Note the currently defined merit function is used, and all parameters that are variable are re-optimized during this process. The current merit function should be appropriate for an aspheric design, which may require higher sampling than a non-aspheric design for good optimization. In addition, thickness controls other than just center and edge thickness may be required. The “full thickness” boundary constraint operands FTGT (Full Thickness Greater Than) and FTLT (Full Thickness Less Than) are useful for bounding aspheres: see this Knowledge Base article and the User's Guide Optimization chapter for more details.

Note also that like all local optimization results, there is no way to know if the solution found is the optimum "global minimum" for that combination of merit function, variables, and design parameters. For this reason, once the best candidate asphere is determined, it is usually a good idea to run the Hammer Optimizer on the resulting design to see if any further gains are possible.

No attempt is made to determine whether the resulting asphere is practical to fabricate, or is more or less costly to manufacture as compared to making other surfaces aspheric.