Byoung-Ho Rhee

PCB-compatible optical interconnection using 45/spl deg/-ended connection rods and via-holed waveguides

In this paper, a new architecture for a chip-to-chip optical interconnection system is demonstrated that can be applied in a waveguide-embedded optical printed circuit board (PCB). The experiment used 45/spl deg/-ended optical connection rods as a medium to guide light paths perpendicularly between vertical-cavity surface-emitting lasers (VCSELs), or photodiodes (PDs) and a waveguide. A polymer film of multimode waveguides with cores of 100/spl times/65 /spl mu/m was sandwiched between conventional PCBs. Via holes were made with a diameter of about 140 /spl mu/m by CO/sub 2/-laser drilling through the PCB and the waveguide. Optical connection rods were made of a multimode silica fiber ribbon segment with a core diameter of 62.5 and 100 /spl mu/m. One end of the fiber segment was cut 45/spl deg/ and the other end 90/spl deg/ by a mechanical polishing method. These fiber rods were inserted into the via holes formed in the PCB, adjusting the insertion depth to locate the 45/spl deg/ end of rods near the waveguide cores. From this interconnection system, a total coupling efficiency of about -8 dB was achieved between VCSELs and PDs through connection rods and a 2.5 Gb/s /spl times/ 12-ch data link demonstrated through waveguides with a channel pitch of 250 /spl mu/m in the optical PCB.

Optical backplane system using waveguide-embedded PCBs and optical slots

As discussed in this paper, a practical optical backplane system was demonstrated, using a waveguide-embedded optical backplane board, processing boards, and optical slots for board-to-board interconnection. A metal optical bench was used as a packaging die for the optical devices and the integrated circuit chips in both the transmitter and the receiver processing boards. The polymer waveguide was produced by means of a hot-embossing technique and was then embedded following a conventional lamination processes. The average propagation loss of these waveguides was approximately 0.1 dB/cm at 850 nm. The dimension and optical properties of the waveguide in an optical backplane board were unchanged after lamination. As connection components between transmitter/receiver processing boards and an optical backplane board, optical slots were used for easy and repeatable insertion and extraction of the boards with a micrometer-scale precision. A 1/spl times/4 850-nm vertical-cavity surface-emitting laser array was used with 2 dBm of output power for the transmitter and a p-i-n photodiode array for the receiver. This paper successfully demonstrates 8 Gb/s of data transmission between the transmitter processing board and the optical backplane board.

Optical interconnection using fiber-embedded boards and connection blocks fabricated by a micro-grooving technique for fiber insertion

We fabricated fiber-embedded boards using a micro-grooving technique for optical interconnects. This approach is quite cost effective and fully compatible with conventional PCB processes. U-shaped grooves were formed on FR-4 plates using a 90? V-shaped diamond blade. Polyimide-coated glass fibers were inserted in the grooves followed by a conventional lamination process. The 12 fibers embedded in the board showed a good uniformity in their position with a fluctuation below ?8 ?m. Optical connection blocks were also fabricated using fiber segments embedded in a grooved silicon wafer piece in order to couple the light between a transmitter/receiver module and a fiber-embedded board. 45? mirrors were formed at the end of the connection blocks by mechanical polishing. An optical link of 2.5 Gb s?1 signals with a high coupling efficiency was demonstrated through the fiber-embedded connection blocks and a board.

Demonstration of 2.5Gb/s optical interconnection using 45/spl deg/-ended connection blocks in fiber- and waveguide-embedded PCBs

A simple method for fabricating fiber- and waveguide-embedded boards for optical interconnects is described. It is quite cost effective and fully compatible with conventional PCB processes. On-board optical link of 2.5Gb/s signals between the transmitter and the receiver modules. was demonstrated by placing connecting blocks having 45/spl deg/-mirror planes at the ends of the fiber and waveguide-embedded boards.

Pluggable Optical Board Interconnection System With Flexible Polymeric Waveguides

Pluggable optical board interconnection system using flexible optical waveguide for direct-coupling to reduce the transmission loss is proposed and demonstrated. For the direct coupling between waveguides of boards, we use optical plug and adaptor with flexible polymeric waveguide and guide pins. Flexible polymeric optical waveguide is fabricated using hot embossing technique. Eye pattern and jitter characteristics of the backplane system is presented at 10 Gb/s.

On-board optical interconnection of 2.5Gb/s x 12 channels data using fiber-embedded PCB

A simple method for fabricating fiber-embedded boards using a grooving technique for optical interconnects is described. It is quite cost effective and fully compatible with conventional PCB processes. On-board optical link of 2.5Gb/s signals between the transmitter and the receiver modules was demonstrated by placing connecting blocks having 45°-mirror planes at the ends of the fiber-embedded boards.