Data transmission between rotating and stationary systems, e.g. required for radar antennas or for undersea cable installation ships can be realized with so called rotary joints. For the transmission of several high bit rate optical data channels a micro optical rotary joint is now available which guarantees a dead reliable, low loss transmission for up to 21 parallel single mode channels. The free space transmission in the rotary joint implicates a highly precise collimation of the parallel channels. For this purpose compact two dimensional fiber collimator arrays based on micro lens arrays have been developed. These arrays and the complete opto-mechanical system are designed with the help of tolerance analysis using Monte Carlo simulations. Besides these results also some more information on the behavior and the characteristics of the micro optical rotary joint under real conditions which demonstrate the excellent characteristics of this novel system will be given.
In optical communication there are systems requiring a parallel transmission of several high bit rate data channels based on singlemode fibers. Especially for a free space transmission within such a system a precise collimation of the parallel channels is necessary to guarantee a low loss system. For this purpose compact two dimensional fiber collimator arrays can be used. A main quality characteristic for this arrays is the pointing accuracy, the angular deviation of the collimated beams to a theoretical optical axis. The angular deviation is caused by a lateral offset of the fiber axes to the axes of the corresponding micro lens. To minimize this offset we developed and analyzed an actor geometry for a fiber array which allows a laser based micro alignment of the fibers to the micro lenses. An alignment accuracy within submicrons can be realized which guarantees a pointing accuracy below 0.01 degrees. In this paper we demonstrate some important results of the FEM based analyzes to show the influence of different laser parameters for optimizing the alignment procedure and to minimize alignment time. Experimental results confirm the actor behavior calculated in the FE analyzes and demonstrate the qualification of laser based micro alignment of fibers for the assembly of highly precise two dimensional fiber collimator arrays.