Focusing in Automated Microscopes

Automated microscopy is being promoted by applications requiring long-time-lapse imaging, or fast image acquisition. These systems are very advantageous, but focusing on the specimen is still a fundamental problem. Defocusing might be caused by thermal instabilities, vibrations of the system and immersion media or microscope slide fluctuations. The problematic is being compensated passively, through thermalisation or isolation chambers, capacitive or reflective distance stabilization, co-localization comparison… and actively with contrast or edge detection, aperture correlation and correction-collar optics. These different autofocus-technologies will be compared for common commercial cell-culture containers. The results can be applied, for instance, to adequately gauge motorized collar-rings.