Development Of A 4×4 Waveguide Optical Switch Device

With the development of all-optical network,optical cross-connect is more and more important.As its core devices,the optical switches and arrays are the hot topics of extensive research.In this thesis,a low-cost,large-scale integrated optical switch array device based on magnetic fluid drive is developed.This thesis focuses on the following four aspects:1.The status of optical switches is investigated firstly and all kinds of key technologies are outlined.Comparing the performance of all kinds of optical switches,an optical switch device structure based on electromagnetic driving is proposed.The structure of the device is divided into four layers,from the bottom to the upper is a bottom cover with a reservoir function,a magnetic fluid driven core with an array of through-holes,an inner core of a slab waveguide and an upper cover with holes.A triangular through hole is arranged at the waveguide cross node of the inner core of the slab waveguide,the through hole in the inner core is driven by the magnetic fluid,and the hole array of the upper cover corresponds to each one.Due to the hierarchical structure of the device,each layer can be independently produced and experimentally verified,which makes it easy to process and ensures high yields.Its basic working principle is to control the movement of the matching liquid column above the magnetic fluid by using the current magnetic effect,so as to achieve the filling of the refractive index matching liquid at the through hole of the waveguide node and achieve the function of "on" and "off" of the optical path.2.The structure of the magneto-optic drive unit of the optical switch node is designed and experimentally verified.The shape,number of turns and magnetic field distribution of the control coil are calculated,analyzed and optimized.The structure of the MHD unit has been optimized and its working parameters such as response time,insertion loss and working current have been fully researched,and the experimental model has been made.The experimental verification has been done.Theoretical analysis and experiments show that when the structure of this structure is set to drive liquid column 30 ?m,the driving current is less than 1.5A.Finally,magnetic fluid is prepared by the method of chemical precipitation.3.An optical waveguide array and node model suitable for the optical switch is designed,3D numerical simulation software lumerical is used to get the appropriate node shape,insertion loss and crosstalk.The optimized structure of a single node insertion loss is less than 0.2dB and return loss is more than 49 dB.4.The 4 × 4 optical switch array model is completed and the related performance test is carried out.The experiment shows that the response time of the optical switch is about 20 ms,the insertion loss is about 3.1dB and the return loss is about 45 dB.