Optical Disc Recording Pulse Compensation via Edge Shift Measurement
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional methods for optimizing recording pulse conditions in optical information recording media are time-consuming and require multiple trial writings, leading to prolonged latency and increased processing time, especially when adapting to new discs or power cycles.
Innovation Solution
A method that generates multiple sets of recording pulses with varying mark lengths and phases, measures edge shifts, and calculates compensation values using linear approximation to reduce the number of trial writings and optimize recording pulse conditions efficiently.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If multiple trial writings are performed to optimize recording pulse conditions, then recording quality is improved, but time required for learning and adapting increases
Solution Approach 1:
The patent performs preliminary trial writings to measure edge shifts and calculate compensation values before actual data recording. By pre-determining the optimal recording pulse conditions through trial writings and storing compensation values, the system avoids repeated trial writings during normal operation, thus reducing time loss while ensuring recording quality.
Solution Approach 2:
The patent implements a feedback mechanism where edge shifts are measured from trial writings, compensation values are calculated based on these measurements, and then recording pulse conditions are adjusted according to these compensation values. This closed-loop feedback system enables the system to learn optimal conditions efficiently and apply them to subsequent recording operations, resolving the contradiction between quality optimization and time consumption.
2Loss of time
If the number of trial writings is reduced to shorten learning time, then latency is reduced, but recording quality may deteriorate
Solution Approach 1:
The patent changes parameters of recording pulse conditions based on measured edge shifts from trial writings. By calculating compensation values that adjust pulse width, amplitude, or timing parameters, the system optimizes recording quality with minimal trial writings, thus reducing latency while maintaining high recording quality through parameter optimization rather than repeated trials.
3Reliability
If recording pulse conditions are optimized for each combination of mark lengths and space lengths, then thermal interference between marks is compensated, but device complexity increases
Solution Approach 1:
The patent segments the recording pulse control into separate adjustable parameters (pulse width, amplitude, timing) that can be independently optimized. Instead of controlling entire pulse trains as a single complex unit, the system divides the control into manageable segments that can be adjusted based on mark length and space length combinations, reducing device complexity while maintaining effective thermal interference compensation.
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
This approach significantly reduces the time required to learn and adapt recording pulse conditions, improving recording quality and reducing latency by minimizing the number of trial writings and optimizing pulse conditions quickly.
Implementation Method 1
information is rewritten as follows by using laser light. First, an information reproducing apparatus reads out a recording pulse standard condition from a calibration area of an optical disc
Implementation Method 2
In a phase change optical disc, heat of the applied laser light forms an amorphous area (mark) and an optical reflectance changes
Implementation Method 3
sizes of a mark to be formed and a space (an area between marks) are small. Thus, the heat of the laser light applied for forming a mark is conducted not only to that mark but also to marks on front and back sides via the spaces
Data Source
AI summary
A specific recording pattern is sequentially written onto an optical disc using each of three sets of recording pulse conditions as trial writing. The recording patterns are reproduced sequentially. Edge shift amounts of a mark which corresponds to each of three sets of recording pulse conditions are measured from a reproduction signal. Compensation values for the recording pulse conditions are obtained from calculation by linear approximation based on the measured values.