The Dublin Lens: A Cc=1.0 mm Objective Lens Intended for CryoEM at 100 keV

Germano Motta Alves; Theo Andrews; Patrick McBean; Torquil Wells; Mohamed M. El-Gomati; Stephan Burkhalter; Clemens Schulze-Briese; Pietro Zambon; Greg McMullan; Richard Henderson; Christopher J. Russo; Lewys Jones

arXiv · 2505.11458

The Dublin Lens: A Cc=1.0 mm Objective Lens Intended for CryoEM at 100 keV

Germano Motta Alves·Theo Andrews·Patrick McBean·Torquil Wells·Mohamed M. El-Gomati·Stephan Burkhalter·Clemens Schulze-Briese·Pietro Zambon·Greg McMullan·Richard Henderson·Christopher J. Russo·Lewys Jones

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Abstract

We have designed, fabricated and tested a lens with chromatic aberration coefficient (Cc) of 1.0 mm, a 4.0 mm pole-gap and 2.0 mm bore that is wide enough to accommodate an anti-contamination system and an objective aperture. This lens extends the temporal-coherence envelope of the electron microscope beyond 2 Angstrom, using a low-cost Schottky FEG. We hope that this lens design can be used to improve all 100 keV electron microscopes designed for single-particle electron cryomicroscopy (cryoEM).

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Germano Motta Alves, Theo Andrews, Patrick McBean, Torquil Wells, Mohamed M. El-Gomati, Stephan Burkhalter, Clemens Schulze-Briese, Pietro Zambon, Greg McMullan, Richard Henderson, Christopher J. Russo, Lewys Jones. 2025-05-16. The Dublin Lens: A Cc=1.0 mm Objective Lens Intended for CryoEM at 100 keV. https://arxiv.org/abs/2505.11458

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