Light Dimming Module Uniform Transmittance via Composite Electrodes

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Solution Overview

Problem

Large-area light control sheets with transparent conductive films face issues with nonuniform transmittance due to voltage drop, requiring high drive voltages and increasing power consumption, making them difficult to power with solar batteries and limiting their mobility and uniformity.

Innovation Solution

The light control module incorporates a light control sheet with a liquid crystal layer between transparent electrodes, where the electrodes are supplemented with lower resistance copper wires and copper oxynitride layers to minimize voltage gradients, ensuring uniform transmittance across the sheet.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If transparent conductive film electrodes are used in large-area light control sheets, then the sheet can be driven, but wire resistance becomes high and voltage gradient occurs causing nonuniform transmittance

Engineering Contradiction:
Improveuniformity of transmittanceVSAvoidpower consumption
Core Design Contradiction:
ReliabilityVSUse of energy by moving object

Solution Approach 1:

The patent combines transparent conductive films with copper wires and copper oxynitride layers to create a composite electrode structure. This composite approach leverages the transparency of the film and the low resistance of copper to achieve both uniform transmittance and reduced power consumption.

Inventive Principle:
Principle #40Composite materials

Solution Approach 2:

The patent applies different materials with different electrical properties to different regions of the electrode structure. Copper wires with high conductivity are embedded in specific patterns throughout the transparent conductive film, creating local quality variations that optimize both electrical performance and optical properties.

Inventive Principle:
Principle #3Local quality

2Reliability

If higher drive voltage is applied to reduce nonuniformity in transmittance, then uniformity improves, but power consumption increases

Engineering Contradiction:
Improveuniformity of transmittanceVSAvoiddrive power
Core Design Contradiction:
ReliabilityVSPower

Solution Approach 1:

The patent changes the electrical parameters of the electrode system by introducing low-resistance copper pathways. This fundamentally alters the voltage distribution characteristics, allowing uniform transmittance to be achieved at lower drive voltages through improved electrical conductivity rather than increased voltage.

Inventive Principle:
Principle #35Parameter changes

3Reliability

If thickness of the electrode is increased to reduce wire resistance, then resistance decreases, but transmittance of the light control sheet is reduced

Engineering Contradiction:
Improveelectrical conductivityVSAvoidlight transmittance
Core Design Contradiction:
ReliabilityVSIllumination intensity

Solution Approach 1:

The patent creates a composite electrode system where thin transparent conductive films are combined with embedded copper wires. This composite structure achieves the electrical conductivity of thick electrodes while maintaining the optical transparency of thin films, as the copper wires are positioned to minimize light blocking.

Inventive Principle:
Principle #40Composite materials

Solution Approach 2:

The copper wires are strategically positioned in specific patterns within the electrode structure, creating local high-conductivity pathways without uniformly increasing electrode thickness. This localized approach maintains overall transmittance while providing sufficient conductivity.

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 configuration allows for a low-voltage operation of the light control module, maintaining uniform transmittance and reducing power consumption, enabling the module to be driven by solar power and used in movable applications without the need for extensive wiring.

Implementation Method 1

the light control sheet is configured to include a liquid crystal layer held between electrodes and be switchable between an opaque state in which incident light is dispersed and a transparent state in which incident light is transmitted, by changing orientation of liquid crystal molecules contained in the liquid crystal layer according to a voltage applied to the electrodes

Methodology Applied
Scientific EffectLiquid crystal orientation change: Liquid Crystals

Implementation Method 2

the electrodes are supplemented with lower resistance copper wires and copper oxynitride layers to minimize voltage gradients

Methodology Applied
Scientific EffectElectrical conduction: Conduction (electrical)

Data Source

PatentEP3444656B1Light dimming module
Publication Date: 2022.10.26 TOPPAN HOLDINGS INC
  • EP3444656B1 patent drawingFigure 1~2
  • EP3444656B1 patent drawingFigure 3~4
  • EP3444656B1 patent drawingFigure 5~6

AI summary

The present embodiment provides a light control module driven at a low voltage, and a light control module MDL of the present embodiment includes: a light control sheet 30 including a light control layer LQ switchable between transparent and opaque states according to an applied voltage, a first electrode 34 made of a transparent conductive material, and a second electrode 36 facing the first electrode 34 with the light control layer LQ therebetween and made of a transparent conductive material; and a drive circuit DRV applying a drive voltage to the first and second electrodes 34 and 36, wherein when a maximum transmittance of the light control layer LQ is equivalent to a Munsell value of 100%, and a voltage is applied so that a transmittance equivalent to a Munsell value of 90% is obtained in a region closest to a feeding area PIN, a transmittance higher than a transmittance equivalent to a Munsell value of 50% is obtained in a region farthest from the feeding area PIN.