JEOL is the only electron microscope supplier to offer commercially-available thin film phase plate technology to its Life Sciences customers, in particular those involved in cryo-electron microscopy and cryo-electron tomography. The phase contrast imaging capability of a phase-plate outfitted JEOL TEM increases specimen contrast by several factors.
While phase plate technology - invented by Frits Zernike and awarded the Physic Nobel prize in 1953 - is an accepted tool for live-cell imaging with the light microscope (LM), it is a novel approach to imaging with the TEM. However, completely analogous to the LM application, the application in the TEM employs a -phase plate that shifts the phase of only the scattered electrons, resulting in amplitude contrast rather than phase contrast, as these phase-shifted electrons interfere with the unscattered electrons in the image plane (See Fig. 1).
Extensive research has led to the extensive and rigorous development of the phase plate technology at the laboratory of Prof. Kuniaki Nagayama, Director & Professor of the Okazaki Institute for Integrative Bioscience in Japan. Prof. Nagayama and his colleagues have illustrated very convincingly the potential for routine phase contrast TEM imaging of frozen-hydrated macromolecules (See Fig. 2).
Furthermore, using custom software they have applied the phase plate imaging successfully to cryo-tomography.
JEOL’s TEM columns are optimally designed for phase contrast cryo-electron tomography, as they are unsurpassed in the ability to customize the imaging parameters without sacrificing ease of use. Also, the unique system’s architecture of the JEOL TEMs guarantees the ultimate in overall stability, which ultimately results in higher performance of the TEM. Furthermore, developments have led to continuously heated phase plate holders that come assembled with piezo drives and accompanying software for exact positioning of the phase plate in the back-focal plane of the objective lens, and zero loss energy filtering using the in-column Omega filter of the 2200FS.
For more information:
Phase Contrast Enhancement with Phase Plates in Biological Electron Microscopy, Nagayama et al., Microscopy Today (Vol 18, No 4), July 2010.
The Ultimate in Contrast – JEM-2200FS with Phase Plate
National Institute for Nanotechnology - A New Take on the Phase Plate