Segmented Smart Glazing Control to Prevent Switching Crosstalk

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Glazing units with electrically controllable optical properties face issues with 'cross talk' due to potential shifts in the reference potential of the second surface electrode, causing unintended switching of non-activated areas, especially when multiple switching areas are activated, leading to reduced precision and unwanted optical changes.

Innovation Solution

Implementing a control unit that applies phase-shifted alternating voltages between electrode segments of the first surface electrode and the second surface electrode, using software or hardware components to manage these voltages, which compensates for potential shifts and reduces cross talk by creating opposing currents.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If multiple switching areas are activated simultaneously, then the functional element can provide diverse optical properties in different areas, but ground shift causes crosstalk between areas leading to unintended switching

Engineering Contradiction:
Improveoptical property control in multiple areasVSAvoidswitching precision
Core Design Contradiction:
Adaptability or versatilityVSReliability

Solution Approach 1:

The second surface electrode is divided into multiple electrode segments corresponding to each switching area, with insulating lines separating them. This segmentation isolates the electrical circuits of different switching areas, preventing ground shift from causing crosstalk between areas while allowing each area to be controlled independently with high precision

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

Insulating lines are introduced as intermediary elements between adjacent electrode segments. These insulating lines act as electrical barriers that prevent potential shifts in one area from affecting neighboring areas, thereby eliminating crosstalk while maintaining the ability to control multiple areas simultaneously

Inventive Principle:
Principle #24Intermediary (Mediator)

2Reliability

If the second surface electrode is segmented with insulating lines, then crosstalk is eliminated, but the number of insulating lines increases making the composite disk less aesthetic

Engineering Contradiction:
Improveswitching precisionVSAvoidaesthetic appearance
Core Design Contradiction:
ReliabilityVSShape

Solution Approach 1:

Instead of segmenting the first surface electrode (which would require insulating lines on the visible side), the patent segments the second surface electrode. This approach achieves the same electrical isolation function while keeping the first surface electrode continuous and aesthetically pleasing from the viewer's perspective

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent inverts the conventional approach by segmenting the second surface electrode rather than the first surface electrode. This inversion allows the insulating lines to be positioned on the non-visible side of the composite disk, eliminating their visual impact while maintaining their electrical isolation function

Inventive Principle:
Principle #13The other way round (Inversion)

3Illumination intensity

If ITO layers are used as surface electrodes for transparency, then visibility through the composite disk is maintained, but the electrical resistance is comparatively high causing ground shift

Engineering Contradiction:
Improvelight transmissionVSAvoidelectrical conductivity
Core Design Contradiction:
Illumination intensityVSReliability

Solution Approach 1:

By segmenting the second surface electrode into separate electrode segments, the patent creates isolated electrical circuits for each switching area. This segmentation prevents ground shift caused by the high resistance of ITO layers, as potential shifts in one area no longer affect other areas through the continuous electrode structure

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent applies different electrical configurations to different areas: each electrode segment is independently connected to the control unit, allowing optimized voltage application to each switching area. This local quality approach compensates for the high resistance of ITO by providing dedicated electrical pathways for each area

Inventive Principle:
Principle #3Local quality

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 prevents or reduces unwanted switching of non-activated areas, improving the precision of optical changes and maintaining desired switching states, even with multiple activated areas, by compensating for potential shifts through phase-shifted voltage application.

Implementation Method 1

The control unit (10) is designed and arranged to apply an alternating voltage between at least two electrode segments (8.1, 8.2) of the first surface electrode (8) and the second surface electrode (9), wherein the alternating voltages are phase-shifted (have a phase shift relative to one another)

Methodology Applied
Scientific EffectPhase-shifted alternating voltage: Alternating Magnetic Field

Implementation Method 2

electrochromic functional elements are known, for example from US 20120026573 A1, WO 2010147494 A1 and EP 1862849 A1 and WO 2012007334 A1, in which a change in transmission occurs through electrochemical processes induced by the applied electrical voltage

Methodology Applied
Scientific EffectElectrochromism: Electrochromism

Implementation Method 3

The active layer contains liquid crystals embedded in a polymer matrix. When no voltage is applied, the liquid crystals are randomly oriented, resulting in strong scattering of the light passing through the active layer. When a voltage is applied to the surface electrodes, the liquid crystals align in a common direction, and the transmission of light through the active layer is increased

Methodology Applied
Scientific EffectLiquid crystal alignment: Liquid Crystals

Implementation Method 4

SPD functional elements (suspended particle device), which are known, for example, from EP 0876608 B1 and WO 2011033313 A1. The transmission of visible light through SPD functional elements can be controlled by the applied voltage

Methodology Applied
Scientific EffectSuspended particle device: Electrophoresis

Data Source

PatentEP4341088B1Glazing unit with electrically controllable optical properties with multiple independent switching areas
Publication Date: 2024.11.20 SAINT GOBAIN SEKURIT FRANCE
  • EP4341088B1 patent drawingFigure 1~2
  • EP4341088B1 patent drawingFigure 3~4
  • EP4341088B1 patent drawingFigure 5~6

AI summary

The invention relates to a glazing unit with electrically controllable optical properties, comprising a plurality of independent switching regions (S1, S2, S3, S4). The glazing unit comprises a composite pane with an electrically controllable functional element (4) and a control unit (10) which is suitable for controlling the optical properties of the functional element (4). The functional element (4) has an active layer (5) with electrically controllable optical properties between a first flat electrode (8) and a second flat electrode (9). The first flat electrode (8) is divided into at least two separate electrode segments (8.1, 8.2, 8.3, 8.4) by at least one insulating line (8'), and an electric voltage can be applied between each electrode segment (8.1, 8.2, 8.3, 8.4) of the first flat electrode (8) and the second flat electrode (9) independently of one another in order to control the optical properties of the active layer (5) section located therebetween. According to the invention, the control unit (10) is suitable for applying a respective alternating voltage between at least two electrode segments (8.1, 8.2, 8.3, 8.4) of the first flat electrode (8) and the second flat electrode (9), wherein the alternating voltages are phase-shifted.