Research Of Active Optical Rotary Joint

Optical rotary interconnection is a multi-discipline technique, which combinesthe study of optical transmission, circuitry and precise mechanical design. And itallows transmission of optical signals through rotating interfaces to stationaryapparatus. It is indispensable in the fields of military and civil applications, wheredynamic transmissions of optical signals, immune to electro-magnetic interference(EMI) and small size are required. But common optical rotary joints havedisadvantages of extremely high-precision mechanical assembly requirements,complex configuration and high cost. In this paper, to avoid these shortcomings, twoschemes of ORJ are presented: infrared spatial interconnection rotary joint andopto-electronic hybrid fiber-optic rotary joint using quarter-pitch graded-index (GRIN)rod lens. These two optical rotary joints have such advantages as simple mechanicalconfiguration and easy realization of optical coupling. The research on the systemdesign and optimization is helpful to the application of existent techniques and thedevelopment of novel optical rotary joints. Major work of this thesis: 1. The scheme that applies the wireless infrared communication technique tothe design of optical rotary joint was presented. Based on the analysis of the designrequirements for both rotary joint and wireless infrared communications, the systemarchitecture of infrared spatial interconnection rotary joint was designed. 2. The circuit of the infrared spatial interconnection rotary joint was designed.The implementation of the electronic circuit was discussed in three aspects, i.e.,computer interface, communication control, infrared transmitting and receiving. Thesimulation of the transmitting and receiving procedures was also finished. Thehardware circuit was designed with new modules to achieve improved function andsmall size. 3. The adaptability of the infrared spatial interconnection rotary joint wasverified through experiments. The transmission performance in different operatingsystems (OSs) was analyzed and evaluated. The data rate and transmission stability IIIwere also tested. Moreover, conclusions about transmission characteristics weredrawn. 4. The infrared data link in the rotary joint was optimized. Based on the analysisof the characteristics of the wireless infrared channel regulated by IrDA protocol, acollimation optical system was designed to optimize the optical link of the infraredspatial interconnection rotary joint. With this optical system, the radiation angle canbe reduced and the transmission performance of the rotary joint can be improved. 5. The opto-electronic hybrid fiber-optic rotary joint using GRIN was designed,in which the configurations of active and passive optical rotary joints were combined.The GRIN lens was used to collimate the light in the rotary part. And theopto-electronic and electro-optic conversion circuits were allowed to receive theoptical signal. The two parts accomplished the signal connection. In the paper, boththe architecture and the each of implementation part were designed according to thesystem requirements. In addition, the optic coupling efficiency was calculated toevaluate the validity of the opto-electronic hybrid fiber-optic rotary joint. Major innovation of this thesis: 1. The wireless infrared communication technique was applied to design theoptical rotary joint and realize the optical dynamic transmission in the infrared spatialinterconnection rotary joint. 2. A method to optimize the infrared link was presented. As a core of themethod, an integrate collimate optical system was designed to optimize the infraredlink and improve the transmission quality of infrared channel in the infrared spatialinterconnection rotary joint. 3. The opto-electronic hybrid fiber-optic rotary joint was designed, whichcombined the configurations of active and passive optical rotary joints. In t...