Overcoming resolution-loss mechanisms in laser phase plate cryo-electron microscopy.

Abstract

Lack of image contrast is a central limitation in transmission electron microscopy (TEM) of vitrified biological samples (cryo-EM). A phase plate maximizes the image contrast by applying a spatially-selective phase shift to the electron beam in a diffraction plane of the microscope. Previously realized phase plate designs require a material object to be placed in the electron beam, which leads to image aberrations and resolution loss due to charging of the phase plate and/or scattering of the electron beam.