JPH02105334A - Optical disk driver - Google Patents

Abstract

PURPOSE:To improve the data recording efficiency and to increase data transfer speed by inspecting the reproduction data after obtaining the time difference of synchronizing signals between the record data and the reproduction data. CONSTITUTION:The record data is recorded on an optical disk via a data modulator 1 and a laser diode 3. For the reproduction data received from the optical disk, a synchronizing signal is detected 11 and supplied to a demodulator 12 as well as to a variable delay circuit 4. While the synchronizing signal of the record data is detected 6 and supplied to the circuit 4. The circuit 4 obtains the time difference between both synchronizing signals and then the time difference between the record and the reproduction. The record data is delayed 4 by an extent equal to said time difference and sent to a pattern matching circuit 10. While the reproduction data is detected 9 and sent to the circuit 10. The circuit 10 compares the reproduction data with the record data to count and decide 13 the errors and performs the record again to a substitute sector at a recording defect.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a drive device for recording and reproducing information on and from an optical disk such as a magneto-optical disk.

[Conventional technology]

For recordable optical discs, the recorded data is reproduced immediately after recording, and this is verified by comparing it with the recorded data, unless there is a recording error or defect that exceeds the extent that correct data reproduction can be compensated for. It is used to record again in the prepared area.

[Problem to be solved by the invention]

Although the optical disk drive device has such verification and defect management functions, there is a delay of at least one rotation of the optical disk between recording and reproduction.

This is because the recorded area can only be reproduced once it has come around to the position of the recorded light beam.

For this reason, there was a limit to the improvement in efficiency during recording.

The present invention has been made to solve such problems, and provides an optical disk drive device that improves recording efficiency by using two light beams to perform playback and verification immediately after recording. The purpose is to provide.

[Means to solve the problem]

The optical disk drive device according to the first aspect of the present invention uses a head having a two-beam light source for recording and reproduction, and performs reproduction and verification immediately after recording without waiting for one rotation of the disk.

and means for determining the time difference between the synchronization signal obtained from the recording signal and the synchronization signal obtained from the optical disk by the reproduction light beam, and means for delaying the recording signal by this time difference and comparing it with the reproduction signal. Equipped with.

Further, the optical disk drive device according to the second aspect of the present invention includes means for detecting the total number of error bits and the maximum number of consecutive errors, and means for determining whether or not to record in a replacement sector based on the detected record.

[Function] In the invention of claim 1, the recording light beam records information on the optical disk. Data recorded by projection light from other light beam sources provided on the same head is reproduced without waiting for one rotation of the optical disk.

Therefore, the verification will be carried out immediately. Also, a synchronization signal is detected from the recording and reproduction signals, and the time difference between them is determined. This corresponds to the time difference between recording and reproduction, so if recorded data is delayed by this time difference, it will be synchronized with the reproduced data, and by comparing the two, it can be immediately determined whether or not recording is appropriate. According to the second aspect of the invention, it is possible to immediately determine whether or not to record to a replacement sector.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below based on drawings showing embodiments thereof.

FIG. 1 is a block diagram showing the main parts of the apparatus of the present invention. Recorded data is converted by a data modulator 1 into a signal form suitable for recording on an optical disk, and is used to drive a laser diode 3, which is a light beam source for recording. Circuit 2. The signal is applied to the variable delay circuit 4 and also to the 5sync signal detector 6. A light beam emitted from a laser diode records the recording data on the optical disk. 7 is a laser diode which is a light beam source for reproduction, and 8 is a photodiode which is a light receiving element for reproduction, which are assembled in the same head as laser diode 3 for recording, and the projection area of the light beam is the same as that for recording. The optical disk is on the upstream side of rotation, and the one for reproduction is on the downstream side.

The optical signal received by the photodiode 8 is amplified by an anode amplifier 8a and input to a detector 9, where the waveform is shaped, and the reproduced recorded data is input to a pattern match circuit 10 and a demodulator 12. On the other hand, the detector 9 output is 5y
The signal is applied to the nc signal detector 11.

5ync signal detector reads 5ync from the optical disc.
Detect the ync signal. This 5sync signal is input to the variable delay circuit 4 and demodulator 12. The demodulator 12 demodulates the signal input from the detector 9 and outputs demodulated data.

The pattern matching circuit 10 combines the efforts of two people and supplies it to the error number counting and determination circuit 13. The circuit engineer 3 verifies the reproduced data following recording, and issues an output indicating whether the number of errors is less than a predetermined value. If it is more than a predetermined value, it is determined that the recording is defective and the recording is performed again in a pre-prepared replacement sector.

FIG. 2 is a block diagram showing the configuration of the variable delay circuit 4. As shown in FIG. Each output pulse of the 5sync signal detectors 6 and 11 is R-S.
Cent terminal s1 reset terminal R of flip-flop 41
, and its cent output Q is given to the enable terminal E of the counter 42. Clock pulses from the clock generator 45 are given to the counter 42 as a counting object and to the shift register 43 as shift pulses. The data modulator output, that is, the modulated signal to be recorded is provided to the shift register 43 as a signal to be shifted.

The shift register 43 is a series register having a capacity capable of shifting the number of bits calculated by dividing the assumed maximum value of the time difference between the recorded modulation signal and the signal recorded and reproduced from the optical disk by the shift pulse period. It is an input parallel output, and the parallel output is given to the selector 44. Selector 44
The output of the counter 42 is input as a selection control signal, and in accordance with this input, one of the parallel outputs of the shift register is selected and input to the pattern matching circuit 10.

Next, the operation of the apparatus of the present invention will be explained based on FIG. Data to be recorded is modulated by a data modulator 1, and a laser diode 3 is driven based on the modulated signal to perform recording on the optical disc. On the other hand, the 5sync signal contained in the modulated signal is detected by the detector 6, and its output is as shown in FIG. 3(a). The 5sync signal read from the optical disc is detected by the photodiode 8 on the downstream side of the rotation of the optical disc with a delay of a certain amount of time.
The pulse signal shown in FIG. 3 (BL) is output from the 5-sync signal detector 11. Then, the set output Q of the R-S flip-flop 41 becomes high level between these two pulses as shown in FIG. 3 (C1). .Therefore, the counter 42
is enabled during this time and counts clock pulses. When the counter 42 becomes disabled, the counter 42 stops counting, but this count value is determined by the time delay 1. It will represent. Therefore, the parallel output shifted by t+/T (where T is the clock period) from the input side of the shift register 43 is sent to the selector 44.
If selected, the recorded data delayed by that amount will be synchronized with the reproduced data. In other words, when the output of the selector 44 is applied to the pattern matching circuit 10, it becomes possible to compare it with the simultaneously inputted reproduction data in real time.

Therefore, the optical disc became CAV (Constat Aug.
ular Vet.

city), if the recording device is located on the outer circumferential side of the track corresponding to the signal in Figure 3 (bl), the output of the 5 sync signal detector 11 will be 5 sync as shown in Figure 3 (d). Time h(j+
>tz) will be delayed. In this case, the count value of the counter 42 becomes a small value corresponding to t2, but the selector 44
selects the parallel output closer to the input side of the shift register 43 to synchronize recorded data and reproduced data.

In other words, correct synchronization and pattern matching between the two can be performed regardless of the recording track of the optical disc.

In addition, in the error number counting and determination circuit 13, if the number of errors is 50 bits and the maximum number of consecutive errors is 30 bits (according to ISO512 byte format) as a result of pattern matching, it is determined to be defective and re-recording is performed in a replacement sector. Let it happen.

〔Effect of the invention〕

Since the present invention is configured as described above, verification after recording can be performed with almost no need to wait for rotation of the optical disk, improving the efficiency of data recording and further increasing the data transfer speed with related equipment. Improvements can be made.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of the essential parts of the apparatus of the present invention, FIG. 2 is a block diagram of the variable delay circuit, and FIG. 3 is a time chart for explaining its operation. 3.7...Laser diode 4...Variable delay circuit 5.8...Photodiode 6,11...5yn
c signal detector 10...pattern match circuit 13.
...Error number counting and determination circuit In the figures, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Claims] 1. A head equipped with a light beam source for recording and a light beam source for reproduction, records data by projecting a light beam, and reproduces and records data by projecting a light beam. In an optical disc drive device configured to verify data, means for determining a time difference between a synchronization signal obtained from a recording signal and a synchronization signal obtained from an optical disc by projection of a reproduction light beam; An optical disc drive apparatus comprising means for comparing a recorded signal and a reproduced signal delayed by a time difference. 2. Means for detecting the total number of error bits and the maximum number of consecutive errors in reproduced recorded data, and whether or not to record data in alternate sectors previously provided on the optical disc based on the total number of error bits and the maximum number of consecutive errors. 2. The optical disc drive device according to claim 1, further comprising means for determining whether or not the optical disc drive apparatus has the following characteristics.