Polyfocal display
Polyfocal display is an interactive technique that allows to selectively zoom in a section of an image. Scaling is described by a (two–dimensional) magnification function, providing for generating several foci — each having induvidual magnification–parameters and correspondingly adjustable distortion in the regions further away from the focus.
Polyfocal display was proposed by Naftali Kadmon and Eli Shlomi for presentation of statistical data on cartographic maps.