US 8,483,028 B2Granted

Method for adjusting recording condition, optical disc device, and information recording method

AssigneeHitachi Consumer Electronics Co., Ltd.

InventorsTakahiro Kurokawa, Hiroyuki Minemura

Life of this patent

Estimating the term…

Abstract

Provided is a recording adjustment method capable of controlling an edge position of a mark with high accuracy. Based on the acquired read-out signal waveform, a starting position of a last pulse is adjusted such that a so-called L-SEAT shift value for an end edge of the mark becomes minimum.

Claims7

Dependent claims

An optical disc device for reading out information by using a PRML procedure, the information being recorded by using codes whose minimum run length is 2T,

the optical disc device comprising:
means of binarizing each of read-out signal waveforms acquired from the optical disc by using the PRML procedure so as to obtain each of first binarized bit arrays;
means of generating a second binarized bit array and a third binarized bit array by shifting an edge of interest in each of the first binarized bit arrays by 1T leftward and rightward, respectively, wherein the second binarized bit array and the third binarized bit array are generated by calculating the first binarized bit array using exclusive OR (XOR) mask bit arrays, and the mask bit arrays include two kinds or more, at least one of which has a hamming distance of 2;
means of generating a first target signal waveform, a second target signal waveform and a third target signal waveform corresponding to each of the first binarized bit arrays, each of the second binarized bit arrays and each of the third binarized bit arrays, respectively;
means of calculating a first value equivalent to a difference between a Euclidean distance from the second target signal waveform to the read-out signal waveform and a Euclidean distance from the first target signal waveform to the read-out signal waveform, and a second value equivalent to a difference between a Euclidean distance from the third target signal waveform to the read-out signal waveform and a Euclidean distance from the first target signal waveform to the read-out signal waveform;
means of calculating a shift evaluation value of the edge of interest by using a differential value between the first value and the second value;
and
means of using a pulse string including (N−1) pulses for forming a recorded mark having a length of NT, where N is an integer, and of adjusting a starting position of a last pulse in the pulse string so as to minimize the shift evaluation value of the edge.

5 more elements

A method for adjusting a recording condition on an optical disc for writing information by using codes whose minimum run length is 2T, and for reading out the information by using an adaptive equalization procedure and a PRML procedure,

the PRML procedure including a PR(1, 2, 2, 2, 1)ML method,
the method for adjusting a recording condition comprising:
a step of binarizing each of read-out signal waveforms acquired from the optical disc by using the PRML procedure so as to obtain each of first binarized bit arrays;
a step of generating a second binarized bit array and a third binarized bit array by shifting an edge of interest in each of the first binarized bit arrays by 1T leftward and rightward, respectively;
a step of generating a first target signal waveform, a second target signal waveform and a third target signal waveform corresponding to each of the first binarized bit arrays, each of the second binarized bit arrays and each of the third binarized bit arrays, respectively;
a step of expressing
xL by
xL
=
1
2
⁢
(
1
-
ED
⁡
(
L
,
W
)
-
ED
⁡
(
T
,
W
)
ED
⁡
(
T
,
L
)
)
,
(
D1
)
xR by
xR
=
1
2
⁢
(
1
-
ED
⁡
(
R
,
W
)
-
ED
⁡
(
T
,
W
)
ED
⁡
(
T
,
R
)
)
,
(
D2
)
and an extended edge shift D by
D
=
xR
-
xL
2
where
W represents the read-out signal waveform, T represents the first target signal waveform, L represents the second target signal waveform, R represents the third target signal waveform, ED(a, b) (a and b are any one of W, T, R, L) represents a Euclidean distance among W, T, R and L, and xL represents an evaluation value for an error caused when the edge of interest is shifted leftward, xR represents an evaluation value for an error caused when the edge of interest is shifted rightward, and the extended edge shift D represents amount of an edge shift of the edge of interest, and
at least one of a Hamming distance between the second target signal waveform L and the first target signal waveform T, and a Hamming distance between the third target signal waveform R and the first target signal waveform T is 2 or greater, and the second target signal waveform L, the first target signal waveform T, and the third target signal waveform R satisfy run length restriction, and
calculating a shift evaluation value that is an statistical average A of the extended edge shifts Ds;
and
a step of using a pulse string including (N−1) pulses for forming a recorded mark having a length of NT, where N is an integer, and of adjusting a starting position of a last pulse in the pulse string so as to minimize the shift evaluation value of the edge.

88 more elements

An optical disc device for reading out information by using a PR(1, 2, 2, 2, 1)ML procedure, the information being recorded by using codes whose minimum run length is 2T,

the optical disc device comprising:
means of binarizing each of read-out signal waveforms acquired from the optical disc by using the PRML procedure so as to obtain each of first binarized bit arrays;
means of generating a second binarized bit array and a third binarized bit array by shifting an edge of interest in each of the first binarized bit arrays by 1T leftward and rightward, respectively;
means of generating a first target signal waveform, a second target signal waveform and a third target signal waveform corresponding to each of the first binarized bit arrays, each of the second binarized bit arrays and each of the third binarized bit arrays, respectively;
means of expressing
xL by
xL
=
1
2
⁢
(
1
-
ED
⁡
(
L
,
W
)
-
ED
⁡
(
T
,
W
)
ED
⁡
(
T
,
L
)
)
,
(
D1
)
xR by
xR
=
1
2
⁢
(
1
-
ED
⁡
(
R
,
W
)
-
ED
⁡
(
T
,
W
)
ED
⁡
(
T
,
R
)
)
,
(
D2
)
and an extended edge shift D by
D
=
xR
-
xL
2
where
W represents the read-out signal waveform, T represents the first target signal waveform, L represents the second target signal waveform, R represents the third target signal waveform, ED(a, b) (a and b are any one of W, T, R, L) represents a Euclidean distance among W, T, R and L, and xL represents an evaluation value for an error caused when the edge of interest is shifted leftward, xR represents an evaluation value for an error caused when the edge of interest is shifted rightward, and the extended edge shift D represents amount of an edge shift of the edge of interest, and
at least one of a Hamming distance between the second target signal waveform L and the first target signal waveform T, and a Hamming distance between the third target signal waveform R and the first target signal waveform T is 2 or greater, and the second target signal waveform L, the first target signal waveform T, and the third target signal waveform R satisfy run length restriction, and
calculating a shift evaluation value that is an statistical average Δ of the extended edge shifts Ds;
and
means of using a pulse string including (N−1) pulses for forming a recorded mark having a length of NT, where N is an integer, and of adjusting a starting position of a last pulse in the pulse string so as to minimize the shift evaluation value of the edge.

87 more elements

A method for recording data on an optical disc with codes whose minimum run length is 2T using a PRML procedure, including a step for adjusting a recording condition,

the method for adjusting a recording condition comprising:
a step of binarizing each of read-out signal waveforms acquired from the optical disc by using the PRML procedure so as to obtain each of first binarized bit arrays;
a step of generating a second binarized bit array and a third binarized bit array by shifting an edge of interest in each of the first binarized bit arrays by 1T leftward and rightward, respectively;
binarized bit arrays, respectively,
a step of expressing
xL by
xL
=
1
2
⁢
(
1
-
ED
⁡
(
L
,
W
)
-
ED
⁡
(
T
,
W
)
ED
⁡
(
T
,
L
)
)
,
(
D1
)
xR by
xR
=
1
2
⁢
(
1
-
ED
⁡
(
R
,
W
)
-
ED
⁡
(
T
,
W
)
ED
⁡
(
T
,
R
)
)
,
(
D2
)
and an extended edge shift D by
D
=
xR
-
xL
2
where
W represents the read-out signal waveform, T represents the first target signal waveform, L represents the second target signal waveform, R represents the third target signal waveform, ED(a, b)(a and b are any one of W, T, R, L) represents a Euclidean distance among W, T, R and L, and xL represents an evaluation value for an error caused when the edge of interest is shifted, xR represents an evaluation value for an error caused when the edge of interest is shifted rightward, and the extended edge shift D represents amount of an edge shift of the edge of interest, and
at least one of a Hamming distance between the second target signal waveform L and the first target signal waveform T, and a Hamming distance between the third target signal waveform R and the first target signal waveform T is 2 or greater, and the second target signal waveform L, the first target signal waveform T, and the third target signal waveform R satisfy run length restriction, and
calculating a shift evaluation value that is an statistical average of the extended edge shifts Ds;
a step of using a pulse string including (N−1) pulses for forming a recorded mark having a length of NT, where N is an integer, and of adjusting a starting position of a last pulse in the pulse string so as to minimize the shift evaluation value of the edge;
and
a step of recording data using the pulse string with said adjusting starting position of the last pulse.

88 more elements

Dependencies are inferred from the claim text.

Facts

Application: 13/516,011Filed 2 Mar 2010
Priority: JP 2010-00962720 Jan 2010
Published: US 2012/0250480 A14 Oct 2012
Granted: 9 Jul 2013
Term ends: Not estimatedThe source records don’t support an estimate.

Classification9 codes

G11B 7/00456
Recording: recording strategies, e.g. pulse sequences
G11B 7/0062
Overwriting: overwriting strategies, e.g. recording pulse sequences with erasing level used for phase-change media
G11B 7/126
Optical beam sources therefor, e.g. laser control circuitry specially adapted for optical storage devices; Modulators, e.g. means for…
G11B 20/10009
Digital recording or reproducing: improvement or modification of read or write signals

Family

US 2012/0250480 A1Pre-grant publication · published 4 Oct 2012
US 8,483,028 B2This patent

From the US filing history. Foreign family members aren’t listed.

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Abstract

An optical disc device for reading out information by using a PRML procedure, the information being recorded by using codes whose minimum run length is 2T,

the optical disc device comprising:
means of binarizing each of read-out signal waveforms acquired from the optical disc by using the PRML procedure so as to obtain each of first binarized bit arrays;
means of generating a second binarized bit array and a third binarized bit array by shifting an edge of interest in each of the first binarized bit arrays by 1T leftward and rightward, respectively, wherein the second binarized bit array and the third binarized bit array are generated by calculating the first binarized bit array using exclusive OR (XOR) mask bit arrays, and the mask bit arrays include two kinds or more, at least one of which has a hamming distance of 2;
means of generating a first target signal waveform, a second target signal waveform and a third target signal waveform corresponding to each of the first binarized bit arrays, each of the second binarized bit arrays and each of the third binarized bit arrays, respectively;
means of calculating a first value equivalent to a difference between a Euclidean distance from the second target signal waveform to the read-out signal waveform and a Euclidean distance from the first target signal waveform to the read-out signal waveform, and a second value equivalent to a difference between a Euclidean distance from the third target signal waveform to the read-out signal waveform and a Euclidean distance from the first target signal waveform to the read-out signal waveform;
means of calculating a shift evaluation value of the edge of interest by using a differential value between the first value and the second value;
and
means of using a pulse string including (N−1) pulses for forming a recorded mark having a length of NT, where N is an integer, and of adjusting a starting position of a last pulse in the pulse string so as to minimize the shift evaluation value of the edge.

5 more elements

Facts

Application

13/516,011Filed 2 Mar 2010

Priority

JP 2010-00962720 Jan 2010

Published

US 2012/0250480 A14 Oct 2012

Granted

9 Jul 2013

Term ends

Not estimatedThe source records don’t support an estimate.

Classification9 codes

G11B 7/00456
Recording: recording strategies, e.g. pulse sequences
G11B 7/0062
Overwriting: overwriting strategies, e.g. recording pulse sequences with erasing level used for phase-change media
G11B 7/126
Optical beam sources therefor, e.g. laser control circuitry specially adapted for optical storage devices; Modulators, e.g. means for…
G11B 20/10009
Digital recording or reproducing: improvement or modification of read or write signals