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PubMed · 10655557

Robust autofocusing in microscopy.

J M Geusebroek·F Cornelissen·A W Smeulders·H Geerts
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Abstract

BACKGROUND: A critical step in automatic microscopy is focusing. This report describes a robust and fast autofocus approach useful for a wide range of microscopic modalities and preparations. METHODS: The focus curve is measured over the complete focal range, reducing the chance that the best focus position is determined by dust or optical artifacts. Convolution with the derivative of a Gaussian smoothing function reduces the effect of noise on the focus curve. The influence of mechanical tolerance is accounted for. RESULTS: The method is shown to be robust in fluorescence, bright-field and phase contrast microscopy, in fixed and living cells, as well as in fixed tissue. The algorithm was able to focus accurately within 2 or 3 s, even under extremely noisy and low contrast imaging conditions. CONCLUSIONS: The proposed method is generally applicable in light microscopy, whenever the image information content is sufficient. The reliability of the autofocus method allows for unattended operation on a large scale.

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AnimalsAutomationCaenorhabditis elegansEvaluation Studies as TopicHumansMicroscopyMyocardiumNeuronsQuality ControlRatsJournal Article

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J M Geusebroek, F Cornelissen, A W Smeulders, H Geerts. 2000-01-01. Robust autofocusing in microscopy.. https://pubmed.ncbi.nlm.nih.gov/10655557/

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