KR20050074794A - Apparatus and method for detecting disc using push pull signal - Google Patents

Abstract

The present invention relates to an apparatus and method for recording / reproducing an optical recording medium, and more particularly, to a disc determination apparatus and method using a push-pull signal for determining the type of an optical disc using a push-pull signal. Disk determination method using the push-pull signal generates a push-pull signal from the RF SUM signal when the servo is operated, measures the peak-to-peak voltage of the push-pull signal, and compares the peak-to-peak voltage with the reference voltage. It is characterized by determining whether the disc is a DVD-R disc or a DVD-ROM disc. According to the present invention, by determining that the type of media is DVD-R or DVD-ROM by using the push-pull signal, it is possible to implement proper servo operation and function implementation for the disk and to increase stability.

Description

Apparatus and method for detecting disc using push pull signal}

The present invention relates to an apparatus and method for recording / reproducing an optical recording medium, and more particularly, to a disc determination apparatus and method using a push-pull signal for determining the type of an optical disc using a push-pull signal.

In the case of an optical recording device, it is possible to determine whether it is a DVD-R disc by using wobble information, but in the case of an optical reproducing device, the wobble information cannot be read. Although reading the media information stored in the optical disc indicates that it is a DVD-R, setting the DVD-R again at this time lengthens the lead-in time.

For reference, the wobble signal is a signal that enables disc MSF reading by a wobble of a certain period in the track direction of a recordable disc, and is a sine wave of 22.05 ± 1 KHz at 1x speed. By reading the wobble signal, it is possible to read the time code of the optical disc and data for disc determination.

Therefore, even in an optical reproducing apparatus that cannot read wobble information, it is determined that the DVD-R disc is a servo setting suitable for DVD-R characteristics.

The technical problem to be achieved by the present invention is to determine the type of optical disc is a DVD-R or DVD-ROM by using a push-pull signal to enable proper servo operation setting and function implementation for the disc and to improve stability. An apparatus and method for determining a disk using a push-pull signal are provided.

Disc determination device using a push-pull signal for solving the technical problem to be achieved by the present invention is a pickup unit for detecting the amount of beam reflected from the optical disk; An RF signal processor configured to generate an RF SUM signal based on the detected beam amount; It is determined by generating a push-pull signal from the RF SUM signal and measuring peak-to-peak voltage and comparing the peak-to-peak voltage with a reference voltage to determine whether the optical disk is a DVD-R disk or a DVD-ROM disk. It is preferable to include a system control unit for outputting a servo operation control signal corresponding to the disk.

In the present invention, when the peak-to-peak voltage is greater than the reference voltage, the system controller determines that the optical disk is a DVD-R disk having a deeper pit depth.

In the present invention, when the peak-to-peak voltage is less than the reference voltage, the system controller determines that the optical disk is a DVD-ROM disk having a shallower pit depth.

Disc determination method using a push-pull signal for solving the technical problem to be achieved by the present invention (a) generates a push-pull signal from the RF SUM signal when the servo is operated and the peak-to-peak voltage of the push-pull signal Measuring; And (b) comparing the peak-to-peak voltage with a reference voltage to determine whether the optical disk is a DVD-R disk or a DVD-ROM disk.

In the present invention, in the step (b), when the peak-to-peak voltage is greater than the reference voltage, the optical disk is determined to be a DVD-R disk having a deeper pit depth.

In the present invention, in the step (b), when the peak-to-peak voltage is lower than the reference voltage, the optical disk is determined to be a DVD-ROM disk having a shallower pit depth.

Hereinafter, with reference to the accompanying drawings will be described in detail the present invention.

1 is a block diagram showing the configuration of a disc determination device using a push-pull signal according to the present invention, which includes an optical disc 100, a pickup unit 110, an RF signal and a servo error signal processing unit 120, and a servo unit 130. ), And the system control unit 140. In the present invention, the pickup unit 110 includes an objective lens 111, a beam splitter 112, a laser diode (LD) 13, a photo detector 114, and a focusing actuator 115.

2 is a flowchart illustrating an operation of a disc determination method using a push pull signal according to an embodiment of the present invention, in which the servo operation is turned on (200). Measuring the peak voltage (210), determining whether the peak-to-peak voltage is greater than the reference value (220), and determining the DVD-R disc if the peak-to-peak voltage is greater than the reference V voltage ( 230, if the peak-to-peak voltage is lower than the reference voltage, determining 240 as a DVD-ROM disk, and setting an appropriate servo operation signal for the disk 250.

Next, a disk determination apparatus and method using a push-pull signal will be described in detail with reference to FIGS. 1 and 2.

First, a disc determination apparatus using a push pull signal will be described with reference to FIG. 1. When the user command requesting the disc determination is applied, the system controller 140 provides the RF signal and servo error signal processing unit 120 with a command to turn on the power of the laser diode 113. It is required to execute the focus servo operation mode for disc determination.

Accordingly, the RF signal and servo error signal processor 120 provides power for driving the laser diode 113 through an auto laser power control (ALPC) that automatically controls the power of the laser diode 113. . FIG. 1 may be configured to include an ALPC in the RF signal and servo error signal processing unit 120 or to exist outside the RF signal and servo error signal processing unit 120.

The servo unit 130 may move up or down the objective lens 111 by up or down of the focusing actuator 115 so that the pickup unit 110 may perform a focus operation on the optical disc 100. Make sure the signal surface of 100 is within the depth of focus.

Thereafter, the photo detector 114 detects the beam reflected by the beam splitter 112 and transmits the beam to the RF signal and the servo error signal processor 120.

The RF signal and servo error signal processor 120 generates a focus error signal FE and an RF SUM signal based on the amount of light detected by the photo detector 114. A method of generating a focus error using the detected amount of light and generating an RF SUM signal generates an RF SUM signal by adding signals detected by the four-segment photodetector 114 light receiving elements A to D. FIG.

The system controller 140 is a disk determination unit and generates a push-pull signal from the RF signal and the RF SUM signal output from the servo error signal processing unit 120. The push-pull signal is a difference signal between V1 and V2 obtained by subtracting the sum signals V1 and V2 of the radial pairs B, C, A, and D of each light receiving element output from the RF signal and the servo error signal processing unit 120. It is generated as (V2-V1). In general, the push-pull signal is used to generate a tracking error in the DPP method, but in other methods, it is used to determine whether the lens is at the pickup center.

The system controller 140 measures the peak-to-peak voltage of the generated push-pull signal and compares the peak-to-peak voltage of the push-pull signal with a reference voltage to determine the type of the optical disk 100.

When the optical disc 100 is a DVD-ROM, since the depth of the pit is shallower than that of the DVD-R, the peak-to-peak voltage of the push-pull signal is smaller than the reference voltage. Therefore, the system controller 140 compares the peak-to-peak voltage of the push-pull signal with the reference voltage, so that the optical disk 100 is a DVD-ROM disc when the peak-to-peak voltage of the push-pull signal is smaller than the reference voltage. Determine if

For dinner, when the optical disc 100 is a DVD-R, since the depth of the pit is deeper than that of the DVD-ROM, the peak-to-peak voltage of the push-pull signal becomes larger than the reference voltage. Therefore, the system controller 140 compares the peak-to-peak voltage of the push-pull signal with the reference voltage, so that the optical disk 100 is a DVD-R disc when the peak-to-peak voltage of the push-pull signal is larger than the reference voltage. Determine if

When the optical disc 100 is determined to be a DVD-R or a DVD-ROM, the system controller 140 outputs a servo control signal for proper servo operation to the optical disc 100 to the servo unit 130.

Next, a disc determination method using a push pull signal will be described with reference to FIG. 2. When the system controller 140 receives a user command for disc determination, the system controller 140 turns on the servo operation for disc determination (step 200). The system controller 140 executes the focus servo operation mode for disc determination by the servo unit 130 while providing a command to the RF signal and servo error signal processing unit 120 to turn on the power of the laser diode 113. Require. Accordingly, the RF signal and servo error signal processor 120 provides power for driving the laser diode 113 through an ALPC that automatically controls the power of the laser diode 113. The servo unit 130 may move up or down the objective lens 111 by up or down of the focusing actuator 115 so that the pickup unit 110 may perform a focus operation on the optical disc 100. Make sure the signal surface of 100 is within the depth of focus. Thereafter, the photo detector 114 detects the beam reflected by the beam splitter 112 and transmits the beam to the RF signal and the servo error signal processor 120.

The RF signal and the servo error signal processor 120 generate RF SUM signals based on the amount of light detected by the photo detector 114, and the system controller 140 generates a push-pull signal from the RF SUM signal and generates a push-pull signal. The peak-to-peak voltage is measured (step 210). The RF signal and the servo error signal processor 120 generate the RF SUM signal by adding the signals detected by the four-segment photodetector 114 light receiving elements A to D, and the system controller 140 generates the RF signal and the servo error. The push-pull signal as the difference signal (V2-V1) of V1 and V2 obtained by subtracting the sum signals (V1, V2) of the radial pairs (B, C, A, D) of each light receiving element output from the signal processing unit (120). Create

The system controller 140 determines whether the peak-to-peak voltage of the push-pull signal is greater than the reference value (step 220). Since the depth of the pit is shallower than that of the DVD-R when the optical disc 100 is a DVD-ROM, the peak-to-peak voltage of the push-pull signal is smaller than the reference voltage, and the optical disc 100 is a DVD-R. Since the depth of the pit is deep compared to the DVD-ROM, the peak-to-peak voltage of the push-pull signal is larger than the reference voltage.

Therefore, when the peak-to-peak voltage of the push-pull signal is larger than the reference value, the optical disc 100 determines that the DVD-R disc is a step (230).

Similarly, if the peak-to-peak voltage of the push-pull signal is greater than the reference voltage, it is determined that the optical disk 100 is a DVD-R disk (step 240).

When the optical disc 100 is determined to be a DVD-R or a DVD-ROM, the system controller 140 sets a servo control signal for proper servo operation with respect to the optical disc 100 and outputs it to the servo unit 130. (Step 250).

So far I looked at the center of the preferred embodiment for the present invention. Those skilled in the art will appreciate that the present invention can be implemented in a modified form without departing from the essential features of the present invention. Therefore, the disclosed embodiments should be considered in descriptive sense only and not for purposes of limitation. The scope of the present invention is shown in the claims rather than the foregoing description, and all differences within the scope will be construed as being included in the present invention.

As described above, according to the present invention, by determining that the media type is DVD-R or DVD-ROM by using the push-pull signal, it is possible to implement proper servo operation and function implementation for the corresponding disk and to improve stability. Create.

1 is a block diagram showing the configuration of a disc determination device using a push pull signal according to the present invention.

2 is a flowchart illustrating an operation of a disc determination method using a push-pull signal according to the present invention.

Claims (6)

Pick-up unit for detecting the amount of beam reflected from the optical disk; An RF signal processor configured to generate an RF SUM signal based on the detected beam amount; And It is determined by generating a push-pull signal from the RF SUM signal and measuring peak-to-peak voltage and comparing the peak-to-peak voltage with a reference voltage to determine whether the optical disk is a DVD-R disk or a DVD-ROM disk. Disc determination apparatus using a push-pull signal including a system control unit for outputting a servo operation control signal corresponding to the disc. The method of claim 1, wherein the system control unit And determining that the optical disc is a DVD-R disc having a deeper pit depth when the peak-to-peak voltage is greater than a reference voltage. The method of claim 1, wherein the system control unit And determining that the optical disk is a DVD-ROM disk having a shallower pit depth when the peak-to-peak voltage is smaller than a reference voltage. (a) generating a push-pull signal from the RF SUM signal when the servo is operated and measuring the peak-to-peak voltage of the push-pull signal; And and (b) comparing the peak-to-peak voltage with a reference voltage to determine whether the optical disk is a DVD-R disk or a DVD-ROM disk. The method of claim 1, wherein in step (b) And the optical disc is determined to be a DVD-R disc having a deeper pit depth if the peak-to-peak voltage is greater than a reference voltage. The method of claim 1, wherein in step (b) And if the peak-to-peak voltage is less than a reference voltage, the optical disk is determined to be a DVD-ROM disk having a shallower pit depth.