Automated surface inspection of small customer-specific optical elements
| Autor: | Patric Perez, Carsten Ziolek, Sabine Linz-Dittrich, Carlo Bach, Alexander Schöch |
|---|---|
| Rok vydání: | 2017 |
| Předmět: |
Surface (mathematics)
Automated optical inspection Engineering drawing Computer science business.industry 010401 analytical chemistry ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION 01 natural sciences 0104 chemical sciences 010309 optics Automated X-ray inspection 0103 physical sciences Computer vision Artificial intelligence Electrical and Electronic Engineering business Instrumentation |
| Zdroj: | tm - Technisches Messen. 84:502-511 |
| ISSN: | 2196-7113 0171-8096 |
| DOI: | 10.1515/teme-2017-0012 |
| Popis: | In industry, manual visual inspection is typically applied to assess surface imperfections on basic optical elements according to the standard DIN ISO 14997. This article proposes a machine vision setup to mimic the human tester's inspection process. It consists of multiple cameras and LED light sources. Both are arranged on the surface of a hemisphere with the optical element to be inspected at its center. By enabling individual LED sources on the hemisphere, any movement during acquisition can be omitted. Thus, the system is capable of acquiring a sparse pseudo BRDF (Bidirectional Reflectance Distribution Function) representation of imperfections. It is shown by experiments that this representation allows to discriminate between certain imperfections. Besides the mechanical setup, the image processing methodology and classification results are discussed. A comparison to results from manual inspection for 20 optical elements of the same geometry is also presented. Results indicate that a good agreement with the de-facto standard manual inspection method from industry can be obtained by the system. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|