Fluorine Laser Electrodes with Current Return Tines
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In high-repetition rate gas discharge laser systems, uneven fluoride reef formation on electrodes leads to localized erosion and instability, causing pulse energy fluctuations and reducing the operating lifetime of anode and cathode surfaces.
Innovation Solution
The implementation of a fluorine gas discharge laser system with a mechanism to ensure uniform current density across electrodes, using current return tines to isolate the anode from the anode support bar and chamber walls, promoting longitudinal and lateral uniformity of the fluoride reef, and employing a coaxial cable with litz wire configuration to minimize skin effect and enhance current distribution.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If conventional coaxial cable is used for high voltage power connections in high-repetition rate pulsed power systems, then the system can deliver high power pulses, but the skin effect causes increased resistance and thermal management issues at high pulse repetition rates (6 kHz and greater)
Solution Approach 1:
The patent segments the solid center conductor into multiple parallel conductive elements (multiple rods or wires) within the coaxial cable structure. This segmentation increases the effective surface area for current flow, reducing the skin effect and associated energy losses at high pulse repetition rates while maintaining the cable's power delivery capability.
2Duration of action of stationary object
If fluoride layer forms unevenly on the anode surface, then the anode operating lifetime is extended, but local severe erosion of the opposing cathode surface occurs, leading to pulse energy instabilities
Solution Approach 1:
The patent modifies the local electrical properties at the electrode ends by adding inductance-enhancing mechanisms. This creates non-uniform current distribution along the electrode length, specifically reducing current density at the ends where streamer discharges typically initiate, thereby preventing cathode erosion and maintaining pulse energy stability while allowing the anode to operate for extended periods.
3Reliability
If current density is not uniform across the electrode discharge receiving region, then electrode erosion and streamer discharges occur, but achieving uniform current density requires complex electrode support and isolation mechanisms
Solution Approach 1:
The patent introduces current return tines as intermediary elements between the electrode and the chamber walls. These tines provide dedicated current return paths that isolate the electrode from direct contact with grounded surfaces, enabling more uniform current density distribution across the discharge receiving region without requiring complex isolation mechanisms.
4Object-generated harmful factors
If electrode ends have higher current density, then streamer (arc-like) discharges are reduced, but the overall current distribution uniformity deteriorates
Solution Approach 1:
The patent changes the electrical parameters (inductance and current distribution characteristics) of the electrode system by adding inductance-enhancing mechanisms at the electrode ends. This parameter modification creates a non-uniform current density profile that specifically suppresses streamer discharges at the ends while maintaining acceptable overall current distribution uniformity across the discharge region.
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 stabilizes the fluoride reef formation, reduces erosion and arcing, and enhances the operational stability and longevity of the electrodes, leading to improved pulse energy delivery and reduced thermal management issues in high-frequency applications.
Implementation Method 1
The fundamental (and harmonic) frequency of these pulses can often result in a skin effect applied to the coaxial cable conductors
Implementation Method 2
a fluoride layer generated on the anode in rare gas fluoride excimer lasers (a so-called reef) can greatly reduce the erosion rate
Data Source
AI summary
A apparatus and method are disclosed which may comprise a fluorine gas discharge laser system and electrode support system which may comprise a first electrode electrically connected to a source of high voltage; a first insulating mechanism insulating the first electrode from ground; a second electrode electrically insulated from the source of high voltage and together with the first electrode forming an elongated discharge region between portions of the first and second electrodes respectively extending along a longitudinal axis of each of the first and second electrodes, defining electrode discharge receiving region end portions; a plurality of current return tines electrically connected to the second electrode and to ground, the tines distributed along the longitudinal extent of the elongated discharge region; a second insulating mechanism electrically isolating the second electrode from ground except through the plurality of current return tines.