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[OIC 2004
Design Contest]

 

 

 

Global Optimization Design Technique
   

Overview

This home made-program uses a global optimization procedure developed by T. Csendes et Al. in respiratory system modelling.

The multi-dimensional space composed of the different parameters (thickness) is divided into clusters formed by single linkage method.
The distance between a set of initial parameters X0 and the parameters X10 corresponding to the local minimum found is evaluated. A new point X1 will join the (X0; X10) cluster if there is a point in the cluster with which the distance is less than a critical distance calculated automatically by the program. If the new point is not clustered, a new local minimum X11 is searched.
The process is repeated until the whole space, possibly reduced to a nominal interval is clustered. The local search procedure is an algorithm of Quasi-Newton type which uses the Davidon-Fletcher-Powell formula.
For more details, see
T. Csendes, B. Daroczy, Z. Hanos, “Nonlinear parameter estimation by global optimization: comparison of local search methods in respiratory system modelling”, System Modelling and Optimization, 188-192, Springer Verlag, Berlin, 1986


Results

Optical Interference Coatings 2004 (Tucson): 2nd place (Design Problem A) and winner of the Design Problem B. Click here for more information.

 

   

 

Needle optimization technique with Quasi-Newton algorithm:
Examples of Optical Coating Designs

 

   

Starting Design

One single high index layer.
The nominal thickness influences the number of layers of the final solution.

Data

Glass Refractive index ns = 1.52
Supertrate medium Air n = 1.
High index material: nh = 2.35
Low index material: nb = 1.45

Cross points: target
Diamond-shaped points: spectral response of the optimized coating

Normal Incidence


 

45 degree incidence

Light gray points: p-polarisation
Dark grey points: s-polarisation