Compact Closed-Loop Bypass Optical Beam Sensing for Alignment Drift

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing optical systems face challenges with beam-to-beam far-field alignment drift due to thermal issues and laser performance changes, leading to loss of target tracking and low-quality tracking, particularly in high-energy laser systems where HEL and TIL beams need to remain aligned on a target.

Innovation Solution

Implementing a compact closed-loop bypass optical beam sensing and correction system using spatial separation of optical beams, with divergence and steering control provided by refractive elements and reflective mirrors, and a closed-loop active control mechanism to maintain alignment.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If optical beams are transmitted through space without active control, then the system structure is simple, but beam alignment drift occurs due to thermal issues and laser performance changes

Engineering Contradiction:
Improvebeam alignment stabilityVSAvoidsystem structure complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent implements a closed-loop feedback control system where a sensor detects the actual position of the optical beam, compares it with the desired position, and generates error signals that drive actuators to correct alignment drift. This feedback mechanism continuously maintains beam alignment stability despite thermal variations and laser performance changes.

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The patent replaces complex mechanical alignment adjustment systems with an active control system using sensors, controllers, and actuators. Instead of relying on precise mechanical positioning that is susceptible to thermal drift, the system uses electronic sensing and actuation to dynamically correct beam position, reducing mechanical complexity while improving reliability.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

2Reliability

If traditional beam alignment control systems are implemented, then beam alignment can be maintained, but power consumption and electro-mechanical complexity increase

Engineering Contradiction:
Improvetarget tracking qualityVSAvoidpower consumption
Core Design Contradiction:
ReliabilityVSUse of energy by moving object

Solution Approach 1:

The patent employs dynamic control where actuators such as voice coil motors or piezoelectric elements continuously adjust mirror or lens positions in real-time to compensate for beam drift. This dynamic adjustment replaces static mechanical alignment, maintaining accurate target tracking while using minimal power through precision electronic actuation rather than continuous mechanical driving.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The control system automatically detects and corrects alignment errors without external intervention. The sensor-actuator loop operates autonomously to maintain beam alignment, eliminating the need for manual adjustment mechanisms and reducing overall system power requirements by using energy-efficient electronic control instead of power-intensive mechanical systems.

Inventive Principle:
Principle #25Self-service

3Adaptability or versatility

If spatial separation of optical beams is implemented, then beam alignment can be independently controlled, but device complexity increases

Engineering Contradiction:
Improveindependent beam control capabilityVSAvoidoptical system complexity
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent separates the control of different optical beams into independent control loops, allowing each beam to be adjusted separately using dedicated sensors and actuators. This segmentation enables independent optimization of each beam's alignment while maintaining overall system manageability through modular control architecture.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent employs universal control components such as galvanometer mirrors or deformable lenses that can control multiple optical beams simultaneously with a single actuator. This multi-functionality reduces the number of separate control mechanisms needed, thereby reducing device complexity while maintaining the ability to independently control each beam's position and shape.

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

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 system maintains precise alignment of optical beams, reducing power consumption and electro-mechanical complexity while ensuring high-performance target tracking and imaging.

Implementation Method 1

an optical device configured to spatially separate a first optical beam and a second optical beam

Methodology Applied
Scientific EffectRefraction: Refraction

Implementation Method 2

steering control provided by refractive elements and reflective mirrors

Methodology Applied
Scientific EffectReflection: Reflection

Implementation Method 3

divergence control provided by refractive elements

Methodology Applied
Scientific EffectRefraction: Refraction

Implementation Method 4

steering control provided by refractive elements and reflective mirrors

Methodology Applied
Scientific EffectReflection: Reflection

Data Source

PatentEP4603870A1Compact closed-loop bypass optical beam sensing and correction
Publication Date: 2025.08.20 RAYTHEON CO
  • EP4603870A1 patent drawingFigure 1
  • EP4603870A1 patent drawingFigure 2
  • EP4603870A1 patent drawingFigure 3

AI summary

An apparatus includes an optical device configured to spatially separate a first optical beam and a second optical beam. The apparatus also includes a divergence controller configured to adjust a divergence of the second optical beam and a steering controller configured to adjust a steering direction of the second optical beam. The apparatus further includes a far field sensor configured to receive a sample of the second optical beam after adjustment of the divergence and the steering direction of the second optical beam and generate measurements of the sample. In addition, the apparatus includes at least one controller configured to control the divergence controller and the steering controller based on the measurements of the sample.