OPTICAL BACKPLANE WITH FREE-SPACE OPTICAL INTERCONNECTIONS USING TUNABLE BEAM DEFLECTORS AND A MIRROR FOR BOOKSHELF-ASSEMBLED TERABIT PER 2ND CLASS ASYNCHRONOUS TRANSFER MODE SWITCH

We have designed an optical backplane with free-space optical intercon nections using tunable beam deflector arrays and a mirror for terabit per second class bookshelf-assembled asynchronous transfer mode (ATM) switches. Optical beam transmitter arrays and optical beam receiver ar rays are placed on the edges of a printed circuit board. Optical beams are deflected individually by the tunable deflector arrays, emitted o bliquely and downward, and reflected at the mirror placed on the backp lane, passing through some printed circuit boards, and reach the targe ted receivers on the edges of printed circuit board. As a preliminary experiment, we show that board-to-board free-space arbitrary optical i nterconnections are possible using a tunable beam deflector array and l-mm-pitch 2x2 optical beam array provided with a vertical cavity surf ace emitting laser diode, we also show that these optical interconnect ions are made very stable by attaching reinforcing frames to the print ed circuit board. Furthermore, we show that more than 1000 channel int erconnections per printed circuit board are possible using a I-mm-pitc h optical beam array. As the speed per channel may be more than 1 Gbit /s, the throughput of the interconnection per board reaches almost the terabit/s level. Using this optical interconnection system is used, A TM switches with a huge capacity of 1.0 to 10 Tbit/s will be possible. (C) 1998 Society of Photo-Optical Instrumentation Engineers.