Multi-wavelength Plasma Pumping for High Brightness
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing plasma light sources struggle to achieve higher temperatures and brightness, as increasing laser power tends to enlarge the plasma rather than increase its core temperature effectively.
Innovation Solution
The method involves focusing two different wavelengths of electromagnetic radiation into a gas volume, where the first wavelength creates a relatively colder plasma region and the second wavelength, absorbed by a hotter gas species, forms a hotter plasma region within the first, achieving higher temperatures and brightness.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If the power of the laser is increased to sustain the plasma, then the plasma grows larger, but the core temperature of the plasma does not increase appreciably
Solution Approach 1:
The plasma is divided into multiple regions with different temperatures by using multiple laser wavelengths. The first wavelength creates a larger, cooler outer plasma region, while the second wavelength creates a smaller, hotter core region. This segmentation allows independent control of plasma size and core temperature, resolving the contradiction between increasing temperature and controlling size.
Solution Approach 2:
Different regions of the plasma are given different thermal properties through selective wavelength absorption. The outer region absorbs the first wavelength and maintains a lower temperature, while the core region absorbs the second wavelength and achieves higher temperature. This local differentiation of thermal quality enables the plasma to have both large overall size and high core temperature simultaneously.
2Illumination intensity
If a single wavelength is used to pump the plasma, then the plasma can be sustained, but the brightness and temperature are limited
Solution Approach 1:
Multiple laser wavelengths are combined and focused into the same gas volume to create a multi-region plasma structure. The first wavelength sustains the outer plasma region while the second wavelength creates the hot core region. This merging of multiple light sources into a single plasma volume increases overall brightness and temperature without requiring separate physical light sources for each function.
Solution Approach 2:
The plasma serves multiple functions simultaneously: the outer region provides plasma sustainment and confinement, while the core region provides high-temperature radiation for illumination. This multi-functionality allows a single plasma structure to achieve both sustainability and high brightness, reducing the need for additional separate systems.
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 enables the creation of a hotter, smaller plasma region within a colder plasma region, enhancing the brightness and temperature of the plasma light source, which is essential for advanced integrated circuit inspection and fabrication.
Implementation Method 1
focusing a first wavelength of electromagnetic radiation into a gas within a volume, where the first wavelength is substantially absorbed by a first species of the gas and excites the first species of the gas into a first region of a plasma
Implementation Method 2
excites the first species of the gas into a first region of a plasma having a first size and a first temperature
Implementation Method 3
focusing a second wavelength of electromagnetic radiation into the first region of the plasma, where the second wavelength is different than the first wavelength and is substantially absorbed by a second species of the gas and excites the second species of the gas into a second region of the plasma within the first region of the plasma
Implementation Method 4
excites the second species of the gas into a second region of the plasma within the first region of the plasma having a second size that is smaller than the first size and a second temperature that is greater than the first temperature
Data Source
AI summary
A method of sustaining a plasma, by focusing a first wavelength of electromagnetic radiation into a gas within a volume, where the first wavelength is substantially absorbed by a first species of the gas and delivers energy into a first region of a plasma having a first size and a first temperature. A second wavelength of electromagnetic radiation is focused into the first region of the plasma, where the second wavelength is different than the first wavelength and is substantially absorbed by a second species of the gas and delivers energy into a second region of the plasma region within the first region of the plasma having a second size that is smaller than the first size and a second temperature that is greater than the first temperature.