the DPD tracking servo operation can be performed by the pre-pit, and the recorded data sequence of '0101' can be detected and decoded by filtering the DPD signal according to the corresponding frequency. In the optical disk device, only the tracking servo operation of the DPD method is successively performed, so that the tracking servo operation for the entire area of the same BD-ROM can be normally performed, and the same information as the disk information recorded by the HFM method is recorded. This allows the same PLL operation to be performed from the lead-in area.

On the other hand, the length of each pit formed and recorded in the lead-in area as described above may have the same pit length, and may be formed and recorded in various kinds of pit lengths, for example, two or three kinds of pit lengths. have.

Further, by using a unique shape in which the pit rows are formed and recorded, other information can be expressed, and the depth of the pit is deeper or shallower than 'λ / 4' where the push-pull signal is detected small. For example, in the case of a BD-ROM, the depth of the pit is formed and recorded as' 3λ / 4 ', and in the case of a BD-RW, the pit depth of the lead-in area and the pit depth of the data area are respectively' λ. / 8 'and' λ / 4 'may be recorded differently.

The pit string may use a modulation code method used in the data area, and the modulation code may be used continuously or in combination by selecting any one of '3T', '2T', or a predetermined length. In addition, different data may be additionally recorded in each pit.

On the other hand, in the optical disk apparatus according to the present invention, when any one of the BD-RW or BD-ROM is inserted and seated in the apparatus, the tracking servo operation corresponding to the optical disk can be selectively performed. As shown in FIG. 5, the objective lens 50, the collimating lens 51, the quadrature light receiving element 52, and the plurality of summation amplifiers 53, 54, 63, 64 and the differential amplifiers 55, 65, And the selection switch 56 may be included, which will be described in detail as follows.

First, when the optical disc of any one of the BD-RW or the BD-ROM is inserted and seated in the optical disc device, the reflected light received through the objective lens 50 and the collimated lens 51 is divided into the four light receiving elements 52. Photoelectric conversion of the photoelectrically converted electric signals Ea, Eb, Ec, and Ed by the first and second summation amplifiers 53 and 54 and the first differential amplifier 55. The detection signal is output as an error signal TE_DPD = (Ea + Ec)-(Eb + Ed).

In addition, the electrical signals Ea, Eb, Ec, and Ed that are photoelectrically converted by the four-segment light-receiving element 52 may be formed by the third and fourth summation amplifiers 63 and 64 and the second differential amplifier 65. The tracking error signal TE_P / P = (Ea + Eb)-(Ec + Ed) of the push-pull method is detected and output.

Meanwhile, in a micom (not shown) or a servo controller (not shown) included in the optical disk device, when the type of the optical disk inserted and seated in the device is a BD-ROM, the selection switch 56 Operation control, so that the DPD tracking error signal TE_DPD detected and output from the first differential amplifier 55 is selectively outputted, and when the type of the optical disc inserted and seated in the device is BD-RW, the selection is performed. By operating the switch 56, the push-pull tracking error signal TE_P / P detected and output from the second differential amplifier 65 is selectively outputted.

Accordingly, in the case of the BD-RW, the push-pull tracking servo operation is normally performed. In addition, in the case of the BD-ROM, the tracking servo operation of the DPD method can be controlled.

For reference, when the BD-ROM-only reproduction optical disc device is developed and released, only the DPD tracking servo operation can be used as described above.

On the other hand, in order to more accurately decode the main general information of the disc permanently recorded in the PIC area of the read-in Blu-ray disc (BD-ROM), a wobble type space repeatedly recorded in the PIC area ( Space and Mark, or the push-pull signal detected by the mark and space should be detected continuously without disconnection. This will be described in detail below.

First, in the PIC region of a reproduction-only Blu-ray disc (BD-ROM) according to the present invention, main general information of the disc is a pit row having a recording pattern of a high-frequency modulated bi-phase groove (Bi-phase modulated HFM groove). Record is formed.

In addition, when HFM grooves of the same phase are recorded during the recording section of '36T', the value is '0', and when HFM grooves of different phases are recorded during the recording section of '36T', The value becomes '1', in which a space and a mark or a sum of marks and spaces are repeatedly recorded by an odd number (2n + 1) in the same level section of the high frequency modulated bi-phase groove.

For example, as shown in FIG. 9, in the high level '18T' recording section corresponding to 'Data 1', the space 6Ts, the mark 6Tm, and the space 6Ts of 6T length are sequentially repeated. In addition, in the low level '18T' recording section, the 6T-long mark 6Tm, the space 6Ts, and the mark 6Tm are sequentially recorded repeatedly.

That is, in the '18T' recording section, spaces and marks having a predetermined length or marks and spaces are repeatedly recorded in sequence, in which case the spaces and marks or marks and spaces repeatedly recorded in the high and low level recording sections are recorded. The sum of the numbers is three, that is, odd numbers, and a space or a mark is recorded at the beginning and the end of the recording section, respectively.

In addition, in the high-level '36T' recording section corresponding to 'Data 0', the space 4Ts and marks 4Tm having a length of 4T are sequentially recorded and repeated, and 4T in the low-level '36T' recording section. The mark 4Tm and the space 4Ts of the length are repeatedly recorded in sequence.

That is, in the '36T' recording section, spaces and marks having a predetermined length or marks and spaces are repeatedly recorded sequentially, in which case the spaces and marks or marks and spaces repeatedly recorded in the high and low level recording sections are recorded. The sum is 9, that is, odd numbers, and spaces or marks are recorded at the beginning and the end of the recording section, respectively.

Meanwhile, spaces and marks are recorded to the left and right at low level transition points of the high frequency modulated bi-phase groove, and marks and spaces are recorded to the left and right at high level transition points. For example, as shown in FIG. 9, a 6T long space (6Ts) is located at a level transition point from a high level '18T' recording section corresponding to 'Data 1' to a low level '18T' recording section. And mark 6Tm are recorded from side to side, respectively, and at the level transition point from the low level '18T' recording section to the high level '36T' recording section, 6Tm long marks 6Tm and 4T long spaces ( 4Ts) are recorded from side to side, respectively.

And. At the level transition point from the high level '36T' recording section to the low level '36T' recording section, a space of 4T length 4Ts and a mark 4Tm 4T long are written left and right, respectively, and the level transition Minimizing the disconnection of the push-pull signal detected at the point.

On the other hand, as shown in Fig. 10, a 6T-length mark 6Tm and a space at a level transition point from a high level '18T' recording section corresponding to 'Data 1' to a low level '18T' recording section. 6Ts are recorded left and right, respectively, and at the level transition point from the low level '18T' recording section to the high level '36T' recording section, a 6T long space 6Ts and a 4T long mark 4Tm Are recorded from side to side, the disconnection occurs in the push-pull signal detected at the level transition point, and the correct decoding operation cannot be achieved.

On the other hand, in order to more accurately detect the push-pull signal detected by the above-described wobble-shaped spaces and marks from the RF signal detected by the general pit column data, the frequency of the push-pull signal is applied to the general data. Since it is advantageous to be farther away than the frequency of the RF signal, it is desirable to record the pit length of the space or mark as short as possible, for example '2T' length or '3T' length.

In addition, for accuracy of tracking servo, the digital sum component (DSV: Digital Sum Value) is set to zero space and mark or the pit length of the mark and space recorded in the same level section of the high frequency modulated bi-phase groove. Zero) or setting recording to have a minimum value is preferable.

For example, as shown in FIG. 11, the space 6Ts, the marks 6Tm, and the spaces 6Ts having a length of 6T are sequentially recorded in a high level '18T' recording section corresponding to 'Data 1'. In this case, the digital sum component (DSV) becomes '+6' based on the conventional DSV calculation formula, but the space (2Ts, 3Ts) and the mark (2Tm) of 2T or 3T length are recorded in the '18T' recording section. 3Tm), the digital sum component DSV becomes '+2', which is more advantageous for the tracking servo operation.

In the last part of the same level section, it is preferable to record a space or mark having a relatively longest pit length among spaces or marks having a pit length satisfying the condition.

For example, in a high-level '36T' recording section corresponding to 'Data 0', 10 spaces of 3Ts or marks 3Tm are 10, and 2Ts or marks 2Tm are 2Ts long. Can be recorded, in a first embodiment, 2Ts, 3Tm, 3Ts, 3Tm, 3Ts, 3Tm, 2Ts, 3Tm, 3Ts, 3Tm, 3Ts, 3Tm, 2Ts, or the second. By way of example, when recorded in the order of 3Ts, 3Tm, 2Ts, 3Tm, 3Ts, 3Tm, 2Ts, 3Tm, 3Ts, 3Tm, 2Ts, 3Tm, 3Ts, both the first and second embodiments are digital sum components (DSV). Becomes 0, but the spaces and marks are recorded in the order of the second embodiment having a relatively long pit length, i.e., 3T space (3Ts) at the end, so that the push-pull signal is detected more accurately at the level transition point. To be possible.

For reference, in the '36T' recording section, when 6 spaces (3Ts) or marks (3Tm) of 3T length and 6 spaces (2Ts) or marks (2Tm) of 2T length are recorded, 2Ts and 2Tm are recorded. It is preferable to record in the order of spaces and marks of 2Ts, 3Tm, 3Ts, 3Tm, 2Ts, 2Tm, 2Ts, 3Tm, 3Ts, 3Tm, 2Ts, 2Tm, 2Ts, or marks and spaces.

Further, in the '18T' recording section, when 4 spaces 3Ts or marks 3Tm and 3 spaces 2Ts or 3Tm 2T are recorded, 2Ts, 3Tm, It is preferable to record in the order of space and mark of 3Ts, 2Tm, 3Ts, 3Tm, 2Ts, or mark and space.

As mentioned above, the above-mentioned preferred embodiment of the present invention has been published for the purpose of illustration, and in particular, the push-pull tracking servo and the DPD tracking servo are well known and well-known techniques. It is easy enough to refer to an example. In addition, within the spirit and scope of the present invention disclosed in the appended claims, various other embodiments may be improved, changed, replaced or added.

The high-density reproduction-only optical disc and the optical disc apparatus and method according to the present invention constructed and constructed as described above have data associated with HFM grooves recorded and stored in the lead-in area of the high-density reproduction-only optical disc such as BD-ROM. By recording in a pre-pit column of shape, the same information as the disc information recorded in the HFM groove method can be recorded, but the same one is used for the entire area of the same high-density reproduction-only optical disc or a high-density rewritable optical disc. By allowing the tracking servo operation to be performed continuously, it is possible to effectively prevent the complicated algorithms for controlling the plurality of tracking servos and the increase in size of the device, and to operate the PLL circuit using the pre-pit from the lead-in area. Can be used to quickly regenerate the reference clock Very useful inventions that are able to be cleaned.

Claims (7)

In a high-density reproduction-only optical disc comprising a lead-in area, a data area and a lead-out area, In a specific area of the lead-in area, a pit column having a recording pattern of a high-frequency modulated bi-phase groove (Bi-phase modulated HFM groove) is recorded and formed. And an odd number (2n + 1) number of spaces and marks or a sum of marks and spaces are repeatedly recorded in the same level section of the high-frequency modulated bi-phase groove. The method of claim 1, And the specific area is a recording area corresponding to a permanent information & control data (PIC) area in which main general information of the disc is permanently recorded and stored among the lead-in areas of the high density rewritable optical disc. The method of claim 2, The high-density reproducing optical disc is 'Blu-ray Disc-ROM', and the high-density rewritable optical disc is 'Blu-ray Disc Rewritable'. The method of claim 1, Spaces and marks are recorded to the left and right at the low level transition point of the high frequency modulated bi-phase groove, and marks and spaces are recorded to the left and right at the high level transition point. High-density reproduction-only optical disc. The method of claim 1, And at least one of the space and the mark or at least one of the mark and the space is recorded with a minimum pit length. The method of claim 1, The space and mark, or mark and space, is any pit whose digital sum value (DSV) has zero or minimum value within the same level interval of the high frequency modulated bi-phase groove. An optical disc for high density reproduction, characterized by being recorded in lengths. The method of claim 6, Spaces and marks, or marks and spaces, repeatedly recorded in the same level interval of the high frequency modulated bi-phase groove, are recorded at arbitrary pit lengths where the digital sum component (DSV) has zero or minimum value. But At the last part of the same level section, a space or mark having a relatively longest pit length among the pit length spaces or marks satisfying the above conditions is recorded and formed.