Optical Condition Determination for Appearance Inspection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing optical condition determination methods for appearance inspection often deviate between simulation and actual measurement, making it difficult to derive the optimum optical conditions for effective defect detection.
Innovation Solution
An optical condition determination system that performs optical simulations on surface texture and defect models under various conditions, synthesizes images, calculates evaluation values for defect detectability, and analyzes correlations to find suitable optical conditions for appearance inspection.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of time
If optical simulation is used to determine optical conditions, then the determination process can be performed in advance, but the simulation results may deviate from actual measurements making it difficult to derive optimum conditions
Solution Approach 1:
The system performs optical simulations under multiple different optical conditions (varying illumination angles, wavelengths, polarizations, etc.) and selects the condition that yields the highest evaluation value. By changing simulation parameters systematically and comparing results across conditions, the system derives optimum conditions that better align with actual measurements while maintaining efficient pre-determination.
Solution Approach 2:
The system creates synthetic images that replicate actual inspection images by combining simulated surface texture images with simulated defect images. These synthetic images serve as virtual copies that can be evaluated without requiring actual physical measurements, allowing optimization of optical conditions through simulation while maintaining fidelity to real-world inspection scenarios.
2Measurement precision
If multiple optical conditions are simulated to find the optimum, then defect detection accuracy improves, but the computational complexity and processing time increase
Solution Approach 1:
The optical simulation process is divided into separate modules: surface texture simulation, defect simulation, image synthesis, and evaluation. Each module handles a specific aspect of the simulation independently, allowing for optimized computation of each component and facilitating parallel processing to reduce overall complexity while maintaining comprehensive multi-condition analysis.
Solution Approach 2:
The system pre-calculates and stores simulation results for various optical conditions in databases before actual inspection occurs. Surface texture images and defect images are simulated in advance under multiple conditions, and these pre-computed results are readily available for rapid comparison and selection during the inspection process, reducing real-time computational burden.
Data Source
AI summary
An optical condition determination system includes a simulation execution unit that performs an optical simulation on a surface texture model that models a surface texture of a target object of the appearance inspection, and a defect model that models a defect of the target object, under a plurality of optical conditions to generate a surface texture image and a defect image, an image synthesizing unit that synthesizes the surface texture image and the defect image generated by an optical simulation under the same optical condition to generate a synthetic image, an evaluation value calculating unit that calculates an evaluation value representing easiness of detecting the defect in the synthetic image, a correlation analysis unit that analyzes a correlation between an optical condition and the evaluation value corresponding to the synthetic image, and an optimum condition searching unit that searches for the optical condition suitable for the appearance inspection based on an analysis result of the correlation.