Ion sources for mass spectrometry

Provided are ion sources, methods of forming ions and mass analyzer systems. In various embodiments, the present teachings provide ion sources, methods for focusing ions from an ion source, and methods for operating a time-of-flight mass analyzer. In various embodiments, the present teachings relate to matrix-assisted laser desorption/ionization (MALDI) ion sources and methods of MALDI ion source operation, for use with mass analyzers. In various aspects, provided are ion sources and methods of operation thereof that facilitate increasing one or more of sensitivity and resolution of a TOF mass analyzer configured for multiple modes of operation.