The Design And Study On Multi-channel Fiber Optical Rotary Joint

With the rapid development of the information technology, how to improve the digital signal communication between rotating devices has become a vital role in the process of data transmission. Due to the excellent performance, Fiber Optical Rotary Joint (FORJ) as the device to achieve that function has been widely used in various fields. This thesis systematically described the development of FORJs, and summarized the advantages and disadvantages of existing designs. According to the functional qualities of the multi-channel FORJ, and the principles of geometrical optics, a new dual-channel FORJ was designed, with the optical system fully analyzed. On the basis of the operating principles of Dove prisms, the existent influencing factors of the multi-channel FORJ based on Dove prism were analyzed, so as to guide the design and adjustment of the multi-channel FORJ.The major achievements in this thesis are as follows:1,The operating principle of C-lens fiber collimator was analyzed, then the key technologies which can be utilized to manufacture fiber collimators of excellent performance were proposed. The extra coupling loss caused by assembly misalignments while two fiber collimators align and couple was investigated, and the calculation formulas were derived.2,A dual-channel FORJ using optical system was designed, the optical configuration was theoretically analyzed with the help of tangent method, and simulated in the FRED optical software; according to the above results,each component of the system was selected and designed. An experiment platform was built to adjust the designed FORJ, and then the system structure was optimized. At last the insertion loss, rotating variation and return loss of the adjusted FORJ were tested.3,Using the method of geometrical optics, the influence of manufacturing errors and assembly misalignments of Dove prism on deflection of output light and coupling loss were researched in theory. In order to verify the validity of the theory, the two kinds of errors were simulated by using FRED software, then a test system was built and the experimental analysis was carried out.4,A design scheme of multi-channel FORJ was proposed, and through the theoretical analysis and practical considerations,the clamping adjustment device and I/O end cover for collimating were designed. Then the insertion loss, rotating variation and return loss of the assembly multi-channel FORJ were tested.