Optical disk having pattern for tilt detection

Details Optical disk having pattern for tilt detection Optical disk having pattern for tilt detection

1999-03-15

2001-11-06

Edun, Muhammad (Department: 2651)

Dynamic information storage or retrieval

With servo positioning of transducer assembly over track...

Optical servo system

C369S044280, C369S053190

Reexamination Certificate

active

06314067

ABSTRACT:

CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims the benefit of Korean Application No. 98-8646, filed Mar. 14, 1998, in the Korean Patent Office, the disclosure of which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an optical disk for an optical disk player, and more particularly, to an optical disk having a pattern which allows detection of degree of a tilt of disk.
2. Description of the Related Art
In a compact disk player or a digital video disk player, the tilt of a disk is a major factor in deteriorating reproduction of a signal. In particular, as the aperture ratio of an objective lens increases with increased density of a recording medium and the wavelength of a laser beam decreases, deterioration in performance due to the tilt becomes much greater. Accordingly, it is very important to correct the deteriorated performance due to the tilt of a disk having a high density recording medium.
To correct signal deterioration due to a tilt of a disk in an optical disk player, a shaft of a spindle motor is inclined, or a deck for installing a disk or optical pickup mechanisms for detecting a signal is inclined. For correction, it should be determined to what degree and in which direction a disk is inclined at the initial stage of disk reproduction.
A conventional tilt detection apparatus is shown in FIG.
1
and disclosed in U.S. Pat. No. 4,829,508. In the above tilt detection apparatus, an optical signal emitted from a light emitting diode
1
is projected to a disk
4
and the optical signal reflected by the disk
4
is received by two light receiving diodes
2
and
3
, to thereby detect the degree of tilt of a disk. That is, in the structure shown in
FIG. 1
, if the disk
4
is not tilted, the amplitudes of optical signals detected by the two light receiving diodes
2
and
3
are substantially the same. When the disk
4
is tilted, the amplitudes of optical signals detected by the two light receiving diodes
2
and
3
are different according to the degree of tilt. The degree of tilt is detected by a differential amplifier
5
for detecting the difference between the optical signals detected by the two light receiving diodes
2
and
3
. Here, the light emitting diode
1
and the light receiving diodes
2
and
3
are represented in the form of a photo-coupler
6
.
The conventional tilt detection apparatus having the above structure requires an additional optical mechanism, such as a photo-coupler, for detecting the degree of tilt. Also, an additional signal processing portion for detecting the tilt of a disk is needed. Further, since an offset of a detected signal according to the initial state of a mechanical structure and disk assembly is present, the degree of detection of a signal deteriorates.
SUMMARY OF THE INVENTION
To solve the above problems, it is an object of the present invention to provide an optical disk capable of detecting the tilt of a disk without an additional mechanism.
Additional objects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.
Accordingly, to achieve the above and other objects of the present invention, there is provided an optical disk on which a code train having a pit pattern or a mirror pattern is recorded on a concentrically or spirally formed track, wherein a tilt detection pattern having a predetermined code train is recorded at least in a partial area of the disk.


REFERENCES:
patent: 4663751 (1987-05-01), Kaku et al.
patent: 5627808 (1997-05-01), Hajjar et al.
patent: 5646919 (1997-07-01), Eastman et al.
patent: 5703855 (1997-12-01), Kirino et al.
patent: 0 397 354 a2 (1990-11-01), None
patent: 0 662 685 A1 (1995-07-01), None
patent: 6-96452 (1994-04-01), None
patent: 8-55341 (1996-02-01), None
patent: 8-279160 (1996-10-01), None
patent: WO 97/26651 (1997-07-01), None

Affiliated with

Also associated with

Rating

Optical disk having pattern for tilt detection does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Optical disk having pattern for tilt detection, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Optical disk having pattern for tilt detection will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2594115