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Thin Film Center Inc. 2745 E Via Rotonda, Tucson, AZ 85716-5227, USA Telephone: +1 520 322 6171 Fax: +1 520 325 8721 Email: info@thinfilmcenter.com |
Simulator Enhancement
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Tolerance assessment in optical coating production is a real problem. There is no good, universal, analytical technique. Errors, a simple tool in the Essential Macleod, assumes independent random thickness errors in all layers and can quickly show that independent control demands impossible accuracies in many coatings that can actually be constructed using other methods. In fact, tolerances and effects of errors depend strongly on the control technique. Simulator solves the the tolerancing problem by extending the Monte Carlo approach of Errors into a realistic model of the control process. Using a control plan created by Runsheet, Simulator models the control of deposition, introducing both random and systematic effects such as noise on the signal, tooling factor variation, packing density errors, and so on, and shows the effect that these parameters have on the final simulated production coatings. Simulator answers much more than simple monitoring questions. All kinds of other parameters associated with the coating system can be translated into the parameters of the model and their effect examined. Simulator results show how a simple change to the procedure for the monitoring of certain critical layers with no changes in the system noise or accuracy can lead to a substantial improvement in the predicted yield of multiple cavity beamsplitters for DWDM applications.
Note that for Simulator to operate correctly the Runsheet enhancement must also be present. |
For more information please contact Thin Film
Center.