KR100205381B1 - Device and method of distinction for disk type of optic disk recording apparatus - Google Patents

Abstract

Disclosed are a disc type discriminating apparatus and a method thereof according to an optical disc recording apparatus, wherein the disc is distinguished by detecting a difference in reflectance of a disc at a focus-on time by focusing on the drive, and performing a reproduction process for reproducing a signal from the disc. After detecting the wobble signal, it is possible to distinguish the type of disc by detecting whether it is a recording medium or a playback-only medium.

Description

Disc Type Discrimination Device for Optical Disc Recording Device and Its Method

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disc recording apparatus, and more particularly, to a disc type discriminating apparatus and a method thereof of an optical disc recording apparatus capable of performing an optimal recording and reproducing operation by distinguishing types of recording media.

Generally, in a recordable disc, data of a signal to be recorded in the recording mode is divided into pits.

During recording, when a laser beam having a constant recording power is irradiated onto a disk surface made of a specific material, the state is changed to form pits.

At the time of reproduction, the amount of reflection of the material change region corresponding to the pit length is detected to restore the data.

In general, there are two types of discs that change the state of the material to enable recording, such as pigments, which occupy about 80% of the current market, and metals, which occupy about 20%.

If it is assumed that the sensitivity of the two disks is the same as that of Fig. 1A even at the same power, the time when the pits are formed on each disc under the same power and the same condition is the same as that of Fig. 1B.

This is due to the difference in the material composition of the disc, even if the discs differ in their characteristics or in the same company.

Therefore, in order to form a normal pit on a disk manufactured by two manufacturers, the power of the laser beam must be determined as shown in FIG. 1C.

FIG. 2 is a diagram showing an embodiment according to the prior art, in which a laser controller 11 outputs a laser drive signal signal of a predetermined level in accordance with recording data, and a disk 10 in accordance with the laser drive signal of the laser controller 11. ), The laser diode 12 for irradiating a laser beam, the reflected light amount detector 13 for detecting the amount of reflected light from the disk 10, and the output signal from the reflected light amount detector 13 are received and the disk 10 A sensitivity measuring unit 14 for measuring the sensitivity of the control unit 14 and a system control unit 15 for determining the type of disk by comparing the output data of the sensitivity measuring unit 14 with the ROM data to determine the optimum power of the recording laser beam. It is composed of

The system control unit 15 includes a comparator 16 for comparing the ROM data with the output data of the sensitivity measuring unit 14 and a disc type discriminator 17 for discriminating the type of disc according to the comparison result of the comparator 16. It is composed of

As shown in FIG. 3, the sensitivity measuring unit 14 includes first and second differentiators 18 and 19 which sequentially differentiate the output data of the reflected light amount detecting unit 13, and the first and second differentiators based on the recording data. 1 A detection window starting point detector 20 for detecting a detection window starting point from an output signal of the differentiator 18 and a detection window for receiving an output signal of the detection window starting point detector 20 based on recording data and generating a detection window. A sample / hold time generator 22 for generating a starting point for sampling / holding the output signal of the second differentiator 19 based on the generator 21 and the output signal of the detection window generator 21; A sample / hold unit 23 for sampling / holding the output signal of the first differentiator 18 based on the output signal of the / hold time generator 22, and the output signal of the sample / hold unit 23 Analog-to-digital converter 24 that converts and outputs to system control unit 15 It is configured.

Referring to the operation according to the prior art configured as described above is as follows.

In general, when the power of the laser beam for recording is determined on the recording data and irradiated onto the disk, pits are formed. When the laser beam is irradiated as shown in Fig. 4A, the amount of reflected light from the pit is detected as shown in Fig. 4B.

At this time, due to the difference in recording sensitivity, the formation speed of the pits varies and the amount of reflected light is detected differently.

If the amount of reflected light is detected as shown in Fig. 4C, the recording sensitivity has the highest (A) waveform and the lowest (C) waveform.

Therefore, the recording sensitivity can be determined by obtaining the inclination of the waveforms (A) to (C) shown in Fig. 4C.

That is, when the slope is obtained as shown in FIG. 5A, the voltage level V is obtained when the waveform as shown in FIG. ) Is the slope, and you can determine the type of disc according to this value.

This operation is described in the following embodiments.

First, after the recording mode is set, the laser controller 11 that receives the recording data as shown in FIG. 6B determines the power of the recording laser beam and drives the laser diode 12. The disk 10 to which the recording laser beam is irradiated Pits are formed on the bed.

At this time, the reflected light amount and the detection unit 13 detect the reflected light at the pit and output it to the sensitivity measuring unit 14, and the reflected light amount at that time is the same as the waveform of Fig. 6A.

Accordingly, the sensitivity measuring unit 14 sequentially differentiates the output signal of the reflected light amount detecting unit 13 in the first and second differentiators 18 and 19 to output waveforms as shown in FIGS. 6B and 6C, respectively. .

In this case, the sensitivity measuring unit 14 detects the output signal of the first differentiator 18 based on the input of the recording data by the detection window starting point detector 20, that is, the starting point of the detection window, that is, the first differential waveform as shown in FIG. 6E. When the zero-cross point is detected, the detection window generator 21 receives the recording data and based on the detection window start point of the detection window start point detector 20 as shown in FIG. The cross point is detected.

Subsequently, when the sample / hold timing generator 22 checks the output signal of the second differentiator 19 based on the output signal of the detection window generator 21 and outputs a signal as shown in FIG. 6F, the sample / hold timing 23 is output. Is to sample / hold the output signal of the first differentiator 18 based on the output signal of the sample / hold time generator 22.

Accordingly, the sensitivity measuring unit 14 digitally converts the output signal of the sample / hold group 23 by the analog / digital converter 24 and outputs it to the system control unit 15.

At this time, when the comparator 16 compares the ROM data with the output signal of the sensitivity measuring unit 14, the disc type discriminator 17 receiving the result determines the disc type.

Disc type discriminating apparatus of the optical disc recording apparatus according to the prior art has a problem of detecting a disc type using a difference between the detected levels and detecting the reflection level of the amount of light reflected by the same laser beam in order to distinguish the disc type. have.

SUMMARY OF THE INVENTION The present invention has been made to solve the problems according to the prior art, and an object of the present invention is to distinguish a CD-R and a CD-RW disc by the pulse width of a signal at the time of focus, and to reproduce a disc for playback according to whether or not a wobble is available. And a disk type discriminating apparatus and method therefor of an optical disk recording apparatus capable of distinguishing a recording-only disk.

1a to 1c is a view showing the sensitivity and beam power according to the disc type according to the prior art,

2 is a block diagram showing a disc type discriminating apparatus of the optical disc recording apparatus according to the prior art;

3 is a detailed block diagram of the sensitivity measuring unit in FIG.

4A to 4C are waveform diagrams showing the relationship between the amount of reflected light and sensitivity,

5a to 5b is a waveform diagram showing a concept according to the prior art,

6a to 6g are timing diagrams of the operation in FIG.

7A is a block diagram showing a disk type discriminating apparatus of the optical disk recording apparatus according to the present invention;

FIG. 7B is a signal waveform diagram at focus on of FIG. 7A;

8A is a block diagram showing an apparatus for discriminating a reproducing disk and a recording disk of an optical disk recording apparatus according to the present invention;

FIG. 8B is a signal waveform diagram output from the comparator of FIG. 8A,

9 is a flowchart showing a disk type discrimination method of the optical disk recording apparatus according to the present invention.

* Explanation of symbols for main parts of the drawings

30: RF amplifier 31, 41: comparator

32: control unit 40: wobble generator

41: peak detection unit

The disc type discriminating device and the method therefor of the optical disc recording apparatus according to the present invention are characterized in that a disc is reproduced for reproducing a signal from a disc by discriminating the disc type by detecting a difference in reflectance of the disc at a focus-on time by focusing on the drive. During the process, the wobble signal is detected to detect whether it is a recording medium or a read-only medium.

Hereinafter, with reference to the accompanying drawings, a preferred embodiment of the disk type discrimination apparatus and method according to the optical disk recording apparatus according to the present invention will be described.

Fig. 7A is a block diagram showing the disc type discriminating apparatus of the optical disc recording apparatus according to the present invention.

Referring to FIG. 7A, an apparatus for disc type discrimination of an optical disc recording apparatus according to the present invention includes an RF amplifier 30 for amplifying a signal generated from pick-up during focus search, and a threshold voltage ( A comparator 31 for receiving and comparing Vт) and rf signals, and a control unit 32 for receiving a signal generated by the comparator 31 and outputting a disc discrimination signal.

The operation of the disc type discrimination apparatus of the optical disc recording apparatus according to the present invention configured as described above is as follows.

In order to focus the drive, the signal generated from the pickup at the time of focus search is amplified by the RF amplifier 30.

The RF signal amplified by the RF amplifier 30 is input to the comparator 31.

In addition, a threshold voltage is input to the comparator 31.

The comparator 31 compares the applied RF amplified signal with a threshold voltage.

The pulse generated by the comparator 31 is input to the control unit 32 to measure the width of the pulse.

When the pulse width measured by the control unit 32 is determined to be a total reflection disk compared to the case of a predetermined CD, a high signal is output to the high reflection / low reflection terminal, and a low signal is outputted otherwise.

Therefore, the discs CD-R and CD-RW are discriminated according to the high reflection / low reflection signals output from the control unit 32.

As shown in Fig. 7B, the high reflection / low reflection signal has a pulse width of Ta in the case of a high reflection disk and a pulse width of Tb in the case of low reflection.

Since the pulse width reflects the reflectivity of the disk, it can be used to further distinguish the type of disk.

Fig. 8A is a block diagram showing an apparatus for discriminating a reproducing disk and a recording disk of the optical disk recording apparatus according to the present invention.

Referring to FIG. 8A, the apparatus for discriminating a play-only disc and a recording disc of the optical disc recording apparatus according to the present invention is provided with a wobble generator for generating a wobble signal by receiving a pick-up input / output voltage level. 40 and a peak detector 41 for detecting a peak portion of the wobble signal output from the wobble generator 40, and a threshold voltage VT and a wobble signal output from the peak detector 41 are inputted. It consists of a comparator 42 which receives and compares.

The operation of the disc discrimination apparatus for reproducing and recording discs of the optical disc recording apparatus according to the present invention configured as described above is as follows.

First, a wobble signal is generated according to the pickup voltage level applied to the wobble generator 40.

The wobble signal output through the wobble generator 40 is input to the peak detector 41.

The peak detector 41 detects a peak portion of the input wobble signal and outputs it to the comparator 42.

In addition, a threshold voltage is input to the comparator 42.

The comparator 42 compares the applied wobble signal peak portion with a threshold voltage.

The signal generated by the comparator 42 is input to a controller (not shown).

Therefore, when the wobble is detected among the signals generated by the comparator 42, as shown in Fig. 8B, the wobble becomes a high signal as the recording medium.

In addition, as shown in 8b, if the wobble signal is not detected, the signal is a low signal if it is a medium dedicated to playback.

Fig. 9 is a flowchart showing a disc type discrimination method of the optical disc recording apparatus according to the present invention, in which a laser beam is generated on a disc in accordance with a laser drive signal (S101), and focusing (S102).

After calculating the width time of the pulse at the focus-on time (S103), if the pulse width time (reflection) is small compared with the width time of the CD pulse measured by the control unit 32 (S104), it is CD-RW (S105), The low reflection signal is output (S106).

If the pulse width time (reflection) measured is greater than the width time of the CD pulse measured by the control part 32, it is CD-R (S105) and outputs a high reflection signal (S107).

When disc determination of the CD-R and CD-RW is completed, all servo operations required for the reproducing system are turned on (S109), and then a peak portion of the wobble signal is detected according to the pickup voltage level applied to the wobble generator 40. (S110).

If the peak portion is high (S111), the high reflection signal and the low reflection signal are checked (S112).

If it is the high reflection signal, it is a recording-only CD-R disc (S113).

If it is a low reflection signal, it is a recording-only CD-RW disc (S114).

If the peak portion is low, it is a reproduction-only CD disc (S115).

Therefore, the CD-R and the CD-RW can be distinguished by the pulse width of the signal at the time of focus, and the read-only disc and the record-only disc can be distinguished according to the wobble.

The disk type discriminating apparatus of the optical disk recording apparatus according to the present invention has the effect of distinguishing CD-R and CD-RW by the pulse width of the signal at the time of focus.

In addition, there is an effect of distinguishing between a playback-only disc and a recording-only disc, depending on whether the wobble is present.

Claims (7)

An optical disc recording apparatus, comprising: an RF medium width portion for amplifying a signal generated from a pickup during a focus search; A comparator for receiving and comparing a threshold voltage and an RF signal amplified by the RF amplifier; And a control unit for receiving a signal generated by the comparator and outputting a disc discrimination signal. An optical disc recording apparatus, comprising: a wobble generator for generating a wobble signal by receiving a pick-up input / output voltage level; A peak detector for detecting a peak portion of the wobble signal output from the wobble generator; And a comparator for receiving and comparing a threshold voltage and a wobble signal output from the peak sensing unit. A disc discrimination method of an optical disc recording apparatus, comprising: measuring a width time of a pulse at focus on according to a laser driving signal; Comparing the measured pulse width time with the width time of the already measured CD pulse; Determining that the pulse width time is small according to the comparison result and outputting a low reflection signal as a CD-RW disk; Sensing all wobble signals after turning on all servo operations required for a regeneration system according to the low reflection signals; And determining that the peak portion is low as a CD disc for reclamation. 4. The disk type discrimination method of claim 3, further comprising determining that the CD-R disk is large and outputting a high and low reflection signal if the pulse width time is large according to the comparison result. 4. The disc type discrimination method of claim 3, comprising determining that the CD portion is a recording-only CD disc if the peak portion is high. 6. The disk type discrimination method according to claim 5, further comprising the step of determining that the recording-only CD disk has a large pulse width, the recording-only CD disk. The disk type discrimination method of claim 5, further comprising determining that the recording-only CD disk has a small pulse width as a recording-only CD-RW disk.