Exit Wave Restoration

Only image intensities can be recorded in an electron microscope and therefore the phase of the electron wave, which provides much of the important structural information, is lost. The high resolution images also suffers from aberrations introduced by the objective lens, and from electrical and mechanical instabilities of the microscope, which ultimately limit the resolution of the data.

To overcome these problems, we are developing indirect restoration methods which recover the electron wave at the exit plane of the specimen (and hence the phase information) and which fully compensate the microscope aberrations. These restored exit wave functions are recovered from a series of images in which either the defocus or the incident beam direction is altered for each member.