The change in focus of a high-resolution electron microscope is generally assumed to be linear with change in objective lens current. Thus the defocus step size should be constant for a constant step in lens current. Measurements on the LBNL One-Angstrom Microscope show that the step size increases with increasing underfocus (reduced lens current). Differentiation of the best-fit quadratic shows that the defocus step size varies linearly as defocus changes.
O'Keefe, Michael A., and Nelson, E. Chris. Defocus step size of the LBNL One Angstrom Microscope. United States: N. p., 2002.
Web. doi:10.2172/817235.
O'Keefe, Michael A., & Nelson, E. Chris. Defocus step size of the LBNL One Angstrom Microscope. United States. doi:10.2172/817235.
O'Keefe, Michael A., and Nelson, E. Chris. Tue .
"Defocus step size of the LBNL One Angstrom Microscope". United States.
doi:10.2172/817235. https://www.osti.gov/servlets/purl/817235.
@article{osti_817235,
title = {Defocus step size of the LBNL One Angstrom Microscope},
author = {O'Keefe, Michael A. and Nelson, E. Chris},
abstractNote = {The change in focus of a high-resolution electron microscope is generally assumed to be linear with change in objective lens current. Thus the defocus step size should be constant for a constant step in lens current. Measurements on the LBNL One-Angstrom Microscope show that the step size increases with increasing underfocus (reduced lens current). Differentiation of the best-fit quadratic shows that the defocus step size varies linearly as defocus changes.},
doi = {10.2172/817235},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Tue Jul 02 00:00:00 EDT 2002},
month = {Tue Jul 02 00:00:00 EDT 2002}
}