Virus microscopy – or perhaps more proper, ‘nanoscopy’, since their typical dimensions are on the nanometer scale – is crucially important for their identification and study. The required high spatial resolution can be achieved by transmission electron microscopy (TEM), but at the expense of using high-energy (typically 50 – 400 keV) electrons that cause substantial radiation damage. A less invasive variant of virus electron microscopy would be highly desirable. Here, we present the first low-energy electron microscope (LEEM) observation of viruses. SrRuO₃ films and Nb-doped SrTiO₃ bulk single crystals are introduced as excellent new substrates for LEEM studies. High-quality images of the tobacco mosaic virus (TMV) are obtained with electrons at just a few eV, or even without reaching the surface. LEEM offers easy sample preparation, tens of high-resolution images per second, and no radiation damage. With additional capabilities such as spectroscopy and diffraction, it is a promising technique for the study of viruses and other biological nano-objects.

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