About

About
The variable parameters are geometrical parameters that can be selected in this table and that are modified during an optimization process in order to minimize a global merit function (defined in the about section of the merit functions table). The modified values then automatically replace the initial ones in the related input tables for further analysis calculations or further optimization of the optical system.

The variable parameters that can be selected correspond to the type of surfaces entered in the mandatory parameters table of the surface parameters input page.

Therefore, if some variable parameters are disabled and may be useful for optimization, the mandatory parameters table should first be modified. For instance, a surface should first be declared as "aspherical" in the type cell for enabling the related aspherical coefficients to be used as variable parameters. In the same way, "yes" should be selected in the tilts-decenter cell to allow the tilts and decenters to be used as variable parameters.

Note that the radius of curvature R of the first surface is selected by default but it may not be relevant depending on the optical system and the optimization to be processed.