Research And Experiment Of Fiber Optic Rotary Joint

In resent years, optical fiber technology has made extraordinary progress. More and more applications need to use fiber optic rotary joints (FORJs) to transmit signals. The development of FORJs is systematically described in this thesis. The advantages of multi-channel FORJs and single channel FORJs are discussed in detail. The significance of developing multi-pass FORJs is analyzed. And a multi-channel FORJ is designed using Dove prism. According to the image rotation theory of Dove prism, rotary coupling of multi-channel optical signals is realized using a gearing system with an angular speed ratio of 2:1.The major achievements in this thesis are:1. From a theoretical viewpoint, the relationship between ejecting light deflection angle from Dove prism and rotation axis deflection angle is analyzed under the condition that the angle of rotation axis of Dove prism and x coordinate axis is very tiny. The relationship between the rotation axis deflection angle and the additional loss due to angular misalignment is deduced.2. A four-channel FORJ based on Dove prism and fiber collimator is designed. A regulate structure is developed to adjust this multi-channel FORJ. The insertion loss due to mechanical misalignments and mechanical rotation in a single channel of this multi-channel FORJ are tested and analyzed in detail.3. The design and experiment of single-mode single-channel FORJ are achieved. The insertion loss induced by mechanical misalignments and mechanical rotation are tested and analyzed.4. In order to test the capability of dynamic signal transmission of FORJ. A rotation testing platform is designed which is used for the FORJ to transmit signals through relatively rotary surfaces.5. The environmental test of the single-mode single-channel FORJ is accomplished, including temperature test, vibration test and impact test. The reliability of the single-channel FORJ is verified.