Watch Photovoltaic Cell Electrode Layout for Aesthetic Light Collection

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Photovoltaic cells in watch faces suffer from reduced efficiency due to hidden electrodes, which induce electrical resistance and block light radiation, compromising their performance, especially in bright sunlight, while existing solutions like translucent dials or hidden electrodes detract from aesthetics.

Innovation Solution

A watch case component with a photovoltaic cell featuring an upper electrode arranged in a visible pattern, such as a constellation, connected to a peripheral portion to collect light and improve efficiency without affecting aesthetics.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Shape

If the upper electrode is hidden on the photovoltaic cell to improve aesthetics, then the visual appearance is improved, but the electrical resistance increases and efficiency decreases

Engineering Contradiction:
Improveaesthetic appearanceVSAvoidelectrical efficiency
Core Design Contradiction:
ShapeVSReliability

Solution Approach 1:

The upper electrode is divided into multiple segments arranged in a constellation pattern rather than a continuous grid. This segmentation allows the electrode to be visually appealing while maintaining electrical conductivity through the connected segments, resolving the contradiction between aesthetics and efficiency.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

Different regions of the upper electrode are optimized differently: the peripheral portion is continuous to maximize light collection, while the inner segments are arranged in a constellation pattern for aesthetic purposes. This local differentiation allows both aesthetic and efficiency requirements to be met simultaneously.

Inventive Principle:
Principle #3Local quality

2Shape

If a translucent dial is used to hide the electrode, then the aesthetic appearance is improved, but light radiation is blocked and efficiency decreases

Engineering Contradiction:
Improveaesthetic appearanceVSAvoidlight absorption efficiency
Core Design Contradiction:
ShapeVSUse of energy by moving object

Solution Approach 1:

The electrode design is extracted from the traditional grid pattern and reconfigured as a constellation pattern with a peripheral portion. This extraction allows the electrode to be visible and aesthetically pleasing while maintaining its light-collection function, eliminating the need for a translucent dial that would block light.

Inventive Principle:
Principle #2Taking out (Extraction)

3Shape

If the upper electrode is arranged in a visible pattern to improve aesthetics, then the visual appearance is improved, but the electrode complexity increases

Engineering Contradiction:
Improveaesthetic appearanceVSAvoidelectrode structure complexity
Core Design Contradiction:
ShapeVSDevice complexity

Solution Approach 1:

The upper electrode structure serves multiple functions simultaneously: it collects charge carriers electrically, provides a visible constellation pattern for aesthetics, and maintains a peripheral portion for light collection. This multi-functionality reduces the need for separate components, actually simplifying the overall device while achieving aesthetic goals.

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

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

The visible electrode pattern enhances charge carrier collection and reduces resistance, improving photovoltaic cell efficiency while maintaining aesthetic appeal.

Implementation Method 1

a photovoltaic cell (20) having an elementary solar cell (21) interposed between two electrodes

Methodology Applied
Scientific EffectPhotovoltaic effect: Photovoltaic Effect

Implementation Method 2

The top electrode is positioned on the side of the photovoltaic cell exposed to incident light and its function is to collect the charge carriers generated by the elementary solar cell

Methodology Applied
Scientific EffectElectrical conduction: Conduction (electrical)

Data Source

PatentEP4280000B1Trim component for a watch comprising a photovoltaic cell and watch comprising said trim component
Publication Date: 2026.02.18 THE SWATCH GRP RES & DEVELONMENT LTD
  • EP4280000B1 patent drawingFigure 1~3

AI summary

The invention relates to a watch case component (10) comprising a photovoltaic cell (20) having an elementary solar cell (21) interposed between two electrodes, one of which, called the "upper electrode" (22), is arranged on a face of the elementary solar cell (21) intended to be subjected to incident light radiation, said upper electrode (22) being formed by segments (220) arranged according to a predetermined pattern conforming to a graphic representation of a constellation, the photovoltaic cell (20) being intended to be electrically connected to an electronic watch movement (30).