3D Surface Measurement of Contoured Glass Using Pattern Reflection

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current methods for measuring the three-dimensional surface information of contoured glass sheets, particularly during manufacturing processes, are inefficient in providing accurate and rapid data acquisition and analysis of optical distortion and conformity to design specifications.

Innovation Solution

A system comprising a conveyor, displays projecting contrasting patterns, and cameras paired with each display to capture reflected images, which uses geometric and differential geometry equations to construct a three-dimensional mathematical description of the glass sheet surface, enabling analysis of optical characteristics and distortion measurement.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If multiple cameras are used to capture three-dimensional surface information, then measurement precision is improved, but device complexity increases

Engineering Contradiction:
Improvethree-dimensional surface information accuracyVSAvoidsystem complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The measurement system is segmented into multiple independent camera-display pairs, where each pair captures surface information from a specific viewing angle. This segmentation allows the system to achieve comprehensive three-dimensional measurement by combining data from multiple viewpoints, resolving the contradiction between measurement precision and device complexity through modular architecture

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

Each camera-display pair serves multiple functions: the display projects patterns onto the glass sheet surface while the camera captures the reflected patterns. This multi-functionality reduces the need for separate projection and detection devices, thereby improving measurement precision without proportionally increasing device complexity

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

2Productivity

If rapid data acquisition is implemented during conveyor transport, then productivity is improved, but measurement precision may deteriorate

Engineering Contradiction:
Improvedata acquisition speedVSAvoidsurface information accuracy
Core Design Contradiction:
ProductivityVSMeasurement precision

Solution Approach 1:

The system performs preliminary actions by projecting stable patterns onto the glass sheet surface before the glass moves through the measurement zone. The patterns are pre-positioned and maintained during conveyor transport, allowing rapid capture of accurate surface data without requiring the glass to be stationary, thus improving productivity while maintaining measurement precision

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The measurement system is designed to dynamically adapt to the moving glass sheet on the conveyor. Multiple cameras are positioned to capture images at different locations along the conveyor path, and the system processes these dynamic images to reconstruct accurate three-dimensional surface information, resolving the contradiction between rapid acquisition and precision

Inventive Principle:
Principle #15Dynamics

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 system allows for quick and accurate acquisition of three-dimensional surface data, enabling precise evaluation of glass sheet conformity and optical distortion, improving manufacturing efficiency and quality control.

Implementation Method 1

each camera detects the reflected image of the pattern projected on the surface of the glass sheet from its associated display

Methodology Applied
Scientific EffectReflection: Reflection

Data Source

PatentEP3314237B1System and method for developing three-dimensional surface information corresponding to a contoured glass sheet
Publication Date: 2021.11.03 GLASSTECH INC
  • EP3314237B1 patent drawingFigure 1~2
  • EP3314237B1 patent drawingFigure 3~4
  • EP3314237B1 patent drawingFigure 5~6

AI summary

A system for acquiring surface data from one of the surfaces of a curved glass sheet and developing a surface definition of the glass sheet includes a conveyor for conveying the glass sheet in a first direction, at least one display projecting a preselected multi-phase non-repeating contrasting pattern, and at least one camera, each one of the cameras uniquely paired with one of the displays. The system may also include a control programmed to execute logic for controlling each of the camera/display pairs to acquire the desired images, and logic for analyzing and combining the data acquired by the cameras to construct a definition of the surface of the glass sheet.