Recordable optical disk

Details Recordable optical disk Recordable optical disk

2002-04-29

2003-08-05

Young, W. R. (Department: 2655)

Dynamic information storage or retrieval

Storage medium structure

Optical track structure

C369S275400, C369S053210, C369S047120

Reexamination Certificate

active

06603732

ABSTRACT:

TECHNICAL FIELD
The present invention relates to an optical disk, and a recording/reproducing apparatus and a recording method, for the optical disk, in particular, relates to a circular optical disk in which record signals such as images or voices are ciphered and recorded in order to protect literary properties from illegal copies thereof, and to an apparatus for and a method of reproducing and/or recording the record signals from/to the optical disk.
BACKGROUND ART
In general, in a DVD (Digital Versatile Disk) on the market, in which a movie, music or the like is collected (recorded), data information such as an image, voice or the like is ciphered and recorded in order to protect literary properties from illegal copies thereof, namely in order to protect the copyright thereof. Thus, when the DVD is reproduced using a DVD reproducing apparatus, the DVD reproducing apparatus reproduces it by reading key information recorded in a control data area of the DVD, and deciphering the ciphered data information using the key information to reconstruct the original image voice or the like.
Hereinafter, a conventional DVD and a DVD reproducing apparatus of the above-mentioned type will be concretely described. Hereupon, a DVR-R (i.e. write-once DVD), which is an example of the DVD, will be described.
FIG. 4
is a perspective view showing a rough construction of a conventional DVD-R. In
FIG. 4
,
101
denotes a DVD-R.
102
denotes a main information area of the DVD-R
101
. Data information such as an image, voice or the like is generally ciphered and recorded in the main information area
102
.
103
denotes a control data area. The control data area
103
records disk production information and physical format information including key information for deciphering the data information recorded in the main information area
102
. Hereupon, the control data area
103
is located at a position of the inner periphery side in the DVD-R
101
. In the DVD-R
101
, a spiral groove with a wobble is formed from the inner periphery side to the outer periphery side over the both areas
102
,
103
. Thus, the data information is recorded in the recording layer of the groove. Hereupon, the address information, the disk recording condition or the like has been previously recorded on the substrate in the form of an inter-groove pre-pit.
FIG. 5
is a block diagram showing a rough construction of a conventional DVD reproducing apparatus. In
FIG. 5
,
101
denotes the DVD
101
. The DVD
101
records the data information such as an image or voice to be reproduced.
104
denotes an optical pickup. The optical pickup
104
reads record signals of the DVD
101
using laser rays.
105
denotes a transfer controller. The transfer controller
105
moves the optical pickup
104
in the radial direction of the DVD
101
in order to read the record signals at arbitrary positions on the DVD
101
.
106
denotes a disk motor. The disk motor
106
rotates the DVD
101
.
107
denotes a first control circuit. The first control circuit
107
controls the optical pickup
104
, the transfer controller
105
and the disk motor
106
.
108
denotes an amplifier. The amplifier
108
amplifies the signals, which have been read by the optical pickup
104
.
109
denotes a second control circuit. The output signals of the amplifier
108
are inputted into the second control circuit
109
. Based on the signals, the second control circuit
109
generates servo signals such as focus error signals, tracking error signals or the like, which are required when the optical pickup
104
reads the record signals of the DVD
101
, and then outputs them to the first control circuit
107
. Meanwhile, the second control circuit
109
digitizes (makes binary) the input signals of analog type.
110
denotes a demodulation circuit. The demodulation circuit
110
analyzes the signals, which have been read from the DVD
101
to be digitized, while it reconstructs the data information such as the original image or music.
111
denotes a system control circuit. The system control circuit
111
wholly controls the DVD reproducing apparatus.
Hereinafter, actions of the DVD reproducing apparatus having the above-mentioned construction will be described. When the DVD
101
on the market is reproduced, at first, the first control circuit
107
drives and controls the transfer controller
105
in accordance with the instruction of the system control circuit
111
. As the result, the transfer controller
105
moves the optical pickup
104
to a position of an inner periphery side in the DVD
101
. The signals, which have been read by the optical pickup
104
, are amplified by the amplifier
108
, and then digitized by the second control circuit
109
. The demodulation circuit
110
reads the contents of the digital signals, and then sends the results to the system control circuit
111
. If the read contents do not include the key information in the control data area
103
(see FIG.
4
), the system control circuit
111
outputs another instruction to the first control circuit
107
again, and then causes the first control circuit
107
to drive and control the transfer controller
105
. As the result, the transfer controller
105
moves the optical pickup
104
to a further inner position of the inner periphery side in the DVD
101
, and then searches the key information of the DVD
101
.
The key information, which has beer recorded in the control data area
103
located at a position of the inner periphery side in the DVD
101
, is found out by repeating the above-mentioned actions. Then the demodulation circuit
110
reads the key information. If the system control circuit
111
detects that the demodulation circuit
110
has read the key information of the DVD
101
, the first control circuit
107
drives and controls the transfer controller
105
in accordance with the instruction of the system control circuit
111
. As the result, the transfer controller
105
moves the optical pickup
104
to a position of he outer periphery side in the DVD
101
. Then the optical pickup
104
reads the data information recorded in the main information area
102
of the DVD
101
(see FIG.
4
). Because the data information is generally ciphered, normal image or voice signals cannot be obtained if the data information is simply reproduced. However, the data information can be deciphered if the key information, which was recorded in the control data region
103
and has been previously read, is used. Thus, the demodulation circuit
110
deciphers the data information in the main information area
102
using the key information, which has been read, so as to reconstruct the original and normal image data or voice data.
However, in the writable optical disk such as a DVD-R or the like, there may be such a problem that a copy of the optical disk may be easily produced by copying the information in the control data area as well as the data information into the DVD-R, even if the data information is ciphered as described above. Thus, in order to physically prevent the information in the control data area from being copied as described above, there has been proposed such a procedure as to previously record other signals at least into the region, in which the key information of the DVD-R is to be recorded, so as to prevent the key information from being copied into the region. That is such a procedure as to prevent the normal key information from being reproduced by the reproducing apparatus by previously forming pre-nits with other information, for example by forming embossment in the control data area including the region in which the key information of the DVD-R is to be recorded, so as to destroy the normal key information.
However, in the conventional optical disk and the reproducing or recording system thereof as described above, it is impossible to record the physical format information and disk production information such as last address information etc of the writing region, into which data must be written later, into the control data area
103
, when the data

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