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Apparatus for and method of playing back optical disc

Imported: 23 Feb '17 | Published: 22 Oct '02

Masayuki Horita

USPTO - Utility Patents

Abstract

An optical disc playback apparatus selectively plays back a plurality of optical discs having different numbers of recording layers and/or different positions of recording layers in the thickness direction of the optical disc. In the optical disc playback apparatus, a light beam is applied to a loaded optical disc, and reflected light from the optical disc upon application of the light beam is detected. A signal is generated based on the reflected light which is detected, and the number of peaks of the generated signal and timings at which the peaks are outputted are detected. The type of the loaded disc is determined based on the detected number of peaks and/or the detected timings.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a perspective view of a single-layer disc;

FIG. 1B is a perspective view of a multi-layer disc;

FIG. 2A is a cross-sectional view of a related art CD-DA;

FIG. 2B is a cross-sectional view of a single-layer HD disc;

FIG. 2C is a cross-sectional view of a hybrid disc comprising a multi-layer disc having a recording layer in which CD data are recorded and another recording layer in which HD data are recorded;

FIG. 2D is a cross-sectional view of a multi-layer HD disc comprising a bonded multi-layer disc having recording layers in which HD data are recorded;

FIG. 3A is a fragmentary cross-sectional view showing a recording layer of the related art CD-DA shown in FIG. 2A;

FIG. 3B is a fragmentary cross-sectional view showing a recording layer of the single-layer HD disc shown in FIG. 2B;

FIG. 3C is a fragmentary cross-sectional view showing the recording layers of the hybrid disc shown in FIG. 2C;

FIG. 3D is a fragmentary cross-sectional view showing the recording layers of the multi-layer HD disc shown in FIG. 2D;

FIG. 4 is a block diagram of a playback apparatus according to an embodiment of the present invention;

FIG. 5 is a detailed block diagram of the playback apparatus according to the embodiment of the present invention;

FIG. 6 is a block diagram of a circuit arrangement for carrying out a first process of disc determining operation which employs a PI signal;

FIG. 7A is a diagram illustrative of a PI signal produced by an RF circuit when a CD-DA is played back;

FIG. 7B is a diagram illustrative of a PI signal produced by the RF circuit when a single-layer HD disc is played back;

FIG. 7C is a diagram illustrative of a PI signal produced by the RF circuit when a hybrid disc is played back;

FIG. 7D is a diagram illustrative of a PI signal produced by the RF circuit when a multi-layer HD disc is played back;

FIG. 8 is a flowchart of a disc determining process of the playback apparatus according to the embodiment of the present invention;

FIG. 9 is a flowchart of a process subsequent to the disc determining process of the playback apparatus according to the embodiment of the present invention;

FIG. 10 is a block diagram of a circuit arrangement for carrying out a second process of disc determining operation which employs FE signals;

FIG. 11A is a diagram illustrative of an FE signal produced by an RF circuit when a CD-DA is played back;

FIG. 11B is a diagram illustrative of an FE signal produced by the RF circuit when a single-layer HD disc is played back;

FIG. 11C is a diagram illustrative of an FE signal produced by the RF circuit when a hybrid disc is played back;

FIG. 11D is a diagram illustrative of an FE signal produced by the RF circuit when a multi-layer HD disc is played back;

FIG. 12 is a block diagram of a circuit arrangement for carrying out a third process of disc determining operation which employs a TE signal;

FIG. 13A is a diagram illustrative of a TE signal produced by an RF circuit when a CD-DA is played back;

FIG. 13B is a diagram illustrative of a TE signal produced by the RF circuit when a single-layer HD disc is played back;

FIG. 13C is a diagram illustrative of a TE signal produced by the RF circuit when a hybrid disc is played back; and

FIG. 13D is a diagram illustrative of a TE signal produced by the RF circuit when a multi-layer HD disc is played back.

Claims

1. An apparatus for selectively playing back a plurality of optical discs including a first optical disc having a recording layer positioned substantially on a surface of said first optical disc, a second optical disc having a recording layer positioned substantially in a middle position between surfaces of said second optical disc, a third optical disc having a first recording layer positioned substantially in a middle position between surfaces of said third optical disc and a second recording layer positioned substantially on one of said surfaces of said third optical disc, and a fourth optical disc having first and second recording layers positioned substantially in a middle position between surfaces of said fourth optical disc, the apparatus comprising:

2. The apparatus according to claim 1, wherein said signal generated by said signal generating means comprises a playback signal from said one optical disc.

3. The apparatus according to claim 1, wherein said signal generated by said signal generating means comprises a focus error signal.

4. The apparatus according to claim 1, wherein said signal generated by said signal generating means comprises a tracking error signal.

5. The apparatus according to claim 1, wherein said playback condition set by said setting means comprises at least one of a wavelength of the light beam from the applying means, a servo constant, and a decoding process.

6. The apparatus according to claim 1, wherein said applying means comprises means for applying the light beam to an inner circumferential area of said one optical disc.

7. The apparatus according to claim 1, wherein said decision means comprises means for determining a number of recording layers of said one optical disc depending on said number of peaks detected by said detecting means.

8. The apparatus according to claim 1, wherein said decision means comprises means for determining positions of recording layers of said one optical disc depending on said timings detected by said detecting means.

9. An apparatus for selectively playing back one optical disc of a plurality of optical discs including a first optical disc having a recording layer positioned substantially on a surface of said first optical disc, a second optical disc having a recording layer positioned substantially in a middle position between surfaces of said second optical disc, a third optical disc having a first recording layer positioned substantially in a middle position between surfaces of said third optical disc and a second recording layer positioned substantially on one of said surfaces of said third optical disc, and a fourth optical disc having first and second recording layers positioned substantially in a middle position between surfaces of said fourth optical disc, the apparatus comprising:

10. The apparatus according to claim 9, wherein said recording layer of said first optical disc contains a recorded audio signal sampled at a sampling frequency of 44.1 kHz and quantized with sixteen bits.

11. The apparatus according to claim 9, wherein one of said first and second recording layers of one of said third and fourth optical discs contains a first recorded audio signal sampled at a sampling frequency fs (kHz) and quantized with multiple bits, and another of said first and second recording layers of one of said third and fourth optical discs contains a second recorded audio signal sampled at a sampling frequency fs×n (kHz) (n is a positive integer ≧2) and quantized with one bit.

12. A method of selectively playing back a plurality of optical discs including a first optical disc having a recording layer positioned substantially on a surface of said first optical disc, a second optical disc having a recording layer positioned substantially in a middle position between surfaces of said second optical disc, a third optical disc having a first recording layer positioned substantially in a middle position between surfaces of said third optical disc and a second recording layer positioned substantially on one of said surfaces of said third optical disc, and a fourth optical disc having first and second recording layers positioned substantially in a middle position between surfaces of said fourth optical disc, the method comprising the steps of:

13. The method according to claim 12, wherein said signal generated in said step of generating comprises a playback signal from the optical disc.

14. The method according to claim 12, wherein said signal generated in said step of generating comprises a focus error signal.

15. The method according to claim 12, wherein said signal generated in the step of generating comprises a tracking error signal.

16. The method according to claim 12, wherein said playback condition set in the step of setting comprises at least one of a wavelength of the applied light beam, a servo constant, and a decoding process.

17. The method according to claim 12, wherein said step of applying a light beam comprises the step of applying the light beam to an inner circumferential area of said one optical disc.

18. The method according to claim 12, further comprising the step of determining a number of recording layers of said one optical disc depending on said number of peaks detected in said first step of detecting.

19. The method according to claim 12, further comprising the step of determining positions of recording layers of said one optical disc depending on said timings detected in said second step of detecting.