Lidar Beam Splitting for Extended Range Detection

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional laser detection and ranging systems have limited effective range due to output power constraints of their laser light sources and the need for a wide field-of-view, which restricts their ability to measure target characteristics over long distances efficiently.

Innovation Solution

The system employs a beam forming element that splits the light beam into multiple non-contiguous beamlets, concentrating light intensity on specific areas of the target, allowing for enhanced measurement of target characteristics over longer distances without illuminating the entire field-of-view, thereby increasing operational efficiency and range.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Area of stationary object

If the laser beam is transmitted over a wide field-of-view to cover large areas, then the coverage area is improved, but the light intensity per unit area decreases, limiting the effective range

Engineering Contradiction:
Improvefield-of-view coverage areaVSAvoidlight intensity on target
Core Design Contradiction:
Area of stationary objectVSIllumination intensity

Solution Approach 1:

The patent divides the laser beam into multiple discrete beamlets using a beam forming element (such as a holographic element or diffractive optical element). Each beamlet is directed toward a different spatial location within the field-of-view, allowing the system to cover a wide area while maintaining high light intensity at each individual beamlet location. This segmentation resolves the contradiction by enabling both wide coverage and concentrated intensity through spatial distribution of multiple beamlets.

Inventive Principle:
Principle #1Segmentation

2Length of stationary object

If the laser output power is increased to extend the effective range, then the measurement distance is improved, but the energy consumption and system complexity increase

Engineering Contradiction:
Improveeffective rangeVSAvoidlaser energy consumption
Core Design Contradiction:
Length of stationary objectVSUse of energy by moving object

Solution Approach 1:

The patent applies local quality by concentrating the laser energy into multiple focused beamlets rather than distributing it uniformly. Each beamlet delivers high local intensity to specific points on the target, enabling long-range detection without requiring excessive total power. The beam forming element creates regions of high intensity (at beamlet locations) against a dark background, achieving extended range while maintaining energy efficiency through localized energy concentration.

Inventive Principle:
Principle #3Local quality

3Illumination intensity

If the laser beam is concentrated into a single beam to maximize intensity, then the light intensity on target is improved, but the field-of-view coverage is reduced

Engineering Contradiction:
Improvelight intensity on targetVSAvoidfield-of-view coverage
Core Design Contradiction:
Illumination intensityVSArea of stationary object

Solution Approach 1:

The patent transitions from a single-dimensional beam to a multi-dimensional beamlet structure. The beam forming element spatially distributes the laser energy across multiple dimensions, creating an array of beamlets that cover a two-dimensional field-of-view. Each beamlet maintains the intensity characteristics of a concentrated beam, while the collective array provides wide area coverage, effectively adding spatial dimensionality to resolve the contradiction between intensity and coverage.

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

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 laser detection and ranging systems to achieve a significantly increased effective range, from approximately two kilometers to over ten kilometers, while maintaining energy efficiency and operational effectiveness with limited laser light sources.

Implementation Method 1

The system employs a beam forming element that splits the light beam into multiple non-contiguous beamlets, concentrating light intensity on specific areas of the target

Methodology Applied
Scientific EffectLight beam splitting and concentration: Diffraction

Implementation Method 2

Lasers used to generate the light beam produce a coherent beam of monochromatic light

Methodology Applied
Scientific EffectLaser coherent light generation: Laser

Implementation Method 3

receiving the transmitted light energy reflected from the object

Methodology Applied
Scientific EffectLight reflection and backscattering: Reflection

Data Source

PatentEP2389599B1Energy efficient laser detection and ranging system
Publication Date: 2015.09.16 RAYTHEON CO
  • EP2389599B1 patent drawingFigure 1
  • EP2389599B1 patent drawingFigure 2~3
  • EP2389599B1 patent drawingFigure 4

AI summary

According to one embodiment, a laser detection and ranging system includes a beam forming element that is optically coupled to a light source. The light source generates a light beam that is split by the beam forming element into multiple beamlets and directed toward a target. At least one of the beamlets are reflected from the target as backscattered light that is received by a detector that generates a signal indicative of a characteristic of the target.