Optical wavelength separators using thin film coating on an absorbing substrate

An new wavelength separator device is presented. The device consists of a single layer coating material on an absorbing substrate. The new device will be used to separate wavelengths in optical networks. The proposed design approach is applied for two devices that operate in the UV and visible regions. The proposed devices can be used to separate two or four wavelengths. The continuous increase in using optical communication systems in diverse fields has stimulated the need for optical devices that improve system performance. Currently, wavelength separation, multiplexing and modulation schemes are the backbone of most communication systems and they will play a more important role in the next generation optical systems since they allow more bandwidth and increasing number of transmitted channels. Optical wavelength separator devices allow selecting signals having specific wavelength. A number of devices were reported in the literature that uses different approaches in wavelength division and separation. This work presents a new approach for designing a wavelength separator for optical applications. The design approach of the device is based on coating an absorbing substrate with a single thin film layer. The two case studies considered in this work operate in ultraviolet and visible ranges. These are useful for integrated optic circuits where the dimensions of the devices and the optical attenuation are highly reduced. The same design approach can be used for materials that are more convenient wavelengths used in optical fiber systems.