Multi-Wavelength LED Inspection for Blister Seal Quality
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for inspecting the heat sealing quality of ophthalmic lens containers are inefficient and prone to human error, as they rely on manual inspection, single-wavelength illumination, or inadequate imaging techniques, leading to defective seals being shipped to customers due to insufficient detection of defects like air gaps and bubbles.
Innovation Solution
An automated inspection system using a camera directed at the top surface of the blister pack with a ring light capable of emitting multiple wavelengths of LED illumination, allowing for enhanced defect detection by capturing high-resolution images with different wavelengths to highlight various sealing defects.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If manual inspection methods are used to check sealing quality, then operational simplicity is maintained, but inspection accuracy and reliability deteriorate due to human error and inefficiency
Solution Approach 1:
The patent replaces manual mechanical inspection with an automated optical inspection system using a camera and multi-wavelength LED illumination. The system captures images under different wavelengths (blue, green, red) and uses image processing algorithms to automatically detect sealing defects, eliminating human error while maintaining operational simplicity through automation.
Solution Approach 2:
The patent introduces an intermediary image processing system that acts as a mediator between the physical sealing quality and the detection process. The system uses intermediate representations (images captured under different wavelengths) and algorithms to analyze sealing quality, providing a bridge between physical inspection and automated decision-making.
2Measurement precision
If single-wavelength illumination is used for imaging, then device complexity is reduced, but defect detection capability deteriorates due to insufficient contrast for different types of defects
Solution Approach 1:
The patent segments the illumination system into multiple independent wavelength components (blue LED, green LED, red LED). Each wavelength segment targets specific types of defects, allowing the system to detect various sealing issues (air gaps, bubbles, missing seals) by analyzing images from different wavelength segments separately and combining the results.
Solution Approach 2:
The patent applies local quality by using different wavelengths for different inspection purposes. Blue wavelength enhances detection of certain defect types, green for others, and red for yet another set. This localized optimization of illumination quality for specific detection needs maximizes defect visibility while managing system complexity.
3Productivity
If automated inspection systems are implemented, then productivity and inspection speed are improved, but implementation cost and system complexity increase
Solution Approach 1:
The patent creates a universal inspection system that can detect multiple types of sealing defects (air gaps, bubbles, missing seals, contaminants) using a single multi-wavelength illumination setup and camera system. This multi-functional approach increases productivity by inspecting all defect types simultaneously while managing complexity through a unified system architecture.
Solution Approach 2:
The patent merges multiple inspection functions into a single integrated system. The camera captures images under blue, green, and red LED illumination simultaneously or in sequence, and the processing system combines information from all wavelengths to make a unified sealing quality assessment, improving productivity while consolidating system complexity.
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 system significantly improves the accuracy and speed of sealing quality inspection, effectively identifying multiple defects such as air gaps, missing seals, and contaminants, ensuring only high-quality blister packs are delivered by providing enhanced contrast and reliable defect detection.
Implementation Method 1
ring light capable of emitting different wavelengths of illumination
Data Source
AI summary
An inspection system to inspect the consistency and thermal seal quality of blister packages, the system comprising an illumination module and a color imaging device suitably integrated with an optical module. The blister packages that are thermally sealed are sequentially presented to the color imaging device within its Field of View whereupon the inspection captures multiple images of the illuminated top side of the sealed blister package using the said image pickup devise. The images then undergo analysis to determine the gray scale values of the sealing area. By comparing the gray level values with predetermined gray level values that are programmed at setup, a decision is made to reject the inspected item if the analyzed gray level values is not substantially the same as the predetermined gray level values, or to accept the inspected item if the analyzed gray level values is substantially the same as the predetermined gray level values or rejecting the blister if determined otherwise.