JPH07153077A - Optical data-recording apparatus - Google Patents

Abstract

PURPOSE:To obtain a high-speed and high-density optical data-recording apparatus which reproduces and records data to a data-recording medium by laser spots, by recording and reproducing modulated data per 2 pits to a conventional 1-pit recording area of a recording track. CONSTITUTION:When recording is carried out, data are received from a host device 1 via an interface 2, and after an error correction code is added and interleaved at 3, the data are modulated at 4 for the purpose of recording. Thereafter, an array of pit data per 2 pits is generated by a code-word converter 8 from consecutive 1-pit data. Then, an optional recording laser is controlled by a laser controller 10, so that an optical head 5 emits laser spots by the laser power of the optional recording laser. Pit data are consequently recorded to a data-recording medium 6.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical information recording device, and more particularly to an optical information recording device for reproducing and recording data by an optical head having one laser and two recording-only lasers.

[0002]

2. Description of the Related Art Conventionally, an optical information recording apparatus includes a read-only type apparatus, a write-once type apparatus capable of writing and reproducing once, a magneto-optical recording method and a phase change recording method capable of reproducing and rewriting. There are rewritable devices.

Recording methods in these optical information recording apparatuses include a pit position recording method in which the center portion of the pit is used as data and a pit edge recording method in which the edge portion of the pit is used as data.

First, a conventional pit position recording type optical information recording apparatus will be described with reference to the drawings.

FIG. 3 is a block diagram for explaining processing at the time of reproduction and recording of the conventional optical information recording apparatus, FIG.
FIG. 3A is a diagram for explaining processing during reproduction, and FIG. 3B.
FIG. 6 is a diagram for explaining a process at the time of recording.

At the time of reproduction, as shown in FIG. 3A, the optical head 1 which reproduces and records data by one laser.
In step 5, a laser spot is emitted by an arbitrary reproducing laser power to reproduce data from the information recording medium 16, data demodulation 17 is performed, interleaving is canceled, and error correction 13
To restore the original data. This data is transmitted to the host device 1 via the interface 12.

At the time of recording, as shown in FIG. 3B, after receiving data from the host device 11, the interface 12
After the error correction code is added by the error correction 13 via the interleave and interleaved, the data modulation 14 for recording is performed, and the optical head 15 for reproducing and recording by one laser is used.
Then, a laser spot is emitted by an arbitrary recording laser power to record the modulated data on the information recording medium 16.

Next, a conventional optical information recording apparatus of the pit edge recording system will be described with reference to the drawings.

FIG. 4 is a diagram for explaining a conventional pit edge recording system, and FIG. 4 (a) is a diagram showing codewords.
FIG. 4B is a diagram showing a recorded pit array, and FIG. 4C.
FIG. 6 is a diagram showing a reproduced detection signal.

During reproduction, as shown by the pit arrangement in FIG. 4B, the laser spot is adjusted to an arbitrary read power by the laser A, and then the laser spot 1 is emitted along the recording track of the information recording medium. The recorded pit data signal is detected. As shown in the detection signal of FIG. 4C, when a change in the reproduced analog waveform is monitored, a level change occurs in the electric signal of the detection signal with respect to an arbitrary time axis, and the level is compared with a preset level 1. By doing so, the pit data is determined. When the electric signal of the reproduced waveform has changed and its level has reached level 1, the pit data is "1". When the electric signal of the reproduced waveform has no change, the pit data is "0" regardless of the level 1. "Play as. Then, the data is shown in FIG.
Convert to the code word of (a) to obtain valid pit data.

At the time of recording, the laser A emits a laser spot with respect to the code word shown in FIG. The relationship between the pit data and the laser A is defined as follows in the recording process. When recording the pit data of "1", the laser spot 2 is emitted from the laser 1 with an arbitrary write power. Further, when recording "0" pit data, the same data as the previous pit is recorded so that the detection signal does not change in accordance with the previous pit recording.

In the pit edge recording method, recording is performed at the edges on both sides of the pit, as compared with the pit position recording method in which the center portion of the pit is used as data.
Since a denser pit arrangement is possible, the recording density can be increased, but at present, the capacity can be doubled as compared with the pit position recording method.

[0013]

The pit position recording method of the above-mentioned conventional optical information recording apparatus can increase the recording density as compared with the pit position recording method, but the value is at most about double, The increase in recording capacity was also about double.

[0014]

The optical information recording apparatus of the present invention reproduces data by a laser spot on a track of an information recording medium having a concentric circle or spiral groove and a track using the groove. In an optical information recording apparatus for recording, an optical head having one first laser for reproducing and recording data and two second lasers dedicated for recording and two pieces of data modulated by the optical head are recorded. A recording function for recording each pit in a pit recording area of a track by one first laser and two second lasers, and a predetermined slice of a detection signal of data recorded by the recording function. It is characterized by having a reproduction function of performing reproduction by detecting with one first laser at a level.

[0015]

Embodiments of the present invention will now be described with reference to the drawings.

FIG. 1 is a block diagram for explaining processing at the time of reproduction and recording of an embodiment of an optical information recording apparatus according to the present invention, and FIG. 1A is a diagram for explaining processing at the time of reproduction. FIG. 1B is a diagram for explaining the process at the time of recording.

At the time of reproduction, as shown in FIG. 1A, a laser for reproduction is selected by the laser controller 10, and the optical head 5 is driven by a laser spot with an arbitrary laser power for reproduction.
Thus, the pit data information recorded on the medium is reproduced from the information recording medium 6, and the detection signal obtained at the reproducing laser spot is detected as an electric signal having a reproduced analog waveform. Then, the level converter 9 monitors the rate of change of the electric signal, reproduces the pit data at the position where the preset electric signal level (slice level) is present, and reproduces the data recorded on the information recording medium 6. 00 ",
It is detected as pit data of a 2-pit array of "01", "10", or "11". Furthermore, in order to obtain continuous pit data from the 2-pit data array, the pit data is organized by the codeword converter 8 to create effective pit data. Then, after that, the pit data is demodulated 7 to deinterleave, error correction 3 is performed, and the recorded data is restored. This is transmitted to the host device 1 via the interface 2.

At the time of recording, as shown in FIG. 1B, data is received from the host device 1 through the interface 2, an error correction code is added with an error correction code and interleaved, and then data modulation for recording is performed. Then, the code word converter 8 generates a pit data array in units of 2 pits from the continuous pit data of 1 pit, the laser controller 10 controls an arbitrary recording laser, and the optical head 5 controls an arbitrary recording laser power. Thus, the laser spot is emitted to record the pit data on the information recording medium 6.

Next, an information recording method by the optical information recording apparatus of this embodiment will be described with reference to FIGS.

2A and 2B are views for explaining an information recording system by the optical information recording apparatus of this embodiment, FIG. 2A is a diagram showing a code word, and FIG. 2B is a diagram showing a recorded pit array. 2 (c) is a diagram showing a reproduced detection signal, FIG.
(D) is a figure which shows the level determination reference | standard of a detection signal.

During reproduction, as shown by the pit arrangement in FIG. 2B, after the laser B adjusts the laser spot to an arbitrary reproduction laser power, conventional optical information recording is performed along the recording track of the information recording medium. Similar to the device, the laser spot 1 is emitted to detect the recorded pit data signal. As for the detected signal, as shown by the detection signal of FIG. 2C, the level converter 9 monitors the change of the reproduced analog waveform, and when the level change of the electric signal of the detection signal with respect to an arbitrary time axis occurs. The electrical signal level of
The pit data is judged by comparing with an arbitrary electrical signal level (slice level) set in advance. As shown in FIG. 2 (d), the level judgment is that the pit data is “01” when the electric signal of the reproduced waveform has changed and the electric signal of the reproduced waveform has changed, and the level 1 has not been reached. When the level has reached 1 but has not reached level 2, the pit data is "10", and when the level 2 has been reached due to a change in the electrical signal of the reproduced waveform, the pit data is "1".
1 ", the pit data is reproduced as" 00 "regardless of the level 1 and the level 2 when there is no change in the electric signal of the reproduction waveform. Then, the code word converter 8 makes the data of 2 pits data array 1 continuous. Convert to a pit-processable data array.

At the time of recording, 1 of the codeword in FIG.
The pit data of the pits is converted into a continuous code word of 2 pits by the code word converter 8, and the laser controller 10 emits a laser spot from an arbitrary laser. The relationship between the pit data and the three lasers is defined as follows in the recording process. When recording "01" pit data, laser spot 2 is emitted from laser A with an arbitrary recording laser power, and "10"
When recording the pit data of, the laser spot 2 by the laser A and the laser spot 3 by the laser B emit a laser spot with an arbitrary laser power, and “11”
At the time of recording the pit data, the laser spot 2 with the laser A, the laser spot 3 with the laser B, and the laser spot 4 with the laser C emit a laser spot with an arbitrary laser power to record different pit data. Further, the "00" pit data corresponds to the same data as the previous pit so that the detection signal does not change according to the previous pit recording as in the conventional pit edge recording method.

[0023]

As described above, the optical information recording apparatus according to the present invention records and reproduces data by the optical head having one laser and two lasers dedicated to recording, thereby achieving the conventional pit edge recording. There is an effect that data recording can be performed about twice as much as that of the method and about four times as much as that of the conventional pit position recording method.

Further, the optical information recording apparatus of the present invention can process the data of 2 pits at a time, so that there is an effect that the data recording and reproducing time can be reduced to one half of the conventional recording method.

[Brief description of drawings]

FIG. 1 is a block diagram for explaining processing during reproduction and recording in an embodiment of an optical information recording apparatus according to the present invention. FIG. 1A is a diagram for explaining the processing during reproduction. FIG. 1B is a diagram for explaining the process at the time of recording.

FIG. 2 is a diagram for explaining an information recording method by the optical information recording apparatus of this embodiment. FIG. 2A is a diagram showing a codeword. FIG. 2B shows the recorded pit array. FIG. 2C is a diagram showing the reproduced detection signal. FIG. 2D is a diagram showing the level determination standard of the detection signal.

FIG. 3 is a block diagram for explaining processing at the time of reproduction and recording of the conventional optical information recording device. Figure 3 (a)
[Fig. 8] is a diagram for explaining a process during reproduction. Figure 3 (b)
FIG. 6 is a diagram for explaining a process at the time of recording.

FIG. 4 is a diagram for explaining a conventional pit edge recording method. FIG. 4A is a diagram showing a codeword. FIG. 4B shows the recorded pit array.
FIG. 4C is a diagram showing a reproduced detection signal.

[Explanation of symbols]

 1 Host Device 2 Interface 3 Error Correction 4 Data Modulation 5 Optical Head 6 Information Recording Medium 7 Data Demodulation 8 Codeword Converter 9 Level Converter 10 Laser Controller 11 Host Device 12 Interface 13 Error Correction 14 Data Modulation 15 Optical Head 16 Information Recording Medium 17 Data demodulation

Claims (2)

[Claims] 1. An optical information recording apparatus for reproducing and recording data with a laser spot on the track of an information recording medium having a concentric or spiral groove and a track using the groove, An optical head having one first laser for reproducing and recording and two second lasers dedicated for recording;
A recording function of recording the data modulated by the optical head in units of 2 pits in a 1-pit recording area of the track by the one first laser and the two second lasers, respectively, and the recording function. An optical information recording apparatus having a reproducing function of detecting a detection signal of the data recorded by the above-mentioned one first laser with a predetermined slice level and reproducing the detected signal. 2. A laser controller for controlling the one first laser and the two second lasers according to the content of the data, and a change in the reproduced waveform reproduced by the reproducing function is judged and reproduced. 2. The optical information recording apparatus according to claim 1, further comprising a level converter for converting the converted data into a processable array and a codeword converter for controlling the codeword converted by the level converter.