Method of determining Gaussian parameters for zoom systems with multiple moving lens groups

A new computable method of determining Gaussian parameters is presented for zoom systems with multiple moving lens groups. These lens groups are no longer divided as focus changing groups and compensating groups. Displacements and focal lengths of all the moving lens groups are taken as variables in optimization, and the Gaussian parameters are solved for all the focal positions simultaneously, with the F-number of each lens group constrained to a rational value. A test program is developed using the algorithm. The results of a design example show that the method is practical and is a step toward the intelligent computer-aided design of zoom systems.