Abstract

The optical characteristic of multilayer optical coating is pertinent to the layer refractive indices, thickness and the number of the layers. However, in many cases the merit function of optimization techniques such as Damped-Least-Squaves, Gradient or Variable Metric only deal with the two former, not include the last. So the result is that virtually all optimization techniques are subject to convergence at local minimum and therefore search for the global minimum or even “a locally optimization minimum” is a formidable problem. A very powerful new optical film design technique, called the needle optimization whose merit function includes the three said factor, has been developed to solve problem of the design by Tikhouravov. During mathematical optimization process, the new layer is automatically inserted into the existing multilayer until the design goal are met or the insertion of a new layer effects further improvement.

© 1998 Optical Society of America