KR20010084663A - Apparatus for controlling of optical record medium - Google Patents

Abstract

PURPOSE: A controlling apparatus of an optical record medium is provided to correctly obtain the number of sectors in one track of the current position by detecting the address of a preceding track simultaneous with the address of the current track. CONSTITUTION: An optical pickup(102) writes and reproduces data to/from an optical disk(101). An RF and servo error producing block(103) produces an RF signal, a Focus Error (FE) signal and a radial push-pull signal from electric signals(A,B,C,D) from the optical pickup(102). An LPP and wobble producing block(104) detects an LPP signal and a wobble signal from the push-pull signal. A wobble PLL block(105) phase-locked loops the detected wobble signal. An address decoder(106) detects address informations in the current and the next tracks using the LPP signal. A micom(107) generates a control signal for record reproduction and track jump based upon the address informations detected in the address decoder(106). A disk controller(108) performs servo control in the optical pickup(102) using the control signal from the micom(107).

Description

Apparatus for controlling of optical record medium

The present invention relates to an optical recording medium system, and more particularly, to an apparatus for controlling an optical recording medium having a land prepit (LPP) area.

Generally rewritable optical recording media such as an optical disc include a rewritable compact disc (CD-RW) and a rewritable digital versatile disc (DVD-RW, DVD-RAM, DVD-R), and the like. There is this.

Here, the difference between the DVD-RAM and the DVD-RW / R is that the DVD-RAM records data in both lands and grooves, whereas the DVD-RW / R records data only in the grooves. That is, the DVD-RW / R pre-pits the land track instead of the header of the DVD-RAM indicating the position information as shown in FIG. 1 to record the position information on the groove track, and does not record the data on the land track. Do not. In this case, the location information on the land is called land-pre-pit (hereinafter referred to as LPP). That is, information on the physical address of the groove track is recorded in the pits in advance in the land. In addition, the position information may be recorded in a wobbling shape along the track boundary. Here, the wobbling is a modulated clock that modulates a constant clock to supply information to the disk, for example, information on the corresponding position, information about the rotation speed of the disk, and the like to the power of the laser diode, thereby controlling the information by changing the light beam of the laser. Is recorded at the boundary of the track.

Therefore, in the case of DVD-RW / R, the LPP signal recorded in advance in the land is detected to detect address information indicating the track position. In other words, the radial push-pull signal has address information for the current track and the next track. For example, assuming that the upper direction is an outer circumferential direction as shown in FIG. 1, the LPP detected by the lower land track L1 of the groove track (eg, G2) where the current light beam is located is included in the current groove track (eg, G2). Address information is recorded, and address information of the next groove track (eg, G3) is recorded in the LPP detected by the upper land track (L2) of the groove track (eg, G2).

By the way, the conventional optical disc detects only the address information of the current track from the lower side information of the LPP.

An object of the present invention is to provide an apparatus for controlling an optical recording medium which detects address information of a current track and address information of a next track from a push-pull signal detected in the LPP region.

1 shows the structure of an optical record carrier having an LPP region;

2 is a block diagram of a control device of the optical recorder according to the present invention;

3 is a detailed block diagram of an LPP and wobble generator and an address decoder of FIG.

(A) to (c) is an operation waveform diagram of each part of the LPP and wobble generator of FIG.

Explanation of symbols for main parts of the drawings

101: optical disk 102: optical pickup

103: RF and servo error generator 104: LPP and wobble generator

105: wobble PLL section 106: address decoder

107: micom 108: disk control unit

An apparatus for controlling an optical recording medium according to the present invention for achieving the above object includes a land and a groove track, one of which records data, and another track has information on the position of the data recording track. An information detecting section for detecting information on the data recording track in an optical recording medium for recording and reproducing a recorded optical recording medium, and positional information for reading position information of a current data recording track and a next data recording track from the detected information; It characterized in that it comprises a decoder.

The information detector detects a wobble signal by band-pass filtering the difference signal of the light reflection signal from the optical recording medium, and the difference signal of the light reflection signal from the optical recording medium to a predetermined upper slice level. And a second slice unit for slicing the difference signal of the light reflection signal from the optical recording medium to a preset lower slice level.

The wobble signal detector is enabled by an inverted signal of the PLL wobble signal, and decodes an output of the first slice unit to read position information of a next data recording track, and to the PLL wobble signal. And a second decoding section for decoding the output of the second slice section to read position information of the current data recording track.

The location information is characterized in that the address information that can know the location of the current track.

Other objects, features and advantages of the present invention will become apparent from the following detailed description of embodiments taken in conjunction with the accompanying drawings.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Fig. 2 is a block diagram showing the configuration of a control apparatus for an optical recording medium according to the present invention, including an optical disk 101 capable of rewriting data, an optical pickup 102 for recording and reproducing information on the optical disk 101, and RF and servo error generation unit 103 for generating an RF signal, a focus error (FE) signal, a radial push-pull signal, and the like from the electrical signals A, B, C, and D output from the optical pickup 102. LPP and wobble generation unit 104 for detecting the LPP signal and the wobble signal from the push-pull signal, a wobble PLL unit 105 for phase-locking the detected wobble signal (PLL), and the PLL wobble signal. An address decoder 106 for simultaneously detecting address information of a current track and a next track using the LPP signal, and a control signal for recording, reproducing, track jumping, etc. according to the address information detected by the address decoder 106. The generated microcomputer 107, and It consists of a disk controller 108 for performing servo control in the optical pickup 102 by a control signal of the microprocessor-based (107).

3 is a detailed block diagram of the LPP and wobble generation unit 104 and the address decoder 106. The LPP and wobble generation unit 104 is an information detection unit and detects a wobble signal by bandpass filtering a push-pull signal. A band pass filter (BPF) 201 to be output to the wobble PLL unit 105, a first slice unit 202 to remove DC from the LPP signal, and then slice at an upper slice level, and the LPP The second slice unit 203 is configured to remove DC from the signal and slice at the lower slice level.

The address decoder 106 is a location information decoder, and is enabled by the inverted output of the PLL wobble signal, wherein a first LPP which decodes an output of the first slice unit 202 to detect an address of a next track. A second LPP decoding unit 302 which is enabled by the decoding unit 301, the output of the PLL wobble signal, and at this time decodes the output of the second slice unit 203 to detect an address of a current track; The microcomputer interface 303 outputs the outputs of the first and second LPP decoding units 301 and 302 to the microcomputer 107. Here, a servo digital servo processor (DSP) may be used instead of the microcomputer 107.

In the present invention configured as described above, the optical disc 101 has a signal track structure of land and grooves, but since the land track is pre-fitted, data can be recorded or reproduced only in the groove track.

At this time, the optical pickup 102 causes the light beam focused on the objective lens to be placed on the signal track of the optical disk 101 under the control of the disk control unit 108, and also condenses the light reflected from the signal recording surface back to the objective lens. It then enters the photodetector for detection of the focus error signal and the push-pull signal. The photo detector includes a plurality of photo detectors, and electrical signals A, B, C, and D in proportion to the amount of light obtained from each photo detector are output to the RF and servo error generator 103.

The RF and servo error generating unit 103 is an RF signal for reproducing data from the electrical signals A, B, C, and D output from the photo detector, a focus error signal FE for servo control, and a push-pull signal. (PP) and the like. At this time, the push-pull signal is output to the LPP and wobble generator 104.

Here, the push-pull signal is a tracking error signal detected by the push-pull method, and the reflected light from the optical disk is divided into two and detected by comparing the respective intensities. That is, when the laser beam is irradiated to the pit, diffraction occurs. In the correct tracking state, the left and right diffraction light is symmetrical about the optical axis. When the reflected light is detected by the two-segment photodetector in the optical pickup 102, the output difference becomes zero. In other words, the push-pull signal becomes zero. However, if the spot deviates to the left with respect to the pit, the diffraction effect of the laser light incident on the left side of the pit decreases, and the diffraction light becomes asymmetrical to detect a push-pull signal in which the reflected light on the left side increases. On the contrary, if the signal deviates to the right side, a push pull signal in which the right side increases is detected. Since the land (LPP) area in which the groove track position information is pre-fitted and recorded is a non-recording area, the reflectance is high. Therefore, the push-pull signal greatly changes up and down to follow it in the LLP region.

That is, the push-pull signal of the LPP region is largely generated up and down with an arbitrary rule in the wobble signal as shown in FIG.

Therefore, after removing the DC of the push-pull signal from the first slice unit 202 of the wobble and LPP generation unit 104, the push-pull signal from which the DC is removed is sliced to a predetermined upper level as shown in FIG. Then, as shown in Fig. 4B, an LPP signal capable of detecting the address of the next track is output.

In addition, when the second slice unit 203 removes the DC of the push-pull signal and slices the push-pull signal with the DC removed to a predetermined lower level as shown in FIG. 4A, FIG. 4C. An LPP signal capable of detecting the address of the current track is output as follows.

Meanwhile, the BPF 201 of the wobble and LPP generation unit 104 detects the wobble signal from the push pull signal by band pass filtering the push pull signal and outputs the wobble signal to the wobble PLL unit 105.

The wobble PLL unit 105 applies a PLL to the detected wobble signal and outputs the PLL to the address decoder 106.

The reason why the PLL is applied to the wobble signal is that a constant wobble signal is always generated by the PLL even if the wobble signal is not properly detected due to a disc defect or the like, so that the address decoder 106 simultaneously decodes the address information of the current track and the next track. To do that.

That is, the first LPP decoding unit 301 of the address decoder 106 is enabled by the inverted output of the PLL wobble signal, and then is pushed by the wobble and LPP generation unit 104 and sliced to an upper slice level. The signal is decoded to detect address information of the next groove track. Also, the second LPP decoding unit 302 decodes the push-pull signal sliced to the lower slice level by the wobble and LPP generation unit 104 after being enabled by the output of the PLL-formed wobble signal. Address information is detected. The current groove track means a groove track to which the current light beam follows.

That is, the first and second LPP decoding units 301 and 302 simultaneously detect the address information of the next groove track and the current groove track by the PLL wobble signal. This assumes that the upper direction is the outer circumferential direction as shown in FIG. 1, the LPP detected by the land track (eg, L1) located on the inner circumference of the groove track (eg, G2) has address information of the current groove track (eg, G2). This is because the address information of the next groove track (e.g. G3) is recorded in the LPP which is recorded and detected by the land track (e.g. L2) located on the outer circumference of the groove track (e.g. G2).

The detected current groove track and address information of the next groove track are output to the microcomputer 107 through the microcomputer interface 303, and the microcomputer 107 receives various information from the address information of the current groove track and the next groove track. Detect. For example, although the number of sectors is different for each track, by using the address information of the current track and the address information of the next track detected by the present invention, it is possible to know how many sectors are included from the current track position to the next track position. Therefore, the microcomputer 107 can use this information to reduce the calculation error in the sector length when calculating the position to track jump to seek. In addition, since a defect and the like of the preceding address can be known in advance, such an error can be interpolated in advance accurately. This speeds up access time. That is, the track jump can be performed quickly while the servo is stabilized by increasing the accuracy of the track jump.

In addition, by accurately determining the number of sectors existing in one track of the current position, the spindle control becomes easy and the data PLL control becomes easy.

On the other hand, the present invention can be applied to all LPP disks.

As described above, according to the control apparatus of the optical recorder according to the present invention, by detecting the address of the preceding track at the same time as the address of the current track, it is possible to accurately determine the number of sectors in one track of the current position, which is a seek or track jump. Can be used as supplementary information. In addition, an error due to a defect of a preceding address can be accurately interpolated in advance. This can reduce the access time.

Those skilled in the art will appreciate that various changes and modifications can be made without departing from the spirit of the present invention.

Therefore, the technical scope of the present invention should not be limited to the contents described in the embodiments, but should be defined by the claims.

Claims (4)

A control apparatus of an optical recording / reproducing apparatus, comprising: a land and groove track, wherein data is recorded in one of the tracks and an optical recording medium in which position information of the data recording track is recorded in another track; An information detector for detecting information about the data recording tracks; And And a position information decoder for reading position information of a current data recording track and a next data recording track from the detected information. The method of claim 1, wherein the information detection unit A wobble signal detector for detecting a wobble signal by band-pass filtering the difference signal of the light reflection signal from the optical record carrier; A first slice unit which slices a difference signal of a light reflection signal from the optical recording medium to a predetermined upper slice level; And a second slice section for slicing a difference signal of the light reflection signal from the optical recording medium to a preset lower slice level. The wobble signal detector of claim 2, wherein the wobble signal detection unit And a wobble PLL for outputting the detected wobble signal to the position information decoder by performing a phase locked loop (PLL). 4. The wobble signal detector of claim 3, A first decoding unit enabled by the inverted signal of the PLL wobble signal, for decoding the output of the first slice unit to read position information of a next data recording track; And a second decoding unit enabled by the PLL wobble signal and configured to decode the output of the second slice unit to read position information of a current data recording track.