Optical Disk Drive Laser Temperature-Based RF Current Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing RF current superimposition method for semiconductor laser diodes in optical disk drives increases the operating temperature, leading to higher read error rates and noise, degrading signal quality.
Innovation Solution
An optical information read/write apparatus that includes a temperature sensor and a control section to adjust the RF superimposed current based on temperature readings, optimizing the RF current levels to minimize read error rates and unwanted radiation noise within permissible limits.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If RF current is superimposed on the drive current for the semiconductor laser diode, then returning beam noise is reduced, but operating temperature increases leading to higher read error rates
Solution Approach 1:
The patent applies dynamics by making the RF superimposed current adjustable rather than fixed. The control section dynamically changes the RF current value based on detected operating temperature, allowing the system to adapt to temperature variations and maintain optimal performance while managing thermal effects.
Solution Approach 2:
The patent changes the parameter of RF superimposed current based on temperature conditions. By detecting operating temperature and adjusting the RF current accordingly, the system optimizes the balance between noise reduction and temperature management, preventing read error rate increase.
2Stability of the object's composition
If RF current is superimposed on the drive current, then laser beam stability is improved, but unwanted radiation noise increases
Solution Approach 1:
The system dynamically adjusts the RF superimposed current based on operating temperature detection. This dynamic control allows the system to maintain laser beam stability while managing unwanted radiation noise by optimizing RF current levels according to actual operating conditions.
Solution Approach 2:
The patent implements feedback by detecting the operating temperature and using this information to control the RF superimposed current. The control section receives temperature detection results and adjusts the RF current accordingly, creating a closed-loop system that balances laser stability and radiation noise.
3Reliability
If higher RF superimposed current is used, then read error rate decreases, but unwanted radiation noise exceeds permissible limits
Solution Approach 1:
The patent makes the RF superimposed current dynamically adjustable based on operating temperature. This allows the system to use higher RF current when temperature is low (improving read error rate) and reduce RF current when temperature rises (controlling radiation noise within permissible limits).
Solution Approach 2:
The system changes the RF current parameter according to temperature conditions detected by the temperature sensor. This parameter adjustment optimizes the trade-off between read error rate and unwanted radiation noise, ensuring compliance with radiation standards while maintaining data reading accuracy.
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 apparatus effectively reduces noise and read error rates, ensuring accurate data reading and writing by dynamically adjusting RF current levels in response to temperature changes, while keeping unwanted radiation noise within regulatory standards.
Implementation Method 1
The light beam to irradiate the information storage layer of an optical disk is emitted from a semiconductor laser diode as a light source
Implementation Method 2
a temperature sensor for detecting a temperature around the laser light source
Implementation Method 3
an RF circuit for adding RF superimposed current to the drive current
Data Source
AI summary
An optical information read/write apparatus according to the present invention includes: a light source 1 that emits a laser beam to access an information storage medium optically; a laser driver 51a for supplying drive current to a semiconductor laser as the light source 1; an RE superimposed current generator 51c for adding RE superimposed current to the drive current; a temperature sensor 35 for detecting a temperature around the light source 1; and a control section for switching the values of the RE superimposed current according to the temperature detected.