Laminated Glass Touch Switching for Intuitive Optical Control

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Solution Overview

Problem

Existing composite windscreens with integrated optoelectronic functional elements face challenges in intuitive operation and require adjustments to other vehicle components due to non-intuitive placement of actuating devices, complicating the integration of varying designs and configurations.

Innovation Solution

A composite windscreen design with an optoelectronic functional element embedded between two panes, featuring a capacitive touch switching element integrated directly into the laminated glass pane, allowing for intuitive operation and eliminating the need for separate components by using a laminated film with pre-integrated touch switching capabilities.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Use of energy by moving object

If electrochromic devices are integrated into building windows to control light and heat, then energy efficiency and comfort are improved, but the devices are bulky, expensive, and lack design flexibility

Engineering Contradiction:
Improveenergy efficiencyVSAvoiddevice complexity
Core Design Contradiction:
Use of energy by moving objectVSDevice complexity

Solution Approach 1:

The patent replaces the mechanical/electrical system of traditional electrochromic devices with a magnetic field-based system. Magnetic field-responsive particles suspended in the interlayer change their orientation or aggregation state in response to applied magnetic fields, controlling light transmission without requiring complex electrical circuits, power supplies, or control electronics embedded in the window glass.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent utilizes changes in magnetic field parameters (strength, direction, frequency) to control the optical properties of the window. By varying the magnetic field applied to the interlayer, the window can transition between different states of light transmission, providing dynamic control similar to electrochromic devices but through a simpler magnetic actuation mechanism.

Inventive Principle:
Principle #35Parameter changes

2Temperature

If traditional electrochromic devices are used to control solar heat gain, then thermal comfort is improved, but the cost of the window assembly increases significantly

Engineering Contradiction:
Improvethermal comfortVSAvoidmanufacturing cost
Core Design Contradiction:
TemperatureVSEase of manufacture

Solution Approach 1:

The patent employs relatively inexpensive magnetic field-responsive particles and standard glass laminating materials instead of costly electrochromic coatings or integrated electrical systems. The magnetic particles can be incorporated into the interlayer during standard lamination processes, avoiding the need for specialized manufacturing equipment or expensive materials, thereby reducing overall window assembly cost while maintaining thermal control functionality.

Inventive Principle:
Principle #27Cheap short-living objects (Disposable)

Solution Approach 2:

The patent introduces a magnetic field as an intermediary between the control system and the window glass. Rather than directly embedding electrical components in the glass, a magnetic field is applied to the interlayer containing magnetic particles, which then mediate the control of light and heat transmission. This intermediary approach simplifies the overall system and reduces manufacturing complexity and cost.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Ease of operation

If electrochromic glass is installed to provide dynamic light control, then occupant comfort is improved, but the design flexibility and aesthetic options are reduced

Engineering Contradiction:
Improvelight controlVSAvoiddesign flexibility
Core Design Contradiction:
Ease of operationVSShape

Solution Approach 1:

The patent allows for segmentation of the magnetic field control system, where different zones of the window can be independently controlled by applying magnetic fields to specific regions of the interlayer. This enables dynamic control of light transmission in different areas while maintaining standard window manufacturing processes and aesthetic appearances when the magnetic particles are properly formulated and distributed.

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

Facilitates intuitive operation of the functional element and simplifies manufacturing by integrating the touch switching element within the laminated glass pane, reducing the need for additional components and adjustments to other vehicle parts.

Implementation Method 1

a magnetic field-responsive interlayer positioned between the first pane and the second pane. The magnetic field-responsive interlayer includes a plurality of magnetic field-responsive particles distributed throughout the interlayer

Methodology Applied
Scientific EffectMagnetic field-responsive behavior: Magnetism

Implementation Method 2

a transparent adhesive layer positioned between the second pane and the magnetic field-responsive interlayer

Methodology Applied
Scientific EffectAdhesion: Adhesive

Data Source

PatentEP4031366B1Laminated glass with electrically driven optical properties
Publication Date: 2026.05.06 SAINT GOBAIN SEKURIT FRANCE
  • EP4031366B1 patent drawingFigure 1~2
  • EP4031366B1 patent drawingFigure 3~4
  • EP4031366B1 patent drawingFigure 5a~5b

AI summary

The invention relates to a composite pane having electrically controllable optical properties and comprising an outer pane (1) and an inner pane (2), which are connected to one another by means of a thermoplastic intermediate layer (3), an optoelectronic functional element (4; S) having electrically controllable optical properties being embedded in the intermediate layer (3). Said functional element has an active layer (5), between a first carrier film (6) and a second carrier film (7), whose two faces are associated with transparent flat control electrodes (8, 9). A capacitative contact switch element (T; 11) is located between the active layer (5) and the thermoplastic intermediate layer (3), preferably in direct contact with the second carrier film (7) facing in the direction of the inner pane (2).