ISO/TR 19319:2013 describes: functions and their relevance to lateral resolution: point spread function (PSF), line spread function (LSF), edge spread function (ESF), modulation transfer function (MTF) and contrast transfer function (CTF); experimental methods for the determination of lateral resolution and parameters related to lateral resolution: imaging of a narrow stripe, sharp edge and square-wave gratings; physical factors affecting lateral resolution, analysis area and sample area viewed by the analyser in Auger electron spectroscopy and X-ray photoelectron spectroscopy.