JPS6185638A - Optical disc recording and reproducing method - Google Patents

Abstract

PURPOSE:To record and reproduce data accurately and stably by detecting and holding the tracking error of a sector mark and performing recording and reproducing on a basis of this held error till detection of the next mark. CONSTITUTION:A sector mark SM is discriminated from the reflected light from a recording surface 10a by a circuit 18 to turn on a switch 22, and meanwhile, a circuit 20 detects the tracking error of the mark SM from the same reflected light, and a signal TER indicating this error is held in a circuit 24 through the switch 22. The tracking error of the mark SM is stored in the circuit 24 even after the mark SM passes a head 16 in accordance with rotation of a disc 10 and the switch 22 is turned off, and a tracking servo actuator 14 performs the control to hold the head 16 in a correct tracking position on a basis of the stored signal TER.

Description

DETAILED DESCRIPTION OF THE INVENTION (Benefits of the Invention) The present invention relates to a method for recording and reproducing data using sector marks recorded in advance on an optical disc without a V-groove.

(Technical Background of the Invention and Prior Art) When recording information on an optical disc without a guide 1115, there is a track on which the information is recorded as a data string. Since the data is formed on the optical disk by an optical head under external control, the radial position of the trunk where data is stored tends to be unstable, and it may not be possible to form ideal tracks. Also record data like this? ≠If the i cat is seven stable, will it be tracked when playing data? This creates a problem where it is difficult for the optical head to follow, leading to increased tracking errors and unstable playback.

('I+] Purpose of the present invention) - The K invention was made in view of the IS situation, and it is an optical disc that controls the position of recording data on an optical disk without a guide groove with high precision, and achieves stable data recording. It is an object of the present invention to provide a disc recording and reproducing method that allows stable reproduction of data.

(Structure of the Invention) The object of the present invention is to provide sector marks in advance with high precision of 1σ at a certain angle H9 or at certain intervals on a concentric or spiral virtual track on an optical disc without a guide groove. Is the sector mark your reference and the data behind it? This is accomplished by recording concentrically or spirally.

That is, the recording and reproducing method of the present invention detects and holds a tracking error 2 of sector marks recorded concentrically in advance on an optical disc without a guide groove, and detects and holds this tracking error 2 until the first sector mark is detected. Data while holding tracking servo based on? Configured for recording or playback.

Another sector mark? In the case of spiral recording, data is recorded or reproduced while controlling the tracking servo based on the sum of the tracking error of the held sector mark and the tracking correction amount corresponding to the disk rotation angle. .

Furthermore, the recording and reproducing method of the present invention performs hold control on the tracking servo during reproduction, and detects data tracking errors in real time and controls the tracking servo in real time from the hold control at least in the data reproduction section. The system is configured to switch to closed-loop control.

(Embodiment) The present invention will be described in detail below based on the embodiment shown in the drawings.

Figure 1 is the fruit of this invention! Xr! Figure 2 is an illustration of fil+creation of purchasing factors for deaf people. In FIG. 1, reference numeral IO denotes an optical disk without a guide groove, and 12 denotes a motor that rotates this optical disk for 10 minutes. Optical disk IO, for example, is made of a bright substrate with metal vapor-deposited on the side surface.

This layer 77f serves as the recording surface 10a. 14 is a tracking surfactuator, and 16 is a recording/reproducing head. The head 16 is moved in the radial direction of the disk IO by the actuator 14. This head 1
6 is a laser and a light splitter.

An objective lens, etc. is provided, and the laser beam is always directed to the recording surface 1.
1.5-2 on 0a. It is controlled by a focus servo (not shown) so as to narrow down and converge to the diameter of Ottm NIQ'. The laser beam is controlled on and off by a control circuit when recording data, and when it hits the recording surface 10a, it deforms that portion by melting and evaporation, thereby forming pits. Further, the head 16 irradiates the recording surface 10a with a laser beam weaker than that during recording during reproduction, and reads out the recorded signal by photoelectrically converting the intensity of the reflected light and electrically processing it.

In this actual fifl, several tens of sector marks SM are recorded in advance with high accuracy on virtual concentric tracks spaced apart by about 2 μm on each track at equal intervals on the disk IO. This sector mark.

It is recorded in the form of a few bits arranged so that it can be distinguished from the data (DATA) recorded after it.

In No. 1, 18 is a sector mark detection circuit which identifies the sector mark SMk from the light reflected by the recording surface 10a, and when it detects the sector mark SM, it outputs an amount of SM signal. The sector marks may be arranged at the same angle with respect to the center of the disk between adjacent tracks, or may be arranged at different angles. 20 is a tracking error detection circuit.

Detects the offset position of the laser beam focused on the recording surface from the track and outputs the TER signal. Methods for detecting this tracking error 2 include the well-known three-beam method, push-pull method, and DPD (differential phase detection method).
se Detection) method is used. 2
2 is SM j? , 24 is a hold circuit that temporarily stores the T ER signal, and 26 is a tracking servo driver.

When recording data using this method, the recording surface 10
The sector mark SM is determined by circuit ]8 from the light reflected by a, and the switch 22 is turned on.

On the other hand, the circuit 20 detects a tracking error of the sector mark SM from the same reflected light. The TER signal indicating this tracking error passes through the switch 22 and is further held in the hold circuit 24.

The disk 10 rotates and the sector mark SM marks head 1.
Even if switch 22 is turned off after No. 6.

The tracking error of the sector mark SM is stored in this hold circuit 24, and the tracking servo actuator 14 moves the head 16f to the correct tracking position, that is, the position where the tracking error of the sector mark SM is zero, based on the stored TER signal. Hold control is applied.

In this way, while the tracking servo is held under control, the data to be recorded in that sector is recorded on the recording surface 10.
written to a. When the next sector mark SM is detected, the circuit 18 turns on the switch 22 again and stores the tracking error of this new sector mark SM in the hold circuit 24 again. Data is sequentially recorded while repeating the above operations.

When reproducing data, the tracking servo is held and controlled until the next sector mark SM is detected, including the data reproducing section, as in the case of recording. A in FIG. 2 shows the amount of operation of the tracking servo actuator 14 during recording and reproduction in this embodiment.

That is, the horizontal axis direction in the figure corresponds to time and corresponds to the position on the track being scanned. Also, vertical @I is head 16
corresponds to the amount of radial movement of the disk.

FIG. 3 is a configuration diagram showing a second actual IM aspect of the present invention. In this actual IM deaf person, the tracking servo is held under control in the same manner as in FIG. 1 at the Q time.

Closed loop control 3 is performed during the data reproduction section during reproduction. That is, during reproduction, the tracking error of the sector mark SM is first stored in the hold circuit 24 by turning on the SM signal.

Further, the data discrimination circuit 28 discriminates whether data information is included in the reflected light from the recording surface 10a.

30 is a mode changeover switch, and when the data discrimination circuit 28 discriminates that the laser beam has entered the data reproduction section, the a contact is turned on and the TER signal, which is the output of the tracking error detection circuit 20, is guided to the subsequent stage. , at other times, a TER signal indicating a tracking error of the sector master SM stored in the hold circuit 24 is guided to the subsequent stage. Any TE that passed through this switch 30
The low frequency component of the R signal is separated by a low pass filter 32, and the high frequency component is separated by a bypass filter 34, and each component is separated by a driver 26a,
26 b'i to drive the tracking servo actuator 14 and another tracking servo actuator 16a built in the head 16. B in Figure 2
indicates the total movement of the actuator 14.16a during this regeneration.

According to this embodiment, the tracking servo system is controlled in a closed loop by the TER signal detected in real time within the data reproduction section.

Even if vibrations are applied during reproduction of this section, accurate tracking is always possible, and data reading errors are less likely to occur. Further, since the trunking actuator 14 and the actuator 16a in the head 16 share the low frequency component and the non-high frequency component of the tracking correction, the responsiveness of the tracking servo is improved.

Is Figure 4 the third implementation book of the present invention? FIG.

In this real/arM, when playing.

The tracking servo actuator 14 is driven by the tracking error of the sector mark SM stored in the hold circuit 24, and the tracking error detected in 1 is determined by the HIk stopper 36, and the actuator 16a in the head 16 is driven via the driver 26C. The fI+3 work at the time of recording is the same as the implementation of Figures 1 and 3[2I, and in the 4th river, the same parts as in Figures 1 and 3 are given the same symbols, so the explanation will not be repeated. do not have.

According to this embodiment, there are the same number of juvenile hairs as in the second embodiment.

51'! ! lIhamoto')'6 Akira OD m 4 Nomi bTh rA Jl'l'j NotX'+ bZ 4
””C eye. In this case, the sector mark SM is recorded in advance on the disk 10 with high accuracy along a virtual spiral line [. Therefore, the rotation fi of the motor 12 (or disk 10) is added to the tracking servo system.
Pulse signal θ indicating J? Counter to count b0: 38,
A D/A converter 40 converts the output of the counter 38 into analog, and a tracking correction amount (one rotation of the disk moves in the half-7f direction by the track interval) determined by the D/A converter 40. ) and the output of the switch 30, an adder 42 is added. The other configurations are 1) the same as those in Section II, FIG. 3;

This fruit! AQ,! In 4 II, when recording 9 data, the tracking error of the sector mark SM is held in the hold circuit 24, and when the sector mark SM is detected, after setting the counter 3se-6, the recording of the disc starting from this sector mark SM is performed. The rotation angle is accumulated on the counter 38.

Therefore, during data recording, the actuator 14 is driven by the sum of the held TERf3 and the tracking M correction due to disk rotation.

In the same method, even during reproduction, the head 16 can correctly follow the spiral track by making corrections as the disk rotates. Note that you can use only 21 actuators (14) or two (14 and 16a).

Of course, it is possible to divide the data into two types (see Figures 3 and 4) as appropriate. Further, within the data reproduction section, the tracking servo system may be controlled in a closed loop using the TER signal detected in real time, and corrections may be made in accordance with the disk rotation.

In each of the following implementations (j!: Fan), recording is performed by forming bits in the recording section 10a of the disk 10.

However, in the case of the case 2, the recording section, which is uniformly magnetized in one direction, is heated to a Curie shell with a laser beam while applying a magnetic field in the 1) direction, and the beam 1 is heated to a Curie shell. The so-called )'e Ia is recorded by magnetizing in the 11η direction.
This invention can also be applied to records recorded in the X-region, and the present invention encompasses such records.

(j,・l light paste IJIV!-) tgu departure 111J is 7E in advance in concentric circles as shown in 1:
1iI7', iself? f, sa: tt The sector mark is planned, the tracking error is memorized, and the tracking servo is held by this memorized tracking error until the 9th sector mark is issued. do. Also, if the sector mark is recorded in a spiral shape, do you record it while adding the tranogin theory j7 city depending on the angle of the disc's rotation? to do. Therefore, on a disk without +l'i'i in 6, the track behind the sector mark is in the position;
In addition, it is possible to stably record data or generate IIf data.

Further, in the present invention, when sector marks are recorded concentrically, recording and reproduction can be performed while holding the tracking servo, so recording and reproduction can be stably performed with a relatively simple configuration. In particular, if closed-loop control is performed in real time within the data reproduction section during reproduction, the reproduction accuracy will be further improved and the operation will be more stable.

[Brief explanation of drawings]

, ITI diagram is (1'q diagram, 2nd diagram) of one embodiment of the present invention.
The figure is an explanatory diagram of the operation, and Figures 3, 4, and 5 are configuration diagrams showing the Sennomino IMQζ of the present invention. 10... Optical disk, 14.16a... Actuator, 18... Sector mark detection circuit. 20...Tracking error detection circuit, 22...
・Switch, 24...Hold circuit. 26.26a, 26b, 26cm--driver. Patent Applicant Fuji Photo Film Co., Ltd. Agent Patent Attorney Yama 1) Text: Katr' 6. 'j:,
i'Yu', +1:, ': (Se1゛Q) Akiso II
+l '1-IIl 10 If1゛I ・Pa1 1j
ノ"l'i' , +"-: l'l□
, I/71 Ill'IV), IJ, Dosho [IJ 5 il 'I-1.゛ [Call 1i 7iS
20 et al. 21) 2 No. 2 Kuraki G) 8 works・shiai stani self s /111t; r, ':'
IIn +l+, -1 ・')/11+ f! l
19 bolts with 1. '[Jawman 11 Tokigamikai'
! +! +++ Foot exposed city center i/l 2 I O+1111
! it R: (,'+20) 77 Shisha! ',
'7 ILM II A Complete 1.1: Representatives and people
Nishi Minoru・1 agent residence address: 〒l f15! , 1! 1-chome, Nishikaiku, Minato-ku, Ichibe [
No. 16 No. 21 self-determination ・S, i+Ii il:c), ゛. (1) Specification page 5, No. 1: li+Il'l, 5-2.117/Ill F'+', Iq
),! =A i + ni)/a: ” l , (1
-1) znom r'j19- l=capture. (2) No. 3 of the drawing [/l ili ir', t /1. .

Claims (1)

[Claims] 2.Claims (1) Tracking errors of sector marks pre-recorded concentrically on an optical disc without guide grooves are detected and held until the next sector mark is detected. An optical disc recording and reproducing method characterized by recording or reproducing data while holding and controlling a tracking servo based on the held tracking error. (2) At the time of reproduction, the hold control is switched to closed loop control in which a tracking error in data is detected and the tracking servo is controlled in real time at least in a data reproduction section. Optical disc recording and playback method. (3) While detecting and holding the tracking error of the sector mark previously recorded in a spiral shape on the optical disc without a guide groove, the rotation angle of the optical disc is detected and the tracking error is held until the next sector mark is detected. An optical disc recording and reproducing method characterized in that data is recorded or reproduced while controlling a tracking servo based on the sum of a tracking error and a tracking correction amount according to a rotation angle. (4) At the time of reproduction, the hold control is switched to closed loop control in which a tracking error in data is detected and the tracking servo is controlled in real time at least in a data reproduction section. Optical disc recording and playback method.