JPH09293322A - Disk discriminator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a disk discriminator capable of automatically discriminating whether a set disk is a CD or a DVD(a digital video disk) so far as the disk is set at the correct place of a disk reproducer, even when an operator does not recognize the kind of the disk to be reproduced. SOLUTION: An optical pickup 25 is set at the innermost place of a disk 10, and the optical pickup 25 is moved to the outer circumference of the disk 10 for a predetermined time from the innermost place. The disk to be detected to is discriminated as a CD when focussing is conducted when a servo is set for the CD mode, and the disk to be detected 10 is distinguished as a DVD when focussing is performed when the servo is set for the DVD mode.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disc discriminating apparatus for discriminating whether a disc mounted on a player is a CD or a DVD.

[0002]

2. Description of the Related Art At present, a CD is widely used as a music recording medium, an information recording medium, etc., but a DVD (Digital Video Disk) is attracting attention as a medium having a recording density much higher than this.

Since the reproduction principle itself is the same for both CD and DVD, it is possible to reproduce both of these discs by one reproducing device. But between the CD and the DVD,
Since the specifications such as the lead-in area start position and the data area start position are different from each other, the user needs to instruct whether the disc to be reproduced by the reproducing apparatus is a CD or a DVD. In accordance with the disc type instructed in this way, the playback device starts playback.

For example, the lead-in area start position is
It is 23.0 mm for CD and 22.6 m for DVD.
m, the data area start position is 25.0 for CD
mm, and 24.0 mm for DVD.

[0005]

However, CDs and DVDs
Since they have almost the same shape and their thicknesses are slightly different from each other, it is difficult for the user to discriminate the disc type at first glance.

Therefore, even if the disc to be reproduced is a DVD, it is sometimes instructed to the reproducing device that it is a CD. In this case, since the disc specifications are different, the disc cannot be reproduced. On the contrary, it may be instructed to the reproducing apparatus that the disc to be reproduced is a DVD even though it is a CD, and in this case also, since the disc specifications are different, the disc cannot be reproduced. As described above, there is a problem in that even if the disc is set in the disc reproducing apparatus at the correct position, the disc cannot be reproduced unless the type of the set disc is correctly specified.

According to the present invention, even if the operator does not recognize the type of the disc to be reproduced, as long as the disc is set in the correct position of the disc reproducing apparatus, whether the set disc is a CD or not. It is an object of the present invention to provide a disc discriminating apparatus capable of discriminating whether a disc is a DVD or not.

[0008]

According to the present invention, an optical pickup is set at the innermost peripheral position of a disc, and the optical pickup is moved to the outer periphery of the disc for a predetermined time from this innermost peripheral position, and the servo is used for a CD servo. If the focus is on when set to, it is determined that the detected disk is a CD, and if the servo is set to the DVD servo, the detected disk is DV.
It is determined to be D.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a block diagram showing a disc reproducing apparatus DS1 incorporating a disc discriminating apparatus 20 according to an embodiment of the present invention.

The disc reproducing device DS1 includes a disc discriminating device 20, an operation panel 31, a display 32, and
An RF signal processing unit 41, a digital signal control unit 42,
D / A conversion circuit 43, LPF 44, VRAM 45
And a display 46 and a microcomputer 47.

The disc discriminating device 20 includes a control unit 21 and
Focus servo 22, tracking servo 23,
It has a feed servo 24, an optical pickup 25, a spindle servo 26, and a spindle motor 27.

The control unit 21 controls the entire disc discriminating apparatus 20, and also has a focus servo 22, a tracking servo 23, a feed servo 24, and an optical pickup 2.
5. The spindle servo 26 is individually controlled.

The optical pickup 25 is a CD or a DVD.
A laser beam is radiated to the laser beam and information recorded on a CD or a DVD is detected based on the reflected beam.

The focus servo 22 controls the position of the optical pickup 25 so that optimum focus can be obtained according to the reflected beam received by the optical pickup 25. The tracking servo 23 is for applying a servo related to tracking. Feed servo 24
Is to apply a predetermined servo to the feed mode. The spindle servo 26 applies a predetermined servo to the spindle motor 27.

The RF signal processing section 41 includes an optical pickup 2
The EFM signal, the error signal, the CLV control signal and the like are created from the detection signal of No. 5. Digital signal control unit 4
2 performs synchronization, deinterleaving, error correction, etc. on the EFM signal output from the RF signal processing unit 41,
This is a part that demodulates audio sample data and subcode data.

Next, the operation of the above embodiment will be described.

FIG. 2 is a flow chart showing the operation of the disk discriminating apparatus 20 according to the above embodiment.

First, a CD or a DVD is set, the laser beam irradiation position of the optical pickup 25 is set to the innermost peripheral position of the disc (S1), and the optical pickup 25 is fixed from this position toward the outer periphery of the disc. By moving for a certain time, it is moved for a certain distance (S2).
In this way, by moving the laser beam irradiation position from the innermost peripheral position of the disk by a certain distance, it is possible to reliably move the laser beam irradiation position to the signal writing area in both CD and DVD.

Then, the servo for CD is set (S3),
Focus on the CD (S4). When setting the CD servo, the CD may be affected by external factors such as surface wobbling and vibration.
Unique gain characteristics, phase characteristics, etc. are calculated by calculation,
Set the servo. When the focus for the CD is applied (S5), it is determined that the disk to be detected is the CD (S6), and the reproduction process of the CD is executed (S7). In addition, FOK (FOCUS OK)
A focus detection signal is output from the focus tracking servo IC, and it is determined whether or not focus is applied by using this signal.

When the focus for the CD is applied (S
4) If the focus is not applied (S5), the DVD servo is changed and set (S11), and the DVD focus is applied (S12). When the DVD servo is set, gain characteristics, phase characteristics, and the like peculiar to the DVD are calculated by external factors such as surface wobbling and vibration, and the servo is set. At this time, if focus is applied (S1
3) Then, the disc to be detected is judged to be a DVD (S14), and the DVD reproducing process is executed (S15).
When focusing on a DVD (S12),
If the single layer is not focused, an attempt is made to focus with the double layer.

If neither the focus for CD nor the focus for DVD is obtained (S13), error processing is executed (S21).

In the above embodiment, even if the operator does not recognize the type of the disc to be reproduced, as long as the disc is set in the correct position of the disc reproducing apparatus, the set disc becomes a CD. Whether it is a DVD or a DVD can be automatically determined.

The control unit 21 and the feed servo 24 are
The innermost circumferential position setting means sets the optical pickup to the innermost circumferential position of the disc, and the optical pickup moving means moves the optical pickup from the innermost circumferential position to the outer circumference of the disc for a predetermined time. Further, the control unit 21, the focus servo 22, the tracking servo 23, and the feed servo 2
Reference numeral 4 is a CD servo setting means for setting the servo to the CD servo, and D for setting the servo to the DVD servo.
It is an example of a VD servo setting means. The control unit 21 and the focus servo 22 are examples of focus detection means,
If the focus is on when the servo is set to the CD servo, it is determined that the detection target disk is the CD, and if the focus is on when the servo is set to the DVD servo, the detection target is detected. Is an example of a disc discriminating means for discriminating that the disc is a DVD.

[0024]

According to the present invention, even if the operator does not recognize the type of the disc to be reproduced, as long as the disc is set in the correct position of the disc reproducing apparatus, the disc that is set can be reproduced. Is it a CD?
It is possible to automatically determine whether it is VD.

[Brief description of drawings]

FIG. 1 is a disk discriminating apparatus 20 according to an embodiment of the present invention.
FIG. 3 is a block diagram showing a disc reproducing device DS1 in which is incorporated.

FIG. 2 is a flowchart showing an operation of the disc discriminating apparatus 20.

[Explanation of symbols]

 10 ... Disk, 20 ... Disk discriminating device, 21 ... Control part, 22 ... Focus servo, 23 ... Tracking servo, 24 ... Feed servo, 25 ... Optical servo.

Claims (1)

[Claims] 1. An innermost circumferential position setting means for setting the optical pickup at the innermost circumferential position of the disc; and an optical pickup moving means for moving the optical pickup from the innermost circumferential position to the outer circumference of the disc for a predetermined time. ; Servo is C
CD servo setting means for setting the D servo; DVD servo setting means for setting the servo to the DVD servo; focus detecting means; focus when the servo is set to the CD servo In this case, the disc discriminating means discriminates that the disc to be detected is a CD, and discriminates that the disc to be detected is a DVD if the servo is focused when the servo is set to the DVD servo. And a disc discriminating apparatus.