Application of thin film errors sensitivity control concept to robust design of multilayer optical coatings

A robust design method of multilayer optical coatings based on optimal control of thin-film errors sensitivity is presented in this paper. An analytical calculation model of robust design merit function under statistic layer parameters errors is established. It can avoid the computation errors of robust design merit function caused by limited number of layer parameters errors simulation sample,and can avoid the long time consumption when large number of layer parameters errors simulation samples is used. The effectiveness of the robust design method in thin film errors tolerance control is demonstrated by application to a variety of optical coatings,such as the broadband antireflection coating,neutral beam splitter and linear ramp transmittance filter. Results show that the robust design method owns an inherent fast computation characteristic and the designed film is insensitive to the monitoring thickness errors in deposition process. This method is of practical significance to improving the mass production yields and repetitive production of high quality optical coatings.