JPH0746427B2 - Optical disk device - Google Patents

Description

The present invention relates to a recording / reproducing apparatus for an optical disc or the like.

[Conventional technology]

Conventionally, when recording on an optical disc such as a write-once type CD that is compatible with a read-only compact disc (hereinafter referred to as a CD), the TOC (table of contents) will be recorded later on the inner circumference of the optical disc.
A blank area is provided for recording the data, and a music signal or the like is recorded from the outside to the outer circumference. Then, when recording is performed up to a predetermined outer peripheral position, or when it is determined that no further recording is performed on the optical disc, the optical pickup is moved to the TOC area on the inner periphery of the optical disc, and the music recorded so far is recorded. Record the table of contents information in this TOC area, and write-once type C
D was the recording completed disc.

Therefore, the EFM (eight to forteen Modulatio) is displayed in the TOC area until the TOC area records the table of contents information.
Since the recording pit by n) is not formed, the HF signal cannot be detected from the optical pickup, but when multiple songs are already recorded in the program area outside the TOC area, the EFM pit example is on the disc. It becomes possible to detect the HF signal. Therefore, it is possible to extract the time code (subcode) information from the HF signal and search for the next recording point, as in the case of reproducing the reproduction-only CD.

In this way, the EFM pit train was traced and a time code search was performed near the additional write point to move to the additional write point.

[Problems to be Solved by the Invention]

However, it takes time to move the optical pickup by performing the time code search while tracing the EFM pit row to the point to be additionally recorded. This is because the rotation speed of the spindle motor must be in a stable state in order to extract the sub code information (time code) from the EFM pit string of the optical disc.

Therefore, when the optical pickup moves over a long stroke, the number of rotations of the spindle motor per unit time is
Since the CLV (Constant Linear Veloci-ty) control system changes at least twice as much, it takes time to settle. After the number of revolutions of this spindle motor has settled down, the time code is read out and it is judged whether or not it is the destination.

If the difference between the number of tracks and the destination is within the search (1-10 kicks) only for the optical pickup actuator,
Since there is no difference in the number of rotations of the spindle motor, the time code can be read immediately after the search.

As described above, when the optical pickup moves a long stroke distance to search immediately before the additional recording point for preparation for additional recording, the spindle motor rotation speed remains stable until the time code is read. This caused the recording standby state to not be possible immediately.

[Means for Solving the Problems]

The present invention, for additional recording, means for moving the optical pickup in the recording direction of the recordable optical disc until the HF signal is no longer detected for the information already recorded on the optical disc, and the HF signal when the HF signal is no longer detected. Means for moving the optical pickup to the recorded area until the HF signal is detected, and when the HF signal is detected, detection of the sub-code is started and track servo is performed by the sub-code and the area is recorded close to the additional point. It is an optical disk device provided with means for moving an optical pickup to detect a time code of a sub code and hold the track.

[Action]

Therefore, when performing a coarse search to the additional recording point, the spindle motor rotation speed per hour is increased even if the optical pickup moves over a long stroke because the presence or absence of the HF signal is recognized without checking the time code. , It is possible to search the additional recording point in a short time without having time to settle.

〔Example〕

FIG. 1 shows a block diagram of an embodiment of the present invention. In the figure, the optical disk 1 is CLV-controlled by a spindle motor 5 to give a necessary rotation speed.

The recorded information on the optical disc 1 is read by the optical pickup 3 and added to the EFM demodulation circuit 8 via the head amplifier 6 and the HF signal detection circuit 7. The output is applied to the system control unit 13 via the sub-code extraction circuit 11, the music signal is demodulated via the demodulation circuit 10, and is output to the output terminal 9.

Further, a subcode signal from the system control unit 13 is applied to the EFM modulation circuit 20 via the subcode insertion circuit 16, and a recording signal from the recording signal input terminal 19 is A / D.
It is added via the converter 18 and the modulation signal processing circuit 17.

The output of the EFM modulation circuit 20 is added to the laser modulation circuit 21,
The output of the laser modulation circuit 21 is applied to the optical pickup 3. A slide control signal from the system controller 13 is applied to the slide device 4 via the slide drive circuit 12.
The optical pickup position detection output from the position sensor 22 and the optical disc 1 mounting detection output from the optical disc sensor 2 are added to the system control unit 13, respectively.

The operation of the above configuration will be described in detail below.

In FIG. 1, when the power is turned on, the system control unit
The output of the optical disc sensor 2 determines whether or not the optical disc 1 is present. When the optical disc 1 is loaded, the optical pickup 3 is moved to the inner circumference side of the optical disc 1 while controlling the position of the optical pickup 3 according to the detection signal from the position sensor 22 attached to the slide device 4.

Now, the optical disc 1 that has been placed has already recorded N songs,
When recording additionally to the N + 1th song, the TOC area will still have E
Although the FM pit row is not formed, there is an EFM pit row in the program area around the TOC area.

Therefore, first, the system control unit 13 checks the output signal from the HF signal detection circuit 7 in the TOC area. Then, the signal from the optical pickup 3 is processed by the head amplifier 6, the HF signal detection circuit 7 and the EFM demodulation circuit 8, and the subcode signal is extracted by the subcode extraction circuit 11.

Here, in the optical disk based on the CD standard, the TOC area (lead-in) contains the table of contents information of the music. Therefore,
If the optical disk has already been recorded, this TOC information will enter the system control unit 13 from the subcode extraction circuit 11 as a subcode signal.
Recognizes that it is a write-once CD or a read-only CD that has completed recording.

In this way, it is possible to determine whether or not the mounted optical disc 1 is recordable. If the HF signal cannot be detected here, it is checked whether the mounted optical disk 1 has not been recorded at all or has already recorded some songs. Therefore, the system control unit 13 checks the output signal from the HF signal detection circuit 7 in FIG. 1 at a position slightly outside the boundary between the TOC area and the program area, and determines whether recording is possible.

Further, when the HF signal cannot be detected, the optical disc is not recorded at all. If an HF signal is detected, check how far it is recorded. The optical pick-up 3, from here, is set as the initial position at a position slightly outside the boundary between the TOC area and the program area.
Through the head amplifier 6 and the HF signal detection circuit 7, the system control unit 13 is moved in the recorded direction until the HF signal is no longer detected.
Controls and drives the slide drive circuit 12 and the slide device 4.

When the HF signal is no longer detected, the slide movement to the outer circumference is stopped, and this time, once with a single kick, etc.
On the contrary, the optical pickup 3 is returned to the inner circumference of the optical disc 1 until the signal is detected.

From this point, the HF signal detection circuit 7, the EFM demodulation circuit 8, and the subcode extraction 11 are performed, and the last input subcode signal when the HF signal is no longer detected is the last point already recorded. . Therefore, the next recordable point can be confirmed by the subcode signal.

Next, in the case where the loaded optical disk 1 has already recorded up to N tunes, the sequence of moving the optical pickup 3 to this additional recording point and setting the recording standby will be described in detail.

Although not shown, when the system control unit 13 receives the recording standby command 14 from the host device, the system control unit 13 moves the optical pickup 3 to the additional recording point of the optical disc. For that purpose, first, the optical pickup 3 is operated via the slide drive circuit 12 to the initial position set at a position slightly outside the boundary between the TOC area and the program area.

Then, the focus closing operation of the optical pickup 3 and the spindle motor 5 are operated.

From this initial position, slide driving is performed in the recorded direction (for example, the outer circumference) until the HF signal from the optical disc 1 is no longer detected. The sliding operation can be performed in a short time with respect to the position of the optical disc. When the HF signal is no longer detected via the optical pickup 3, head amplifier 6 and HF signal detection circuit 7, the system control unit
13 stops driving the slide to the outer circumference. At the time when this sliding operation is stopped, the overshoot has caused the point to go too far to the outer circumference.

Therefore, this time, on the contrary, it returns to the inner circumference until the HF signal is detected by one kick or the like. And the HF signal detection circuit 7
Absolute time code (elapsed time of the program area) of the subcode signal to be added when the HF signal is detected
Then, a subcode (time code) search is performed at a position corresponding to the inside of a few tracks.

Due to the above process, this subcode search has already been completed for several tracks. Therefore, the tracking actuator of the optical pickup 3 completes the kick, and the recording standby is started. The track servo is performed for this time code, the track is held, and the recording start command 15
Will be waiting for.

The above operation flowchart is shown in FIG. First, in step S1, the optical pickup is moved to the initial position, and in step S2, the focus servo and spindle motor servo are turned on. Then, from step S3 to step S5,
The rough search by sliding to the additional recording point ends.

This means that the optical pickup has moved to the position where recording is attempted. Furthermore, in steps S6 to S7,
Reverse overshoot by slide movement to the inner circumference, HF
Kicking back until a signal is detected.

From step S8, extraction of the subcode obtained from the EFM pit sequence is started, and in steps S9 to S10, the absolute time code (elapsed time of the program area) of the subcode signal to be additionally recorded is used for a few tracks. The subcode (time code) at the position corresponding to the inner circumference is searched. When the search is completed, the standby for additional recording preparation is set.

〔The invention's effect〕

As described above, according to the optical disk device of the present invention, since the movement search of the optical pickup immediately before the additional recording point of the long stroke is performed by detecting the presence or absence of the HF signal, the pickup can be moved at high speed, Since the track is held by the time code of the subcode extremely close to the additional recording point, the number of rotations of the recording track can be controlled, and a state in which additional recording is immediately performed can be obtained.

[Brief description of drawings]

FIG. 1 is a block diagram of an embodiment of the present invention, and FIG. 2 is a flow chart in FIG. 1 …… Optical disc 2 …… Optical disc sensor 3 …… Optical pickup 4 …… Slide device 5 …… Spindle motor 6 …… Head amplifier 7 …… HF signal detection circuit 8 …… EFM demodulation circuit 10 …… Demodulation circuit 11 …… Subcode extraction circuit 12 …… Slide drive circuit 13 …… System control unit 16 …… Subcode insertion circuit 17 …… Signal processing circuit 18 …… A / D converter 20 …… EFM modulation circuit 21 …… Laser modulation circuit 22… ... Position sensor

Claims (1)

[Claims] 1. A means for moving an optical pickup in the recording direction of the optical disc capable of recording the information already recorded on the optical disc for additional recording, and the HF signal is not detected. And the above HF
A means for moving the optical pickup to a recorded area until a signal is detected, the sub-code detection is started when the HF signal is detected, the track servo is performed by the sub-code, and the sub-code is approached. An optical disk device comprising means for moving the optical pickup to a recorded area, detecting a time code of the sub-code, and holding the track.