Error analysis and coating thickness control method for the narrow band DWDM filter

To improve the productivity of fabrication of the narrow band DWDM film filter,the monitoring method and error in coating this film is discussed.Monte Carlo method is used to model the tolerance of the layer for the filter,and the results are used to select the easy coating film system.The film thickness error of each layer is obtained by calculating the Macleod maximum sensitivity.The compensation of the film thickness between each layer is obtained by modeling the optical monitoring processes and the film admittance.The strategy of controlling the film thickness is obtained through the above measures,and the experiments have proved that this is crucial to coating the film for the filter and impoving the productivity.