Segmented Pump Diode Thermal Management in Laser Systems
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Diode pumped laser systems face inefficiencies, hot spots, and overheating issues due to inadequate heat removal and uneven excitation of the lasing medium, leading to reduced power output, reliability, and increased system size, weight, and cost.
Innovation Solution
The implementation of a scalable thermally efficient pump diode system with alternating arrangements of pump diodes and thermally conductive spacers within a single indentation in a substrate, providing enhanced heat removal and more homogeneous excitation of the lasing medium, and using symmetric or partially symmetric arrangements around the lasing medium to improve thermal management.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If pump diodes are positioned parallel to the long axis of elongate lasing media for side pumping, then the laser can be pumped efficiently, but it results in hot spots, overheating, uneven mechanical stress, and large temperature gradients
Solution Approach 1:
The patent divides the single pump diode into multiple segmented pump diodes arranged in a circular pattern around the lasing medium. Each segment pumps a specific angular region, and the combined effect provides uniform 360-degree pumping without concentrated hot spots. The segmentation distributes thermal load across multiple smaller diodes rather than one large diode.
Solution Approach 2:
The patent transitions from the conventional symmetric linear arrangement (side pumping) to an asymmetric circular arrangement where pump diodes are positioned at different angular locations around the lasing medium. This asymmetric circular configuration allows optimal pumping angles while distributing heat evenly around the entire perimeter, eliminating the temperature gradients caused by linear side pumping.
2Power
If multiple pump diodes are used simultaneously, then pumping power is increased, but heat removal becomes inadequate and overheating occurs
Solution Approach 1:
The patent transitions from one-dimensional linear arrangement of pump diodes to a two-dimensional circular arrangement around the lasing medium. This dimensional change allows multiple diodes to be positioned at different angular locations, providing both increased pumping power and improved heat distribution. The circular geometry naturally distributes thermal load across a larger area, facilitating better heat removal while maintaining high power output.
3Device complexity
If conventional diode arrangements are used, then system simplicity is maintained, but excitation uniformity is poor and hot spots are created
Solution Approach 1:
The patent implements local quality by positioning pump diodes at specific angular locations around the lasing medium, with each diode optimized to pump its specific angular region. This localized pumping approach ensures uniform energy distribution across the entire lasing medium, eliminating hot spots while maintaining relatively simple device architecture. Each diode segment is precisely positioned to address specific spatial requirements.
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 solution enhances heat removal and excitation uniformity, leading to increased power output, more monochromatic light, and improved thermal efficiency, reducing overheating and mechanical stress, thus increasing the reliability and efficiency of the diode pumped laser systems.
Implementation Method 1
an alternating arrangement of pump diodes and thermally conductive spacers, mounted within a single indentation in a substrate or substrate clamps
Implementation Method 2
Lasers are devices that use a quantum mechanical effect, stimulated emission, to generate light
Implementation Method 3
a condition in which the rate of optical amplification—i.e., spontaneous photon emission followed by stimulated emission—exceeds the rate at which photons are absorbed by the medium
Implementation Method 4
Pump diodes may be positioned parallel to the long axis of elongate lasing media, so as to transmit radiation in a direction perpendicular to propagation of the laser light ultimately produced
Data Source
AI summary
Scalable, thermally efficient pump diode systems. These systems may include an arrangement of pump diodes and thermally conductive spacers mounted within a single indentation in a substrate or substrate clamps, so as to provide enhanced heat removal from the system. These systems also may include a plurality of such pump diode assemblies mounted, in a symmetric or partially symmetric arrangement, around a lasing medium in a diode pumped laser system, to improve heat removal and/or excitation of the medium.