Dual Fluorescent Wheel Internal Cooling for Laser Heat Dissipation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Previous fluorescent wheels suffer from inadequate cooling, leading to degradation of luminous material under excitation-laser radiation, especially when coated on both sides, as heat dissipation is reduced and additional heating occurs due to the radiation on the rear coated surface.
Innovation Solution
An internally cooled fluorescent device, known as the dual fluorescent wheel, featuring two disk-like carrier elements with luminous material on the outside surfaces and internal ventilation for forced cooling, utilizing air flow through openings to dissipate heat effectively, and optionally using cooling ribs and a pre-cooled medium for enhanced heat management.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If the fluorescent wheel is coated on both sides to increase light output, then the illumination intensity is improved, but the heat dissipation is reduced and additional heating occurs due to excitation-laser radiation on the rear coated surface
Solution Approach 1:
The fluorescent wheel is divided into two separate disk-like carrier elements arranged at a mutual distance, creating an internal interspace. This segmentation allows one side of each carrier element to be coated with luminous material for light output while the other side remains uncoated or differently coated, enabling differential heat management and preventing excessive heating on both surfaces simultaneously.
Solution Approach 2:
A cooling medium (air or gas) is introduced as an intermediary substance flowing through the internal interspace between the two carrier elements. This cooling medium actively removes heat from the luminous material on both sides by convection, preventing temperature buildup while allowing both sides to be coated for maximum light output.
2Illumination intensity
If the excitation-laser power density is increased to improve illumination intensity, then the light output is improved, but the luminous material degrades faster due to inadequate cooling
Solution Approach 1:
A forced convection cooling system using pneumatic principles is implemented, where a cooling medium (air or gas) is actively circulated through the internal interspace of the fluorescent wheel. This pneumatic cooling system efficiently removes heat generated by high-power excitation-laser radiation, allowing high illumination intensity to be maintained without degrading the luminous material, thus extending its operational lifespan.
3Reliability
If a freely rotating fluorescent wheel is used to prevent permanent local damage, then the reliability is improved, but the device complexity increases due to rotation mechanisms
Solution Approach 1:
The fluorescent wheel is segmented into two separate carrier elements with an internal interspace between them. This segmentation enables the incorporation of a cooling medium flow path through the interior, allowing active cooling without requiring complex external rotation mechanisms. The two-carrier structure provides redundancy and heat distribution while simplifying the overall cooling system design.
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 dual fluorescent wheel effectively prolongs the lifespan of the luminous material by actively cooling the inside surfaces during rotation, allowing for high excitation-laser power densities without permanent damage, suitable for applications requiring intense illumination like video projection and medical endoscopy.
Implementation Method 1
During the rotation of the dual fluorescent wheel, the ambient air or possibly another cooling medium flows in through the at least one opening into the interspace between the two disk-like carrier elements and essentially radially toward the outside, as a result of which the inside surfaces are cooled actively by the cooling air flowing past.
Implementation Method 2
at least one conversion area (4, 5) which contains luminous material and is arranged on at least one of the two outside surfaces (2a, 3a) for converting the excitation-laser radiation into converted light
Data Source
AI summary
A dual fluorescent wheel with two disk-shaped carrier elements which are interconnected by wing-type cooling ribs is disclosed. When the dual fluorescent wheel rotates, air flows in through an axial opening in one of the carrier elements, the air flows radially through the interspace between the carrier elements or the wing-type cooling ribs and flows out at the edge. This airflow improves the dissipation of heat which is produced when an excitation laser irradiates the annular fluorescent strips located on the two exterior faces.