Active Illumination 3D Zonal Imaging System Multipath Reduction

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional active illumination range cameras face challenges in achieving high intensity illumination and mitigating multipath light effects when imaging an entire field of view simultaneously, which affects the accuracy and quality of range images.

Innovation Solution

The camera partitions its field of view into sub-FOVs and synchronizes illumination and imaging systems to sequentially illuminate and image each zone, allowing for higher intensity illumination and reducing multipath light effects by controlling the illumination system to direct light only to specific zones and activating pixels only for those zones, thereby improving range image acquisition.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Illumination intensity

If the illumination system simultaneously illuminates the entire field of view, then the coverage area is maximized, but the illumination intensity is reduced and multipath light effects increase

Engineering Contradiction:
Improveillumination intensityVSAvoidfield of view coverage
Core Design Contradiction:
Illumination intensityVSArea of stationary object

Solution Approach 1:

The patent divides the field of view into multiple zones and sequentially illuminates each zone with the illumination system. This segmentation allows the illumination energy to be concentrated on smaller areas at any given time, thereby achieving high illumination intensity for each zone while maintaining comprehensive coverage of the entire field of view through sequential scanning.

Inventive Principle:
Principle #1Segmentation

2Speed

If the illumination system simultaneously illuminates the entire field of view, then the imaging speed is maximized, but multipath light interference increases

Engineering Contradiction:
Improveimaging speedVSAvoidmultipath light interference
Core Design Contradiction:
SpeedVSObject-affected harmful factors

Solution Approach 1:

The patent segments the field of view into multiple zones and sequentially illuminates and images each zone. This temporal and spatial segmentation ensures that only one zone is illuminated at a time, eliminating multipath light interference from other zones while maintaining acceptable imaging speed through the sequential process.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The illumination and imaging systems operate in periodic cycles, sequentially activating for different zones in a predetermined sequence. This periodic action allows the system to systematically cover the entire field of view while ensuring that each zone receives focused illumination without interference from other zones, thereby reducing multipath light effects.

Inventive Principle:
Principle #19Periodic action

3Productivity

If the camera images the entire field of view simultaneously, then the productivity is maximized, but the measurement precision deteriorates due to multipath light

Engineering Contradiction:
Improveimaging productivityVSAvoidrange image accuracy
Core Design Contradiction:
ProductivityVSMeasurement precision

Solution Approach 1:

The patent divides the field of view into multiple zones and sequentially images each zone. This segmentation approach improves measurement precision by eliminating multipath light interference that would otherwise degrade accuracy when imaging the entire field of view simultaneously. The sequential imaging process maintains productivity by systematically covering all zones in an efficient manner.

Inventive Principle:
Principle #1Segmentation

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 acquisition of range images with higher intensities of illumination and reduces multipath light interference, resulting in improved accuracy and quality of range images by focusing light and sensor activation on specific zones within the field of view.

Implementation Method 1

a photosensor having pixels on which the camera registers light that the features reflect from the transmitted light back to the camera

Methodology Applied
Scientific EffectLight reflection: Reflection

Implementation Method 2

The range camera processes reflected light from the features that pixels in the photosensor register to provide measures of distances to the features in the scene. In a time of flight (TOF) range camera the camera processes the registered reflected light from a feature to determine a round trip flight time of light from the camera to the feature and back to the camera.

Methodology Applied
Scientific EffectTime of flight: Time of Flight

Data Source

PatentEP3652562B1Active illumination 3D zonal imaging system
Publication Date: 2023.09.27 MICROSOFT TECHNOLOGY LICENSING LLC
  • EP3652562B1 patent drawingFigure 1A~1B
  • EP3652562B1 patent drawingFigure 1C~1D
  • EP3652562B1 patent drawingFigure 2A

AI summary

An active illumination range camera comprising illumination and imaging systems that is operable to provide a range image of a scene in the imaging system's field of view (FOV) by partitioning the range camera FOV into sub-FOVs, and controlling the illumination and imaging systems to sequentially illuminate and image portions of the scene located in the respective sub-FOVs.