Optical Disc Readout Crosstalk Suppression via Adjacent Track Binary Signal

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Solution Overview

Problem

High-density optical discs face challenges in reducing crosstalk interference during data reproduction, leading to increased memory capacity and circuit size requirements in existing solutions.

Innovation Solution

An information processing device with a multi-input adaptive equalizer and an adjacent track reproduction binary signal supply unit that performs adaptive equalization and binarization processes to suppress crosstalk, using a split region-compatible five-signal output type photo detector to generate high-quality reproduction signals.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Object-affected harmful factors

If adaptive equalization is performed using read signals from adjacent tracks to remove crosstalk, then crosstalk suppression is improved, but memory capacity and circuit size increase

Engineering Contradiction:
Improvecrosstalk interferenceVSAvoidmemory capacity
Core Design Contradiction:
Object-affected harmful factorsVSQuantity of substance

Solution Approach 1:

The invention extracts only the essential binary signal information from adjacent tracks rather than storing complete read signals. By using an adjacent track reproduction binary signal supply unit that provides simplified binary representations instead of full analog/digital read signals, the system achieves crosstalk suppression while minimizing memory requirements.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The invention creates a simplified copy of the adjacent track signal in binary form rather than storing the complete original signal. This binary copying approach maintains the essential information needed for crosstalk cancellation while significantly reducing the data volume and memory capacity required.

Inventive Principle:
Principle #26Copying

2Object-affected harmful factors

If adaptive equalization is performed using read signals from adjacent tracks to remove crosstalk, then crosstalk suppression is improved, but circuit size increases

Engineering Contradiction:
Improvecrosstalk interferenceVSAvoidcircuit size
Core Design Contradiction:
Object-affected harmful factorsVSDevice complexity

Solution Approach 1:

The invention extracts only the essential binary signal information from adjacent tracks rather than storing complete read signals. By using an adjacent track reproduction binary signal supply unit that provides simplified binary representations instead of full analog/digital read signals, the system achieves crosstalk suppression while minimizing memory requirements.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The invention creates a simplified copy of the adjacent track signal in binary form rather than storing the complete original signal. This binary copying approach maintains the essential information needed for crosstalk cancellation while significantly reducing the data volume and memory capacity required.

Inventive Principle:
Principle #26Copying

3Quantity of substance

If high-density recording is performed by reducing channel bit length, then recording density is improved, but inter-symbol interference increases

Engineering Contradiction:
Improverecording densityVSAvoidinter-symbol interference
Core Design Contradiction:
Quantity of substanceVSLoss of information

Solution Approach 1:

The invention employs feedback mechanisms through adaptive equalization that uses binary signals from adjacent tracks to cancel crosstalk interference. This feedback approach continuously adjusts to compensate for inter-symbol interference caused by high-density recording, maintaining signal quality despite reduced channel bit lengths.

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The invention converts the harmful crosstalk and inter-symbol interference effects into useful information by using the same adjacent track signals that cause interference as the basis for cancellation. The binary reproduction signals from adjacent tracks, which initially represent interference sources, are transformed into corrective feedback signals that eliminate the harmful effects.

Inventive Principle:
Principle #22Blessing in disguise (Convert harm into benefit)

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The solution enables high-quality data reproduction from high-density optical discs with reduced memory capacity and circuit size, effectively suppressing crosstalk interference.

Implementation Method 1

a photo detector that outputs a readout signal from a reproduction track of an information recording disc

Methodology Applied
Scientific EffectPhotoelectric Effect: Photoelectric Effect

Data Source

PatentEP3413313B1Information processing device, information processing method, and program
Publication Date: 2022.03.02 SONY GROUP CORP
  • EP3413313B1 patent drawingFigure 1
  • EP3413313B1 patent drawingFigure 2
  • EP3413313B1 patent drawingFigure 3

AI summary

Provided are a device and a method which are capable of performing crosstalk-removed high-quality data reproduction from a high-density recording type optical disc. The device includes a photo detector that outputs a readout signal from a reproduction track of an information recording disc, an adj acent track reproduction binary signal supply unit that outputs a binary signal (binary data) which is a reproduction signal of an adjacent track of the reproduction track, a multi-input adaptive equalizer that includes an equalizer unit that receives the readout signal from the reproduction track and an adjacent track reproduction binary signal and outputs an equalization signal by an adaptive equalization process based on an input signal, and a binarization processing unit that executes a binarization process based on the equalization signal and generates a reproduction signal of the reproduction track.