Paraxial analysis of mechanically compensated zoom lenses 1: Four-component type

This paper presents a paraxial study of the various types of four-component mechanically compensated zoom lens in terms of Gaussian Brackets. The expressions which define the displacement of components at zooming, the extremum of displacement, and the singular point of displacement are derived. As a result of the study, a new classification of four-component mechanically compensated zoom lenses is given. Some numerical examples of the zooming locus are shown.