Laser Edge Coating Removal via Optical Tracking

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing methods for controlling the edge width of photovoltaic devices are expensive and require significant downtime due to the need for precise positioning, and they lack the ability to efficiently direct a laser beam to ablate coatings at the edge of substrates effectively.

Innovation Solution

A system that uses an edge-tracking instrument to locate the edge of a photovoltaic device, adjusting both the substrate and laser source positions to create contiguous non-coated sections, employing a pulsed laser beam with near-infrared frequency and XYZ galvanometer-controlled mirrors for precise scribing, and includes gas pressure and vacuum positioners for accurate focusing and ablation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If traditional precision fixtures and XY positioning tables are used to control edge width, then positioning precision is improved, but device complexity and cost increase significantly

Engineering Contradiction:
Improveedge width control precisionVSAvoidpositioning system complexity
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

The patent replaces complex mechanical positioning systems (precision fixtures and XY positioning tables) with an optical tracking system. A sensor detects the substrate edge position, and a controller automatically adjusts the laser beam position based on detected deviations, substituting mechanical precision with optical-mechanical integration.

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

Solution Approach 2:

The system performs self-adjustment by detecting edge position deviations and automatically correcting the laser beam position. The sensor-controller-laser system continuously monitors and self-corrects positioning errors without requiring external intervention or complex pre-positioning fixtures.

Inventive Principle:
Principle #25Self-service

2Manufacturing precision

If traditional precision fixtures and XY positioning tables are used to control edge width, then positioning precision is improved, but production downtime increases due to maintenance requirements

Engineering Contradiction:
Improvepositioning precisionVSAvoiddowntime for maintenance
Core Design Contradiction:
Manufacturing precisionVSLoss of time

Solution Approach 1:

The patent eliminates complex mechanical positioning systems that require frequent calibration and maintenance. The optical sensor and controller system has fewer moving parts and requires minimal maintenance, significantly reducing production downtime while maintaining positioning precision.

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

Solution Approach 2:

The system continuously self-adjusts during operation without requiring shutdowns for recalibration. The real-time feedback loop allows the system to maintain precision throughout production runs, eliminating downtime associated with traditional mechanical system maintenance.

Inventive Principle:
Principle #25Self-service

3Ease of manufacture

If a fixed orientation laser beam at 0° angle of incidence is used, then laser alignment is simplified, but the ability to redirect the beam to track substrate edges is lost

Engineering Contradiction:
Improvelaser alignment simplicityVSAvoidlaser beam redirection capability
Core Design Contradiction:
Ease of manufactureVSAdaptability or versatility

Solution Approach 1:

The patent transforms the static, fixed-orientation laser system into a dynamic one. The laser beam orientation is continuously adjusted based on real-time edge position feedback, allowing the system to adapt to substrate variations while maintaining alignment through active control rather than fixed mechanical mounting.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The system uses sensor feedback to continuously monitor substrate edge position and automatically adjusts laser beam orientation accordingly. This closed-loop control allows the laser to track edges dynamically while maintaining precise alignment, combining the simplicity of fixed mounting with the versatility of active redirection.

Inventive Principle:
Principle #23Feedback

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

Enables efficient and precise removal of coatings from the edges of photovoltaic devices, reducing downtime and costs by maintaining precise positioning tolerances and ensuring consistent non-conductive edge widths, thereby maximizing device output.

Implementation Method 1

employing a pulsed laser beam with near-infrared frequency and XYZ galvanometer-controlled mirrors for precise scribing

Methodology Applied
Scientific EffectLaser ablation: Laser Ablation

Implementation Method 2

ablating a coating at a position corresponding to the located edge

Methodology Applied
Scientific EffectAblation: Ablation

Data Source

PatentEP2480342B1System and method for tracking and removing coating from an edge of a substrate
Publication Date: 2021.02.24 FIRST SOLAR INC
  • EP2480342B1 patent drawingFigure 1
  • EP2480342B1 patent drawingFigure 2
  • EP2480342B1 patent drawingFigure 3a~3b

AI summary

A method for removing coating from a substrate may include: locating an edge of a substrate; directing a laser beam along a first path to a first position on a surface of the substrate proximate to an edge of the substrate at an angle of incidence suitable to redirect the laser beam along a second path, through the substrate, to a second position on a second surface of the substrate corresponding to the located edge of the substrate, where the second surface can include a coating; and ablating at least a portion of coating at the second position on the second surface of the substrate.