New technologies will always lead to increasing demands and complexity of the layer stacks. High quality thin film optical filters need high precision optical monitoring during the deposition. There are many challenges to overcome to enable greater accuracy in optical thin-film coatings. Real time optimization during production can increase repeatability and yield for even the most complex optical layers. Intelligent optical monitoring integrates control technology, a strategy generator and the coater to offer seamless development of new optical film processes in shorter times and at lower cost by direct continuous monitoring.