Compact Laser Amplifier Architecture via Folded Cavity Design

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current high-power laser designs have large footprints and high costs, making them inefficient for compact, cost-effective applications such as Inertial Confinement Fusion and high-average-power operations.

Innovation Solution

A four-pass amplifier architecture that reduces the number of optics while increasing efficiency, allowing for compact designs with reduced beam distortion and deeper field depth, suitable for high peak and average power applications, using transverse or end pumping of amplifiers in a quad-beam configuration.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Power

If conventional high-power laser designs are used, then high power output is achieved, but system footprint and cost increase

Engineering Contradiction:
Improvelaser power outputVSAvoidsystem footprint
Core Design Contradiction:
PowerVSArea of stationary object

Solution Approach 1:

The patent transitions from conventional linear optical paths to a three-dimensional folded cavity architecture. The laser beam propagates through a closed-loop cavity that utilizes vertical and lateral spatial dimensions, allowing multiple passes through the gain medium within a compact footprint. This dimensional reorganization enables high power output without proportionally increasing system area.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

Solution Approach 2:

The patent implements a nested amplifier architecture where a first laser amplifier is positioned within or adjacent to a second laser amplifier. The optical cavity of the first amplifier is nested within the overall system structure, allowing shared optical components and reduced overall system footprint while maintaining high power output capabilities.

Inventive Principle:
Principle #7Nested doll (Nesting)

2Power

If conventional laser amplifier architectures are used, then high power is achieved, but device complexity and cost increase

Engineering Contradiction:
Improvelaser powerVSAvoidoptics quantity
Core Design Contradiction:
PowerVSDevice complexity

Solution Approach 1:

The patent employs optical components that serve multiple functions within the laser system. Mirrors and optical elements are designed to simultaneously perform beam steering, cavity formation, and amplification functions. The shared optical cavity serves both the first and second amplifiers, reducing the total number of components required while maintaining high power output.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Solution Approach 2:

The patent merges the optical cavities of multiple amplifiers into a shared closed-loop structure. Instead of separate cavities for each amplifier, a single integrated cavity allows the beam to traverse through multiple amplifier media in sequence, reducing component count and simplifying the overall device architecture while achieving high power output.

Inventive Principle:
Principle #5Merging (Combining)

3Area of stationary object

If compact laser designs are implemented, then footprint is reduced, but beam quality and field depth may deteriorate

Engineering Contradiction:
Improvesystem footprintVSAvoidbeam quality
Core Design Contradiction:
Area of stationary objectVSManufacturing precision

Solution Approach 1:

The closed-loop cavity architecture enables the laser beam to undergo multiple continuous passes through the gain medium without interruption or external realignment. This continuous circulation maintains beam coherence and quality while achieving high power output within a compact footprint, as the beam repeatedly interacts with the amplifying medium in a controlled manner.

Inventive Principle:
Principle #20Continuity of useful action

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 solution provides compact, high-efficiency laser systems capable of generating high power beams, suitable for Inertial Confinement Fusion and other applications, with reduced system costs and improved performance characteristics compared to conventional designs.

Implementation Method 1

a first amplifier head disposed along an optical amplification path adjacent a first end of the enclosure and a second amplifier head disposed along the optical amplification path adjacent a second end of the enclosure

Methodology Applied
Scientific EffectStimulated emission: Laser

Implementation Method 2

The beam is laterally shifted by a polarizer between the booster amplifier and the cavity amplifier, and reflected off a second cavity mirror

Methodology Applied
Scientific EffectReflection: Reflection

Data Source

PatentEP2614560B1Method and system for compact efficient laser architecture
Publication Date: 2023.05.31 LAWRENCE LIVERMORE NAT SECURITY LLC
  • EP2614560B1 patent drawingFigure 1A~1B
  • EP2614560B1 patent drawingFigure 1C
  • EP2614560B1 patent drawingFigure 2A~2B

AI summary

A laser amplifier module having an enclosure includes an input window, a mirror optically coupled to the input window and disposed in a first plane, and a first amplifier head disposed along an optical amplification path adjacent a first end of the enclosure. The laser amplifier module also includes a second amplifier head disposed along the optical amplification path adjacent a second end of the enclosure and a cavity mirror disposed along the optical amplification path.