Electrochromic Pane Cutting Around Defects for Higher Yield

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Electrochromic windows face challenges in realizing their full commercial potential due to issues such as defects and low quality, which reduce yield and effectiveness, despite advancements in electrochromic technology.

Innovation Solution

A method of manufacturing electrochromic windows where a cutting pattern is defined after characterizing the electrochromic device for defects and quality, allowing for exclusion of defective areas and strategic cutting to maximize usable glass sheet area, incorporating techniques like laser scribing, bus bar application, and laminating for strength, to produce high-quality and efficient electrochromic panes.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If electrochromic devices are fabricated on glass sheets and cut into panes using conventional methods, then manufacturing process is simple, but defects reduce yield and quality

Engineering Contradiction:
ImproveyieldVSAvoidquality
Core Design Contradiction:
ProductivityVSReliability

Solution Approach 1:

The patent applies preliminary action by characterizing the electrochromic device for defects and quality issues before defining the cutting pattern. This allows defective areas to be identified and excluded in advance, ensuring that only high-quality regions are used for manufacturing panes, thereby improving both yield and quality simultaneously

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent implements local quality by creating cutting patterns that are specifically tailored to the quality characteristics of different regions on the glass sheet. Each cutting pattern is customized to exclude defective areas while maximizing the use of high-quality regions, ensuring that each pane is made from the best available material

Inventive Principle:
Principle #3Local quality

2Reliability

If cutting pattern is defined before fabrication, then manufacturing process is efficient, but defects cannot be excluded leading to lower quality

Engineering Contradiction:
ImprovequalityVSAvoidyield
Core Design Contradiction:
ReliabilityVSProductivity

Solution Approach 1:

The patent reverses the conventional sequence by performing the characterization action before the cutting pattern definition. This preliminary characterization identifies defective areas, allowing the cutting pattern to be designed to exclude them, thus prioritizing quality without significantly compromising productivity

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent changes the temporal parameter of when quality assessment occurs in the manufacturing process. By shifting the characterization step to occur before cutting pattern definition rather than after, the process enables quality-based sorting and optimization of cutting patterns

Inventive Principle:
Principle #35Parameter changes

3Ease of manufacture

If high leakage current or high TCO resistivity is present, then manufacturing cost is reduced, but pane size must be limited reducing productivity

Engineering Contradiction:
Improvemanufacturing costVSAvoidpane size
Core Design Contradiction:
Ease of manufactureVSProductivity

Solution Approach 1:

The patent applies local quality by creating customized cutting patterns that adapt to the specific electrical characteristics of the electrochromic device. When high leakage current or high TCO resistivity is detected, the cutting pattern is modified to limit pane sizes to ensure adequate performance, while still utilizing the maximum possible area of the glass sheet

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The patent changes the pane size parameter dynamically based on the measured electrical characteristics of the device. The cutting pattern generation process adjusts pane dimensions according to leakage current and TCO resistivity levels, optimizing the balance between performance requirements and material utilization

Inventive Principle:
Principle #35Parameter changes

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 improves the yield and quality of electrochromic windows by effectively excluding defects and optimizing pane sizes and shapes, leading to more efficient and reliable electrochromic devices with enhanced performance and reduced rejection rates.

Implementation Method 1

Electrochromism is a phenomenon in which a material exhibits a reversible electrochemically-mediated change in an optical property when placed in a different electronic state, typically by being subjected to a voltage change. One well known electrochromic material is tungsten oxide (WO3). Tungsten oxide is a cathodic electrochromic material in which a coloration transition, transparent to blue, occurs by electrochemical reduction.

Methodology Applied
Scientific EffectElectrochromism: Electrochromism

Implementation Method 2

Defective areas throughout the electrochromic device may be removed or mitigated by, for example, localized laser heating.

Methodology Applied
Scientific EffectLaser heating: Laser

Data Source

PatentEP3876030A1Electrochromic window fabrication method
Publication Date: 2021.09.08 VIEW INC
  • EP3876030A1 patent drawingFigure 1A
  • EP3876030A1 patent drawingFigure 1B
  • EP3876030A1 patent drawingFigure 2A

AI summary

Methods of manufacturing electrochromic windows are described. An electrochromic device is fabricated to substantially cover a glass sheet, for example float glass, and a cutting pattern is defined based on one or more low-defectivity areas in the device from which one or more electrochromic panes are cut. Laser scribes and/or bus bars may be added prior to cutting the panes or after. Edge deletion can also be performed prior to or after cutting the electrochromic panes from the glass sheet. Insulated glass units (IGUs) are fabricated from the electrochromic panes and optionally one or more of the panes of the IGU are strengthened.