title: Estimation of visibility of phase contrast with extraction voltages for field emission gun electron microscopes.
abstract: Estimation was made for visibility of phase contrast with varying extraction voltages. The resulting decay rates of visibility show that images with low image contrast from cryo EM will be seriously impacted with high extraction voltages.
authors.affiliation: WsystemSolution, P.O.Box 3300 Latham, 12110-9998 NY, United States. Electronic address: xmeng101@gmail.com.
authors.forename: Xing
authors.initials: X
authors.lastname: Meng
keywords: Cryo em; Electron microscopy; Phase contrast