A New Automatic Focusing Algorithm and its Application on Vision Measuring Machine

Abstract:

The way to realize the automatic focusing rapidly and efficiently is a focus in some automatic optical inspection case. The key problem is how to select a suitable focusing evaluation function and design an effective auto-focusing algorithm. In this paper, based on comparing some well-known focusing evaluation functions, a new automatic focusing algorithm was presented. It used two steps to do the search. At the first step, it searched a large region quickly just to get the approximate focusing position, the next step was to do precise search in a small area in order to get the exact focusing position. This new algorithm performed well on the vision measuring machine and could focus rapidly and exactly.

• Periodical: Applied Mechanics and Materials (Volumes 397-400)
• Pages: 1523-1528
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.397-400.1523
• Online since: September 2013
• Authors: Hua Dong Zou, Hao Xiang Wang
• Keywords: Automatic Focusing, Delicacy, Deviations Function, Evaluation Function, Frequency-Spectrum Function, High-Pass Filter

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