3D Mirror Reconstruction via Polarization Field Triangulation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing methods for reconstructing mirror surfaces are inadequate due to their 'invisible' nature, as they rely on insufficient ray path information and require additional geometry constraints, making it difficult to accurately recover 3-D geometry, especially for complex shapes.

Innovation Solution

A system and method utilizing a polarization field generated by a commercial LCD without a top polarizer, where each outgoing ray has a unique polarization state, allowing for the decoding of incident rays and their directions, enabling accurate 3-D reconstruction of mirror surfaces through ray-ray triangulation and Poisson integration.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If multiple viewpoints or moving illuminant are used to determine ray direction, then measurement precision is improved, but device complexity increases

Engineering Contradiction:
Improveray path determination accuracyVSAvoidsystem complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent changes the polarization state parameter of the light source to encode ray direction information. By using a polarization field with unique polarization states for different ray directions, the system determines ray paths without requiring multiple viewpoints or moving illuminants, thus improving measurement precision while avoiding increased device complexity

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent introduces polarization state as an intermediary carrier to encode ray direction information. The polarization field acts as a mediator between the light source and the mirror surface, allowing the system to extract directional information from the reflected light's polarization properties without complex mechanical setups

Inventive Principle:
Principle #24Intermediary (Mediator)

2Device complexity

If additional geometry constraints are assumed, then device complexity is reduced, but manufacturing precision deteriorates

Engineering Contradiction:
Improvesystem complexityVSAvoidsurface reconstruction accuracy
Core Design Contradiction:
Device complexityVSManufacturing precision

Solution Approach 1:

The patent uses polarization state as an additional parameter to encode surface geometry information. By analyzing the polarization changes of reflected light, the system can reconstruct mirror surfaces with high precision without needing to assume geometric constraints like planarity or smoothness, thus maintaining manufacturing precision while keeping device complexity low

Inventive Principle:
Principle #35Parameter changes

3Measurement precision

If coded patterns are laid out on the mirror surface, then measurement precision is improved, but ease of operation deteriorates

Engineering Contradiction:
Improvesurface reconstruction accuracyVSAvoidoperation simplicity
Core Design Contradiction:
Measurement precisionVSEase of operation

Solution Approach 1:

The patent uses the polarization field as an intermediary to encode measurement information in the light itself, rather than requiring physical patterns to be applied to the mirror surface. The polarization state of the reflected light carries the necessary information for precise surface reconstruction, eliminating the need for manual pattern application and improving ease of operation

Inventive Principle:
Principle #24Intermediary (Mediator)

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 effectively reconstructs complex mirror surfaces with high fidelity, eliminating the need for rotating polarizers and additional constraints, and is validated through both simulated and real-world experiments with accurate surface normal maps and 3-D surface recovery.

Implementation Method 1

A light source generates light that is received by a polarization field generator of the system. The polarization field generator generates a polarization field that illuminates the target object being imaged such that each outgoing ray has a unique polarization state.

Methodology Applied
Scientific EffectPolarization field generation: Polarisation

Implementation Method 2

A camera of the system captures images of the illuminated target object

Methodology Applied
Scientific EffectLight reflection: Reflection

Implementation Method 3

The captured images are received by a processor of the system that: (1) performs a polarization field decoding algorithm that decodes the polarization field to obtain a set of incident rays

Methodology Applied
Scientific EffectPolarization decoding: Polarisation

Implementation Method 4

performs a ray-ray triangulation to determine a set of 3-D intersection points

Methodology Applied
Scientific EffectTriangulation:

Implementation Method 5

performs a 3-D reconstruction algorithm that uses the set of incident rays, the set of camera rays and the intersection points to reconstruct a 3-D surface

Methodology Applied
Scientific EffectPoisson integration:

Data Source

PatentUS12149673B2System and method for reconstructing 3-D shapes of objects from reflection image
Publication Date: 2024.11.19 BOARD OF SUPERVISORS OF LOUISIANA STATE UNIV & AGRI & MECHANICAL COLLEGE
  • US12149673B2 patent drawing
  • US12149673B2 patent drawing
  • US12149673B2 patent drawing

AI summary

A system and method are provided for reconstructing 3-D point cloud. A light source generates light that is received by a polarization field generator, which generates a polarization field that illuminates the target object being imaged such that each outgoing ray has a unique polarization state. A camera captures images of the illuminated target object and the captured images are received by a processor that: (1) performs a polarization field decoding algorithm that decodes the polarization field to obtain a set of incident rays; (2) performs a camera ray decoding algorithm to obtain a set of camera rays; (3) performs a ray-ray intersection algorithm that determines intersection points where the incident rays and the camera rays intersect; and (4) performs a 3-D reconstruction algorithm that uses the set of incident rays, the set of camera rays and the intersection points to reconstruct a 3-D point cloud of the target object.