JPH1083662A - Optical disk - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently use an optical disk having a recording medium which can rerecord information optically. SOLUTION: This disk is provided with first recording regions tO-tE in which plural reproducing information is recorded, and a second recording region TOC in which position information corresponding to each recording start point and recording finish point in the first recording region of plural reproducing information is recorded, when new reproducing information is overwritten on reproducing information already written in the first recording regions tO-tE, by generating a recording start point at the next recording operation based on the recording last point of overwritten new reproducing point and controlling the second recording region TOC, a residual region caused in the case of that length of new reproducing information is shorter than length of the overwritten reproducing information can be specified as a recordable region.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an optical disk capable of erasing and recording.

[0002]

2. Description of the Related Art Normally, when information is recorded on a recording medium, there is a demand to record information uniformly over the entire recording medium so that there is no place where the information is not recorded on the recording medium. In the case of a cassette tape used in a conventional tape recorder or digital audio tape recorder (DAT), when recording is desired to be continued following the previous recording, the cassette may be directly loaded into the tape recorder and recorded. This is because the tape is wound on a reel and the subsequent location is already stored.

[0003]

However, in such a cassette tape, if it is rewound once and reproduced at another place, it is impossible to immediately search for the continuation of the previously recorded portion. .

[0004] An optical disk is conceivable as a recording medium. Optical discs are divided into read-only discs and optical recording discs, and the latter are write-once optical discs (Write-once optical discs), which can be recorded once and permanently, and rewritable optical discs (Erasable optical discs), which can be erased and written. Classified as

By the way, in the case of a rewritable optical disk, that is, an erasable optical disk, it is not stored in the form of a tape in shape, and even if the optical pickup is held at a previous position, the original state may vary depending on various conditions. Not only is it difficult to return to the position of the optical disk, but once the optical disk is replaced or removed, it is impossible to immediately access the continuation of the previously recorded location.

In the case of a disk that cannot be erased or overwritten, such as a write-once optical disk, it is possible to access the head of an unrecorded portion by checking whether or not it has already been recorded. The head to be recorded next is not always the unrecorded part, and it is not always easy to record new information following the previously recorded location.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described circumstances, and provides an optical disk capable of immediately accessing a continuation of a previously recorded area to enable continuous recording.

[0008]

An optical disk according to the present invention is an optical disk capable of optically re-recording information, comprising: a first recording area in which a plurality of pieces of reproduction information are recorded; A second recording area in which positional information corresponding to each recording start point and recording end point in the first recording area is recorded, and a new reproduction is performed on the reproduction information recorded in the first recording area. When the information is overwritten, a recording start point for the next recording operation is generated based on the recording end point of the overwritten new reproduction information, and managed in the second recording area, whereby the overwriting is performed. The remaining area generated when the new reproduction information length is shorter than the specified reproduction information length can be designated as a recordable area.

A first recording area (data area) for recording reproduction information and recording position information of the reproduction information, that is, a TOC (Table of Conte
nts) Second recording area for recording information (TOC area)
And the position information corresponding to the re-recording final recording end point when re-recording is performed in the first recording area is recorded and updated in the second recording area. By this, when recording next, it is possible to read the record updated position information and immediately access the continuation location previously recorded, for example, when the new reproduction information length is shorter than the overwritten reproduction information length. The resulting remaining area can be designated as a recordable area.

[0010]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.
This will be described in detail with reference to FIG.

First, according to the present invention, the TO is located outside the first recording area (data area) for recording the first information which is the original reproduction information (ie, audio data of music) on the optical disk.
A second recording area (T) for recording second information such as C information
The provision of the OC region will be described with reference to FIGS.

The provision of the TOC area outside the data area is for reproduction only, but a compact disk (CD) already exists. The configuration of the TOC of the CD is as shown in FIG.
In FIG. 6, the time at point 01 represents the start time of the first music piece, 01 at point A0 represents that the first music piece number is 1, and 06 at point A1 represents that the last music piece number is 6. , 65 of point A2 indicates that the time of the start point of the lead-out is 65 minutes. In order to improve the accuracy, the same three times are recorded.

Therefore, in the present invention, the configuration of the TOC of an erasable optical disk as shown in FIG. 7 is considered with reference to the TOC of a CD. Points 01, 02, and を represent each song number,
The start position (start time) and end position (end time) of these music numbers are expressed in minutes, seconds, and frames.
In the case of an erasable optical disc, the TOC is rewritten at any time according to the written information (in the case of music information, the song number and time).

Next, the time as position information corresponding to the re-recording final recording end point when re-recording is performed in the data area as the first recording area by the optical pickup in the TOC area as the second recording area. Recording and updating of information will be described with reference to FIGS.

It is assumed that the first to third music pieces are recorded on an optical disk on which nothing is recorded at first as shown in FIG. 3A. Then, the TOC information at this time as shown in FIG. 4 is recorded in the TOC area of the optical disc. In other words, the first tune enters the point where the tune number is 01, and the frame number at that time is n + 3. Then, the start time of the first song is recorded as t ₀ , and the end time is recorded as t ₁ . Also,
For the second song, the song number goes to the point as 02,
The frame number at that time is n + 6. And the second
The start time of the song is recorded as t ₁ and the end time is recorded as t ₂ . The second song has the song number 03 and enters the point, and the frame number at that time is n + 9. Then, the start time of the third song is recorded as t ₂ and the end time is recorded as t ₃ . Finally, the last recording end point at this time is A3
Then, the time corresponding to the frame number n is entered at the point, and the time corresponding to the final recording end point, that is, the end time t ₃ of the third music, is recorded at the start time corresponding to the frame number n. Note that in FIG. 3A, the period from the lead-in to the start of the first tune from the absolute time t _{s to} t ₀ corresponds to the area where the TOC information is to be recorded, and from the end time t ₃ of the third tune to the absolute time of the lead-out. During t _E , it corresponds to an unrecorded area.

Next, FIG. 3B shows a state in which the first and second pieces of music are newly overwritten from the beginning in the state of FIG. 3A. Then, at this time, the TOC information as shown in FIG.
Rewritten with information. That is, the end time of the first piece of music 'is rewritten to the start time of the second piece of music t ₁ from t _1' t ₁ from t ₁ to the end time is respectively rewritten to t ₂ 'than t _2, further final The time corresponding to the recording end point is t
Rewritten from ₃ to t ₂ '. That is, at the time of this overwriting, the time corresponding to the final recording end point is not the end time of the first third music, but the end time of the new second music. Note that the second tune recorded first remains from time t ₂ ′ to t ₂ .

Next, if it is desired to continue recording, if overwriting is performed, the time corresponding to the final recording end point is t _3.
'If there is rewritten to, the next record, so may start than t _3, time t _2' more t ₂ is between ~t ₂ is uneconomical will remain without anything rewritten. Therefore the time corresponding to the final recording end point as described above when the overwrite 'if rewritten, the next recording is t _2' t ₂ than t ₃ since starting at, even during the time t ₂ '~t ₂ Rewriting is performed, and as a result, the recording medium is effectively used.

By the way, so-called A which can search the head of each music
Although there is an MS search method, using this, a new song is recorded up to the second song at the time of overwriting, so even if the head of the third song can be searched, thinking that it is sufficient to record from the third song this time, the time t ₂ still remains. between the '~t ₂ is a problem because may remain. Also, there is an unrecorded head search method,
This is effective for the first recording (in the case as shown in FIG. 3A), but for the second and subsequent recordings, the times t ₂ ′ to t _2
This is a problem because it will remain between the _two . Therefore, it is effective to rewrite the time corresponding to the final recording end time at the time of overwriting as in the present embodiment and store it as TOC information.

FIG. 1 shows a circuit configuration of an apparatus for recording / reproducing a disk according to an embodiment of the present invention. Here, a magneto-optical type is used as an example, and the present invention can be applied to a phase change type as well. Needless to say.

In FIG. 1, reference numeral 1 denotes an input terminal to which an analog audio signal is supplied. The audio signal from the input terminal 1 is A / D-converted by an A / D conversion circuit 2 and sent to a signal processing circuit 3. Supplied. When a digital signal is directly supplied to the signal processing circuit 3, the digital signal is applied from the input terminal 4. After performing predetermined signal processing in the signal processing circuit 3, the output signal is supplied to the encoder 5, where it is encoded and supplied to the magnetic field generating means 6. Therefore,
The magnetic field from the magnetic field generating means 6 is modulated by an output signal from the encoder 5 and applied to the magnetic thin film of the optical disk 7. This magnetic field is weak enough that the magnetization is not reversed in the recording direction.

In this state, light is radiated from the optical pickup 8 to the magnetic thin film of the optical disk 7 to locally raise the temperature.
The magnetization of the local region is reversed in the direction of the magnetic field. The magnetic field required for recording corresponds to the coercive force of the magnetic thin film at that temperature, but this coercive force generally decreases as the temperature rises. Therefore, even when the coercive force is large at room temperature, only the portion where the temperature rises is coercive. The magnetic force is reduced and recording is possible even with a weak external magnetic field.

Reproduction uses the fact that light is an electromagnetic wave, and when its polarization plane is reflected by a magnetic thin film, it rotates in opposite directions depending on the direction of magnetization (Kerr effect). This is done by converting this into light intensity with the analyzer being tested.

The signal reproduced by the optical pickup 8 is RF
The signal is supplied to a decoder 10 via an amplifier 9 and is decoded here. An output signal from the decoder 10 is supplied to a signal processing circuit 11, where necessary signal processing such as error detection and correction is performed, and further D / A conversion is performed by a D / A conversion circuit 12, and a desired audio signal is output to an output terminal 13. It is extracted as a signal. When it is desired to directly extract a digital signal without performing D / A conversion, the digital signal is output to the output terminal 14.

Reference numeral 15 denotes a microcomputer, and reference numeral 16 denotes a servo circuit. The servo circuit 16 applies focus servo and tracking servo to the optical pickup 8. A laser drive circuit 17 controls the output level of the laser diode included in the optical pickup 8 by the laser drive circuit 17, and the output level is high during recording and low during reproduction. Reference numeral 18 denotes an operation unit, and 19 denotes a display.

Next, the operation at the time of overwriting will be described with reference to FIG. In step (a), the program is started. In step (b), the microcomputer 15 reads time information corresponding to the final recording end point from the TOC information stored in the built-in RAM in advance, and in step (c), the optical pickup. 8 is accessed to the last recording end point on the optical disk 7.

From this final recording end point, recording of a new song is started in step (d). The microcomputer 15 determines whether or not the recording has been completed in step (e). If the recording has not been completed, the microcomputer 15 waits until the recording is completed. When the recording has been completed, in step (f), the start and end times of each song and the final recording end point are set. The time code such as the corresponding time is taken into the RAM of the microcomputer 15.

Next, in step (g), the optical pickup 8 is moved in the innermost circumferential direction of the optical disk 7 under the control of the microcomputer 15 to access the TOC area. In step (h), based on the time code stored in the RAM of the microcomputer 15, the music information in the TOC area, that is, the TOC such as the start time and end time of each music, etc.
The information is rewritten by the amount changed by overwriting.
Then, the time corresponding to the final recording end point at the time of overwriting is rewritten in step (i), and the program is ended in step (nu).

As described above, in this embodiment, the time as the position information corresponding to the final recording end point is rewritten every time the overwriting is completed. Therefore, when the next recording is performed, the last final recording is immediately performed. The end point can be accessed.

[0029]

As described above, if the optical disk of the present invention is used, the next recording start point based on the recording end point when re-recording is performed on the first recording area which is the data area by the optical pickup is set to the first recording area. 2 is managed in the TOC area, which is the recording area of No. 2, the remaining area generated when the new reproduction information length is shorter than the overwritten reproduction information length can be designated as a recordable area, and the recording medium can be effectively used. Available.

[Brief description of the drawings]

FIG. 1 is a circuit diagram showing an embodiment of the present invention.

FIG. 2 is a flowchart for explaining the operation of FIG. 1;

FIG. 3 is a diagram for explaining the present invention.

FIG. 4 is a diagram for explaining the present invention.

FIG. 5 is a diagram for explaining the present invention.

FIG. 6 is a diagram for explaining the present invention.

FIG. 7 is a diagram for explaining the present invention.

[Explanation of symbols]

6 magnetic field generating means, 7 optical disk, 8 optical pickup, 15 microcomputer, 16 servo circuit,
17 ... Laser drive circuit

Claims (1)

[Claims] 1. An optical disc on which information can be optically re-recorded, wherein: a first recording area in which a plurality of pieces of reproduction information are recorded; and recording start of each of the plurality of pieces of reproduction information in the first recording area. A second recording area in which position information corresponding to a point and a recording end point is recorded, and when new reproduction information is overwritten on reproduction information already recorded in the first recording area, the second recording area is overwritten. Based on the recording end point of the new reproduction information, a recording start point for the next recording operation is generated and managed in the second recording area. An optical disc, characterized in that a remaining area generated when the length is short can be designated as a recordable area.