Optical links offer many advantages over copper based solutions for 10 Gb/s interconnects, including lighter
weight, longer reach and lower power consumption. Copper solutions are either very bulky and of limited
reach (10GBASE-CX4) or have high power dissipation (>10W for a 10GBASE-T link). Previous optical
solutions for high-volume, short interconnects have been limited by cost and connector cleanliness
considerations. In this paper, we describe a duplex active optical cable which overcomes these limitations.
Active optical cables not only retain the advantages of optical links with the external characteristics of an
electrical cable, but provide additional advantages in performance and yield by eliminating the extra link
margins inherent in open optical link standards.
A new electrical connector is described which provides excellent return loss performance, high density and a
rugged, consumer friendly design. Performance results for 15m graded index plastic optical fiber and 100m
multimode glass fiber based cables are reported. Low jitter contribution and power dissipation of ~1W per
link are achieved. Finally the design and performance of adapters allowing the use of this cable in present
SFP+ and XFP transceiver systems is presented.
A new optical switch design is reported consisting of two sets of parallel channel waveguides
intersecting at right angles. Arrays based on Ti:LiNbO3 technology, with waveguide intersections iron
doped to provide photorefractive sensitivity, have been fabricated. Interfering guided beams are used to
write index gratings at the waveguide intersections, which in turn diffract a portion of an incident signal
beam into the crossing waveguide. Arrays ranging from 15 x 15 up to 50 x 50 waveguides are
constructed in an active area of 5 mm square. Diffraction efficiency and writing time measurements are
reported along with a brief theoretical analysis. A proposal for a practical architecture offering
nondestructive readout is described.