Design And Fabricating Of Bend Multimode Optical Waveguide In Class Substrate

With the rapid development of mobile Internet, cloud computing and other business, people require communication network has more and more data transmission bandwidth. The traditional electrical interconnection based on the copper wire technology is facing a series of problems, such as:crosstalk, power consumption, skin effect, etc. Making the bandwidth of the electrical interconnection data is difficult to meet the needs of modern communication network data transmission bandwidth. Optical interconnection technology has a series of advantages, such as:no crosstalk, low dissipation, large bandwidth, resistance to electromagnetic interference, low cost, etc, providing a new way to solve bandwidth bottlenecks of the electrical interconnection in the data transmission. At present, electro-optic printed circuit board (EOPCB) become the research emphasis in the next few years. Among them, the coupling problem between the optical interconnection layer and optical transceiver module level has become a problem which hindering the development of EOPCB.In this paper, a kind of90°bend multimode optical waveguide structure is proposed and is studied in experimental and theoretical aspects. First of all, compared two calculation methods of multimode optical waveguide bending loss:wave optics and geometrical optics. Finally, The bending multimode optical waveguide model was built by Tracepro software and calculating the bend loss by ray tracing simulation. The relation between the transmittance with light source divergence angle, width of the waveguide core, the bending radius and numerical aperture of the waveguide is studied and using transmittance characterized the multimode optical waveguide bending loss.Finally,the optimal parameters of the bend multimode optical waveguide is given. Which make bending radius within5mm-7mm waveguide core width of50um bend waveguide, select divergence Angle within7°light source as the input light bending optical waveguide.This paper has reported the fabrication of bend multimode optical waveguide through thermal Ag+-Na+ion-exchange and field-assisted ion-diffusion technology. Microscopic structure picture of bend multimode optical waveguide was observed by optical microscope and test the propagation loss of optical waveguide. The test result show that the average of waveguide depth is42.765μm, core dimension of multimode bend optical waveguide being51.17μm×26.93μm. The light spot is bright and tend to round shape. The tested results show that the propagation loss of bend multimode optical waveguide with core width50μm arrived the minimum value at bending radius of7.5mm.The minimum value is respectively2.27dB/cm. Experimental value is consistent with the simulation values, which also suggests that multimode90°bend optical waveguide has the possibility that applied to EOPCB.The results indicate that multimode90°bend optical waveguide can be used for low loss, low cost, convenient vertical coupler which has great application prospects in the field of optical interconnection and has important significance to improve coupling efficiency of EOPCB.