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Department of Engineering, ICT and Technologies for Energy and Transport Patent Title Improvements in the optical interconnection systems between signal switching circuit boards. Ref. CNR 10276 Assignee(s): CNR CNR Institute: ITIA Main Inventor: Vito Basile Countries: EP, US Priority date: 26/06/2013 Abstract The present invention refers to an optical interconnection circuit for backplane in high capacity ICT apparatus and related automatic assembly method. The solution is based on a planar (on the backplane or on a close parallel plane) development of the fiber optics ribbon paths inside a mechanical support (frame) and a controlled deformation of the optical fibers thanks to mechanical constrains embedded into the frame. The optical fibers ribbons are general purpose and available and all connectors are standardized. The overall optical interconnection circuits are partialized into N independent circuits, each of which connects all cards mounted on the backplane. This partition has considerable advantages in terms of ease of maintenance (time and cost reduction). In the Tx-Rx connection, optical fibers are not splitted and they always remains inside a ribbon. Background The state of the art consists of external optical circuits. These circuits are made in two types: Flexible circuits (optical fibers are placed on a flexible substrate) or Stiff circuits (optical fibers are assembled inside a stiff housing). In all cases, starting from Tx connectors, all optical fibers of each ribbon must be splitted and routed to the Rx connectors. Each backplane optical circuit is a monolithic object. Technology The solution is based on controlled deformations of the optical fiber ribbons, using an optimized layout and special components as fibers support and protection (frame). These frames have been designed with constrains (pins, boundary walls, etc) that enforce the ribbons to take an optimized position. Fully automatized assembly technologies, based on automatic vision systems, robotics, industrial automation, are used for the circuit assembly. Advantages and Applications The invention finds application on high capacity ICT apparatus and big data center apparatus for internet. Moreover the assembly method can be applied to other sectors. Advantages: size reduction compared to the state of the art; more effective production process; modular backplanes; more efficient and cheaper system maintenance; use of commercial optical fibers; IP protection. Development stage The optical interconnection circuit development and prototyping have been completed. The prototypes have successfully passed all optical and functional tests. Optical circuits production, manufacturing technologies and related costs have been evaluated. A robotic assembly cell has been developed for a full automated optical circuits production. The solution is ready for large scale manufacturing. 89